PI: PETRIE, HOWARD T. Title: Lymphoid signals for stromal growth and organization in the thymus.

Received: 10/18/2010 FOA: PA10-069 Council: 05/2011

Competition ID: ADOBE-FORMS-B FOA Title: NIH Exploratory Developmental Research Grant Program (Parent R21)

1 R21 AI095831-01 Dual: HD,HL Accession Number: 3339225

IPF: 10005569 Organization: SCRIPPS FLORIDA

Former Number: Department: Cancer Biology

IRG/SRG: CMIB AIDS: N Expedited: N

Subtotal Direct Costs Animals: Y New Investigator: N

(excludes consortium F&A) Humans: N Early Stage Investigator: N

Year 1: Clinical Trial: N

Year 2: Current HS Code: 10

HESC: N

Senior/Key Personnel: Organization: Role Category:

Howard Petrie The Scripps Research Institute - Florida PD/PI 

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10/18/2010

The Scripps Research Institute

10550 North Torrey Pines Road

La Jolla

92037-1000

Kaye I.

Wynne

Lymphoid signals for stromal growth and organization in the thymus. 

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Petrie 

Howard T. 

33458-5284

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Jupiter

130 Scripps Way

Cancer Biology 

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Table Of Contents Page Numbers

SF 424 R&R Face Page------------------------------------------------------------------------------------------ 1

Table of Contents--------------------------------------------------------------------------------------------- 3

Performance Sites--------------------------------------------------------------------------------------------- 4

Research & Related Other Project Information------------------------------------------------------------------ 5

 Project Summary/Abstract (Description)---------------------------------------- 6

 Public Health Relevance Statement (Narrative attachment)---------------------------------------- 7

 Facilities & Other Resources---------------------------------------- 8

 Equipment---------------------------------------- 10

Research & Related Senior/Key Person-------------------------------------------------------------------------- 11

 Biographical Sketches for each listed Senior/Key Person---------------------------------------- 13

PHS 398 Specific Cover Page Supplement------------------------------------------------------------------------ 16

PHS 398 Specific Modular Budget------------------------------------------------------------------------------- 18

 Personnel Justification---------------------------------------- 21

PHS 398 Specific Research Plan-------------------------------------------------------------------------------- 22

 Specific Aims---------------------------------------- 23

 Research Strategy---------------------------------------- 24

 Vertebrate Animals---------------------------------------- 30

 Bibliography & References Cited---------------------------------------- 31

 Letters of Support---------------------------------------- 32

 Resource Sharing Plan---------------------------------------- 35

PHS 398 Checklist--------------------------------------------------------------------------------------------- 36

Table of Contents Page 3

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
County:

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The Scripps Research Institute - Florida

130 Scripps Way

Jupiter

FL: Florida

USA: UNITED STATES

33458-5284

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Performance Sites Page 4

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
1. * Are Human Subjects Involved?

IRB Approval Date:

Human Subject Assurance Number:

2. * Are Vertebrate Animals Used?

IACUC Approval Date:

Animal Welfare Assurance Number

4.b. If yes, please explain:

4.c. If this project has an actual or potential impact on the environment, has an exemption been authorized or an environmental assessment (EA) or 

 environmental impact statement (EIS) been performed?

4.d. If yes, please explain:

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7. * Project Summary/Abstract

11. Equipment

8. * Project Narrative

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6.a. If yes, identify countries:

1 2 3 4 5 6

9. Bibliography & References Cited

10. Facilities & Other Resources

Yes No

1.a If YES to Human Subjects

Yes No

Yes No

If yes, check appropriate exemption number.

Yes No

Yes No

Yes No

Yes No

Yes No

Yes No

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5.a. If yes, please explain:

	


 		

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Other Information Page 5

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PROJECT SUMMARY 

Like all blood cells, T lymphocytes are constantly lost during life, and must be continuously replaced. The 

thymus is the primary site of de novo T lymphopoiesis. Microenvironmental conditions unique to the thymus 

induce a complex series of developmental events in multipotent, marrow-derived progenitors, including positive 

and negative control of proliferation, T lineage specification, functional T lineage asymmetry, self-restriction, 

self-tolerance, and cell death/survival signals. Significant progress has been made in understanding the 

signals the thymus provides to lymphoid progenitors to induce and control these events. However, the 

proliferation, differentiation, and/or survival of the non-lymphoid (stromal) components of the thymus are 

equally dependent on lymphoid cells, and the absence of lymphoid cells (e.g., congenital immunodeficiency 

diseases) results in athymia, even though the nascent stromal cells are functionally competent. The signals 

that lymphoid cells provide to induce stromal growth, differentiation, and/or survival are completely unknown. 

In this proposal, we propose to address this process in a comprehensive fashion. Using our recently devised 

method for global characterization of stromal gene expression in situ, we will analyze the dynamic response of 

stromal cells to the presence of lymphoid progenitors in an inducible model of thymic growth. We will then 

identify stromally-expressed genes that encode receptors, and thus may respond to the presence of lymphoid 

cells, with particular emphasis on those that change during specific phases of the growth response (induction, 

log phase, termination, steady-state). We will verify the presence of the cognate ligands for these receptors in 

lymphoid cells, using informatic methods as well as manual means of curation. Cognate receptor:ligand pairs 

will then be prioritized using a variety of criteria, including dynamic patterns of expression, known functional 

relevance (growth, differentiation, survival) in other tissues, the availability of existing genetic models, etc. 

Finally, the biological relevance of a few high-priority candidates will be tested, using appropriate stromalreceptor or lymphoid-ligand mutant mouse models. This project is expected to provide novel insights into an 

unexplored area of biology that will not only fuel a better understanding of this process, but will facilitate the 

development of more mechanistic studies to characterize the unique, two-way interactions that occur between 

lymphoid progenitors and stromal cells in the thymus. 

Project Description Page 6

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PROJECT NARRATIVE 

The thymus is the primary organ where T lymphocytes are made, and thus is critical for normal 

immune function. Specialized cells inside the thymus (stromal cells) are responsible for instructing 

stem-like cells recruited from the bone marrow to undergo development into T lymphocytes. 

However, early in development, these stromal cells themselves require signals from immature 

lymphocytes to induce their own growth and development. In the absence of lymphocytes, for 

instance, as occurs in many pediatric immunodeficiency disorders, the thymus does not form. The 

goals of this project are to perform an in depth analysis of this very poorly understood two-way 

interplay between lymphocytes and stromal cells in the thymus, and how these processes shape the 

development of the immune system. 

Public Health Relevance Statement Page 7

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
FACILITIES AND RESOURCES 

Laboratory. The PI has ca. 3000 square feet of laboratory space at Scripps, containing all 

necessary small and large equipment (large equipment is described in another document, 

Major Equipment). There is more than sufficient space to carry out this project. 

Clinical. n/a 

Animal. Animals are housed in a new state-of-the-art facility of approximately 7000 square 

feet, including animal quarantine and holding rooms for rodents, dedicated procedure space, 

and a biosafety level 3 (BSL3) containment suite with shower-in requirement, biosafety 

cabinets, ventilated racks, and pass-through autoclave. Animal services are provided by a fully 

trained staff, including a full-time onsite staff veterinarian and oversight by the Scripps (La Jolla) 

head veterinarian. 

Computer. Each employee (student, technician, or post-doctoral fellow) has a dedicated 

desktop computer, and access to several other networked computers in the laboratory. The PI 

has his own computer and access to all of Scripps’ computational resources. 

Office. The PI has a ca. 175 ft. sq. private office with all necessary equipment, as well as 25% 

effort of an administrative assistant. 

Other. The Flow Cytometry Core Facility (located adjacent to the PI’s laboratory) is equipped 

with a FACS Aria high-speed, four-way cell sorter with 405, 488, and 630 nm lasers and 

sheath/sample cooling, as well as a LSR2 analytical cytometer equipped with 350, 405, 488, 

560, and 633 nm lasers. All equipment is readily accessible and so far is never used to 

capacity. The sorter is run by an institutionally-supported, trained operator, and is directed by 

the PI. All necessary equipment for proteomic analysis is located within the Proteomics Core of 

the Scripps Florida Research Institute. 

Scientific environment. The Scripps Florida campus of The Scripps Research Institute (TSRI) 

establishes a new model for academia, where the Institute provides a unique environment and 

state-of-the-art infrastructure that are needed to launch and successfully complete academiadriven drug discovery/development campaigns. Discovery research is greatly facilitated by the 

Proteomics Core (collaborative effort discussed in this application), as well as a Cell-Based 

Screening Core (genome-wide cDNA and siRNA collections of both the mouse and human 

genomes), Genomics Core (Affymetrix gene chips, Illumina Deep Sequencing, and qPCR), and 

an Ultra-High Throughput Screening Facility (with in-house and NCI small molecule libraries that 

total greater than 900,000). TSRI, of which Scripps-Florida is an integrated part, is the world's 

largest, private non-profit biomedical research facility. The six Departments at the Scripps 

Florida campus (Cancer Biology, Chemistry, Infectology, Metabolism and Aging, Molecular 

Therapeutics, and Neuroscience), join an existing nine Departments at the La Jolla campus of 

TSRI, which also houses twelve specialized Centers or Institutes and ~210 basic research 

faculty. There are synergistic interactions across all Departments and Centers of TSRI. Scripps 

Florida faculty and staff occupied three new, state-of-the-art research buildings (~390,000 total 

square feet) in November 2008 and the Institute will expand from its current roster of >40 faculty 

to eventually house ~75 faculty. The Cancer Biology Department is currently comprised of 10 

tenure-track faculty and will expand to approximately 12-13 faculty. There are currently >100 

Postdoctoral Associates at Scripps Florida and >40 (PhD- or MD-level) Staff Scientists. There 

are also 25 graduate students at Scripps Florida and this number will markedly increase over 

the next few years (there are ~220 graduate students at the La Jolla campus of TSRI). The 

TSRI Graduate Program is very highly ranked, where Ph.D. with emphases in Structural 

Biology, Chemistry, and Cell Biology, are ranked first, second, and eighth nationally, 

Facilities Page 8

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
respectively. The Max Planck Florida Institute also joined the Scripps Florida campus this year, 

and is located on the adjacent property. Research at Max Planck Florida will focus on 

bioimaging, and their arrival they will bring in new in vivo imaging technologies that will have a 

significant impact on the research programs of investigators of Scripps Florida. 

 Research Core Facilities will be shared between the two Institutes, 

and the faculty of Max Planck Florida will have the option of joint appointments at TSRI and to 

be members of the TSRI PhD Program. 

Early stage investigator: n/a 

Special facilities: n/a 

Facilities Page 9

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
MAJOR EQUIPMENT 

The PI’s laboratory has the following dedicated equipment relative to this project: Microm 

HM505E cryostat; Olympus BX40 fluorescent microscope; two high-speed refrigerated 

centrifuges; tissue culture and bio-containment hoods and CO2 incubators; a full spectrum of 

general laboratory equipment (thermocyclers, micro-centrifuges, electrophoresis apparatus, 

etc). 

The Flow Cytometry Core Facility (located adjacent to the PI’s laboratory) is equipped with a 

FACS Aria high-speed, four-way cell sorter with 405, 488, and 630 nm lasers and 

sheath/sample cooling, as well as a LSR2 analytical cytometer equipped with 350, 405, 488, 

560, and 633 nm lasers. All equipment is readily accessible and so far is never used to 

capacity. The sorter is run by an institutionally-supported, trained operator, and is directed by 

the PI. The Flow Cytometry Core also houses and maintains the Leica AMD laser 

microdissection microscope, and offers training as well as for-fee operation for less skilled 

users. 

The Microarray Core is located in a building adjacent to the one that houses the PI’s laboratory. 

Major equipment includes an Agilent Bioanalyzer 2180 with a Dell Dimension 8300 computer, a 

Nanodrop ND-1000 Spectrophotometer with a Dell Optiplex Gx280 computer, and all necessary 

Affymetrix hybridization and fluidics stations. The Bioanalyzer and Nanodrop are available to 

end-users, while the Affymetrix equipment is restricted to dedicated core personnel. 

The major computer equipment available for this project is housed and maintained by the 

Information Technology group at Scripps. This includes a high-performance 

computer cluster consisting of 200 AMD-64 processors running at 2.0 GHz, each node of which 

has 2 Gb of dual-rate RAM, providing each processor with a dedicated memory path. 

Combined with the native 64-bit capabilities of the processor, this memory path allows us to 

tackle problems of the size and complexity necessary for the proposed project. The cluster is 

tied together using a high-speed network interconnect, capable of carrying data at 1Gbit per 

second. A multi Terra-Byte storage solution is also attached. The large capacity of the storage 

arrays allows comparative and iterative work, such as that proposed in this project, to be done 

in an extremely fast manner. Data access and retrieval is accomplished with a cutting edge file 

system, able to provide data transfer speeds to disk at line speed rates (1 GBit). This oftenoverlooked aspect becomes critical when dealing with large datasets such those generated by 

the proposed project. Another unique aspect of the Scripps-Florida computer cluster is the tight 

integration of the database environment with a Storage Attached Network (SAN) environment, 

thus facilitating sharing of data in relational as well as flat file formats to the cluster with minimal 

latency. This computing power and expertise is easily sufficient to accommodate all of the 

needs of the proposed project. 

Equipment Page 10

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
Province:

PROFILE - Project Director/Principal Investigator

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Attach Current & Pending Support

RESEARCH & RELATED Senior/Key Person Profile (Expanded)

*Attach Biographical Sketch

Howard T. 

Petrie 

Professor Cancer Biology 

The Scripps Research Institute - Florida

130 Scripps Way

Jupiter

2C1

FL: Florida

USA: UNITED STATES 33458-5284

PD/PI

Ph.D.

1988

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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
BIOGRAPHICAL SKETCH 

NAME 

Petrie, Howard Terrence 

POSITION TITLE 

Professor 

eRA COMMONS USER NAME 

EDUCATION/TRAINING (Begin with baccalaureate or other initial professional education, such as nursing, and include postdoctoral training.)

INSTITUTION AND LOCATION 

DEGREE 

(if applicable) YEAR(s) FIELD OF STUDY 

Pennsylvania State University, University Park, PA BS 1974-78 Microbiology 

Pennsylvania State University, University Park, PA MS 1980-81 Microbiology 

University of Nebraska Medical Center, Omaha, NE PhD 1984-88 Immunology 

A. Personal Statement. 

I have been an independent investigator since 1993. I have been a peer reviewed, NIH funded investigator 

since 1994. My area of interest and expertise has always been the role of the thymic microenvironment on 

lymphoid progenitor differentiation. Research from my laboratory was essential in revealing the patterned 

migration of bone marrow derived progenitor cells within the thymus during differentiation. Since that time, 

we have been actively involved in further understanding the how this migration impacts the developmental 

process, as well as the mechanisms that induce or support migration. The present application is a clear 

extension of these studies. 

B. Positions and Employment. 

1978-1980 Research Technologist, Department of Microbiology, Pennsylvania State University, 

University Park, PA 

1981-1983 Technical Coordinator, Bellco Glass, Inc., Vineland, NJ 

1983-1988 Research Associate / Biological Scientist, Department of Internal Medicine /Research Service, 

The University of Nebraska and Veteran’s Administration Medical Centers, Omaha, NE 

1988-1992 Postdoctoral Fellow, Lymphocyte Differentiation Unit, The Walter and Eliza Hall Institute of 

Medical Research, Melbourne, Australia 

1992-1993 Postdoctoral Fellow, Section of Immunobiology, Yale University School of Medicine, New 

Haven, CT 

1993-2004 Assistant Member/Associate Member, Immunology Program, Sloan-Kettering Institute, 

Assistant Professor, Cornell University Graduate School of Medical Sciences, NY, NY 

2004-2005 Professor, Department of Microbiology and Immunology, University of Miami School of 

Medicine, Miami, FL 

2005-present Professor, Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL. 

Other experience:

1998-2000 Associate Editor, The Journal of Immunology 

December 2000 Guest Editor, Seminars in Immunology 

2000-2004 Section Editor, The Journal of Immunology 

2002-2006 Associate Editor, Clinical and Developmental Immunology 

C. Selected peer-reviewed publications: 

1. Petrie HT, Livak F, Schatz DG, Strasser A, Crispe IN, and Shortman K. 1993. Multiple rearrangements 

in T cell receptor γ-chain genes maximize the production of useful thymocytes. J. Exp. Med., 178:615-622. 

2. Dudley EC, Petrie HT, Shah L, Owen MJ, and Hayday AC. 1994. T cell receptor β chain gene 

rearrangement and selection during thymocyte development in adult mice. Immunity 1:83-93. 

3. Wayne J, Suh H, Sokol KA, Petrie HT, Witmer-Pack M, Edelhoff S, Disteche CM and Nussenzweig MC. 

1994. TCR selection and allelic exclusion in RAG transgenic mice that exhibit abnormal T cell localization in 

lymph nodes and lymphatics. J. Immunol. 153:5491-5502. 

4. Livak F, Petrie HT, Crispe IN, and Schatz DG. 1995. In-frame TCR-δ gene rearrangements play a 

critical role in the αβγδ T cell lineage decision. Immunity 2:617-628. 

5. Petrie HT, Livak F, Burtrum D, and Mazel S. 1995. TCR gene recombination patterns and mechanisms: 

cell death, rescue, and T cell production. J. Exp. Med. 182:121-127. 

Biosketches Page 13

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
6. Mazel S, Burtrum D, and Petrie HT. 1996. Regulation of cell division cycle progression by bcl-2: a 

potential mechanism for the inhibition of programmed cell death. J. Exp. Med. 183:2219-2226. 

7. Burtrum DB, Kim S, Dudley EC, Hayday AC, and Petrie HT. 1996. TCR gene recombination and αβγδ 

lineage divergence: productive TCR-β rearrangement is neither exclusive nor preclusive of γ/δ cell 

development. J. Immunol. 157:4293-4296. 

8. Tourigny M, Mazel S, Burtrum DB, and Petrie HT. 1997. TCR-β gene recombination: dissociation from 

cell cycle regulation and developmental progression during T cell ontogeny. J. Exp. Med: 185:1549-1556 

9. Murgia C, Blaikie P, Kim N, Dans M, Petrie HT, and Giancotti F. 1998. A targeted deletion of the integrin 

β4 cytoplasmic domain causes separate cell adhesion and cell cycle defects. EMBO J. 17:3940-3951. 

10. Livak F, Tourigny M, Schatz DG, and Petrie HT. 1998. Characterization of T cell receptor (TCR) gene 

rearrangements during adult murine T cell development. J. Immunol.162:2575-2580. 

11. Lind E, Wayne J, Wang Q-Z, Staeva T, Stolzer A, and Petrie HT. 1999. Bcl-2-induced changes in E2F 

regulatory complexes reveal the potential for integrated cell cycle and cell death functions. J. Immunol. 

162:5374-5379. 

12. King LB, Tolosa E, Lu F, Lenczowski JM, Lind EF, Hunziker R, Petrie HT, and Ashwell JD. 1999. A 

Dominant-negative mutant of c-Jun inhibits cell cycle progression during the transition of CD4- 8- to CD4+8+

thymocytes. Int. Immunol. 11:1203-1216. 

13. Petrie HT, Tourigny M., Burtrum DB., Mazel S., and Livak F. 2000. Precursor thymocyte differentiation 

and proliferation are controlled by microenvironmental signals unrelated to the pre-TCR. J Immunol. 

165:3094-3098.

14. Livak F, Burtrum DB, Rowen L, Schatz DG, and Petrie HT. 2000. Genetic modulation of TCR gene 

segment usage during somatic recombination. J. Exp. Med. 192: 1191-1196. 

15. Lind E, Prockop S, Porritt H, and Petrie HT. 2001. Mapping precursor movement through the post-natal 

thymus reveals specific microenvironments supporting defined stages of early lymphoid development. J. 

Exp. Med. 194:127-134. 

16. Yannoutsos N, Wilson P, Yu W, Chen HT, Nussenzweig A, Petrie HT, and Nussenzweig MC. 2001. The 

role of recombination activating gene (RAG) reinduction in thymocyte development in vivo. J. Exp. Med. 

194:471-80. 

17. Prockop S, Palencia S, Ryan CM, Gordon K, Gray D, and Petrie HT. 2002. Stromal cells provide the 

adhesion matrix for migration of early lymphoid progenitors through the thymic cortex. J. Immunol. 

169:4354-4561. 

18. Gordon K, Duckett L, Daul B, and Petrie HT. 2003. A simple method for detecting up to five 

immunofluorescent parameters together with DNA staining for cell cycle or viability on a benchtop flow 

cytometer. J. Immunol..Methods, 275:113-21. 

19. Lepique AP, Palencia S, Irjala H, and Petrie HT. 2003. Characterization of vascular adhesion molecules 

that may facilitate progenitor homing in the post-natal mouse thymus. Clin. Dev. Immunol. 10:27-33. 

20. Porritt H, Gordon K, and Petrie HT. 2003. Kinetics of steady-state differentiation and mapping of 

intrathymic signaling environments by stem cell transplantation in non-irradiated mice. J. Exp. Med. 

198:957-62. 

21. Plotkin J, Prockop SE, Lepique A, and Petrie HT. 2003. Critical role for CXCR4 signaling in progenitor 

localization and T cell differentiation in the post-natal thymus. J. Immunol. 171:4521-7. 

22. Prockop SE, and Petrie HT. 2004. Functional assessment of alphaEbeta7/E-cadherin interactions in the 

steady state postnatal thymus. Clin. Dev. Immunol. 11:135-41. 

23. Prockop SE, and Petrie HT. 2004. Regulation of thymus size by competition for stromal niches among 

early T cell progenitors. J. Immunol, 173:1604-11. 

24. Schmitt TM, Ciofani M, Petrie HT, Zuniga-Pflucker JC. 2004. Maintenance of T cell specification and 

differentiation requires recurrent notch receptor-ligand interactions. J. Exp. Med. 200: 469-79. 

25. Misslitz A, Pabst O, Hintzen G, Ohl L, Kremmer E, Petrie HT, Forster R. 2004. Thymic T cell 

development and progenitor localization depend on CCR7. J. Exp. Med. 200: 481-91. 

26. Tabrizifard S, Olaru A, Plotkin J, Fallahi-Sichani M, Livak F, and Petrie HT. 2004. Analysis of 

transcription factor expression during discrete stages of post-natal thymocyte differentiation reveals 

potentials novel regulators of differentiation and proliferation. J. Immuol,. 173:1094-102. 

27. Porritt HE, Schmitt TM, Rumfelt LL, Tabrizifard S, Zuniga-Pflucker JC, and Petrie HT. 2004. 

Heterogeneity among DN1 prothymocytes reveals multiple progenitors with different capacities to generate T 

cell and non-T cell lineages. Immunity, 20:735-45. 

28. Huang J, Garrett KP, Pelayo R, Zúñiga-Pflücker JC, Petrie HT, Kincade PW. 2005. Propensity of adult 

lymphoid progenitors to progress to DN2/3 stage thymocytes with Notch receptor ligation. J. Immunol, 

175:4858-4865 

Biosketches Page 14

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
29. Schwartz R, Engel I, Fallahi-Sichani M, Petrie HT, and Murre C. 2006. Gene expression patterns define 

novel roles for E47 in cell cycle progression, cytokine-mediated signaling, and T lineage development. Proc. 

Natl. Acad. Sci. (USA) 103:9976-81. 

30. Petrie HT and Zuniga-Pflucker JC. 2007. Zoned out: functional mapping of stromal signaling 

microenvironments in the thymus. Annu Rev Immunol 25:649-79. 

31. Umland O, Mwangi W, Anderson B, Walker J, and Petrie HT. 2007. The Blood Contains Multiple Distinct 

Progenitor Populations with Clonogenic B and T Lineage Potential. J Immunol 178:4147-4152. 47. 

32. Gosink MM, Petrie HT, and Tsinoremas NF. 2007. Electronically subtracting expression patterns from a 

mixed cell population. Bioinformatics 23:3328-3334. 

33. Griffith AV, Fallahi M, Nakase H, Gosink M. 2009. Young B, and Petrie HT. Spatial mapping of thymic 

stromal microenvironments reveals unique features influencing T lymphoid differentiation. Immunity 31:999-

1009. PMCID PMC2807413. 

D. Research Support: 

Ongoing. 

1R01AG031576 Petrie (PI) 02/01/09 - 01/31/14 

Identification of stromal responses during castration-induced thymic regrowth. 

The major goals of this project are to use our recently devised differential gene mapping approach (see 

Griffith et al., above) to measure gene expression changes in young thymic stromal cells, old thymic stromal 

cells, and thymic stromal cells undergoing regeneration in response to surgical castration. These gene 

expression changes will then be used to identify growth and survival pathways in stromal cells, and to probe 

their biology. The informatic methodologies used in this project are exactly those that are required for the 

current proposal. 

Completed. 

1R21AI067453 Petrie 01/15/06 -12/31/07 

Transcriptional Mapping of Thymic Stromal Microenvironments 

The major goals of this project were to use tissue microdissection and global gene expression profiling to 

characterize thymic stromal cells from functionally-defined tissue sub-regions of the thymus, and to identify 

subregion-specific signals that induce specific developmental events in progenitor T cells. The skills and 

knowledge gained during the execution of this project are completely and uniquely relevant to the current 

proposal. 

1R21AI053739 Petrie 01/01/03 - 12/31/04 

Signals for lineage commitment in the post-natal thymus 

The major goals of this project were to use microarray profiling of RNA from purified progenitor thymocytes to 

identify genes, and particularly, surface receptors, that change during lymphoid development in the thymus. 

The biological and informatic techniques developed for this project are exactly those that will be used for the 

current project. 

Biosketches Page 15

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PHS 398 Cover Page Supplement

1. Project Director / Principal Investigator (PD/PI)

* Title:

* Street1:

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Person to be contacted on matters involving this application

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Province:

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Howard

T. 

Petrie 

No Yes

No Yes

Kaye

I.

Wynne

V.P., Office of Sponsored Programs

10550 North Torrey Pines Road

TPC-7

La Jolla

USA: UNITED STATES

CA: California

92037-1000

	


 		

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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
4. Human Embryonic Stem Cells

* Does the proposed project involve human embryonic stem cells?

If the proposed project involves human embryonic stem cells, list below the registration number of the 

specific cell line(s) from the following list: http://stemcells.nih.gov/research/registry/. Or, if a specific 

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registry will be used: 

Specific stem cell line cannot be referenced at this time. One from the registry will be used.

PHS 398 Cover Page Supplement

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Clinical Trial & HESC Page 17

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PHS 398 Modular Budget, Periods 1 and 2

OMB Number: 0925-0001 

1. 

Start Date: End Date:

Budget Period: 1

* Direct Cost less Consortium F&A

A. Direct Costs

B. Indirect Costs

Consortium F&A

* Total Direct Costs

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Indirect Cost 

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Indirect Cost 

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3. 

4. 

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07/01/2011 06/30/2012

MTDC 94.5

HHS Region IX 

DHHS, Division of Cost Allocation 

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San Francisco, CA 94103-6701 

(415) 437-7820 

10/14/2009

C. Total Direct and Indirect Costs (A + B) Funds Requested ($)

1. 

Start Date: End Date:

Budget Period: 2

* Direct Cost less Consortium F&A

A. Direct Costs

B. Indirect Costs

Consortium F&A

* Total Direct Costs

Indirect Cost Type

Indirect Cost 

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Indirect Cost 

Base ($) * Funds Requested ($)

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Indirect Cost Rate Agreement Date Total Indirect Costs

C. Total Direct and Indirect Costs (A + B) Funds Requested ($)

2. 

3. 

4. 

* Funds Requested ($)

MTDC 94.5

HHS Region IX 

DHHS, Division of Cost Allocation 

90 7th Street 

San Francisco, CA 94103-6701 

(415) 437-7820

10/14/2009

07/01/2012 06/30/2013

	


 		

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Modular Budget Page 18

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PHS 398 Modular Budget, Periods 3 and 4

1. 

Start Date: End Date:

Budget Period: 3

* Direct Cost less Consortium F&A

A. Direct Costs

B. Indirect Costs

Consortium F&A

* Total Direct Costs

Indirect Cost Type

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Base ($) * Funds Requested ($)

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2. 

3. 

4. 

1. 

Start Date: End Date:

Budget Period: 4

* Direct Cost less Consortium F&A

A. Direct Costs

B. Indirect Costs

Consortium F&A

* Total Direct Costs

Indirect Cost Type

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Rate (%)

Indirect Cost 

Base ($) * Funds Requested ($)

Cognizant Agency (Agency Name, POC Name and Phone Number)

Indirect Cost Rate Agreement Date Total Indirect Costs

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2. 

3. 

4. 

* Funds Requested ($)

* Funds Requested ($)

	


 		

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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PHS 398 Modular Budget, Periods 5 and Cumulative

1. 

Start Date: End Date:

Budget Period: 5

* Direct Cost less Consortium F&A

A. Direct Costs

B. Indirect Costs

Consortium F&A

* Total Direct Costs

Indirect Cost Type

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Indirect Cost Rate Agreement Date Total Indirect Costs

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2. 

3. 

4. 

Cumulative Budget Information

* Funds Requested ($)

*Section A, Total Direct Cost less Consortium F&A for Entire Project Period

1. Total Costs, Entire Project Period

Section A, Total Consortium F&A for Entire Project Period

*Section A, Total Direct Costs for Entire Project Period

*Section B, Total Indirect Costs for Entire Project Period

*Section C, Total Direct and Indirect Costs (A+B) for Entire Project Period

2. Budget Justifications

 $

 $

 $

 $

 $

Personnel Justification

Consortium Justification

Additional Narrative Justification

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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PERSONNEL JUSTIFICATION 

Howard T Petrie, Ph.D. Principal Investigator. 1.2 calendar months. Note that the PI is 

required to generate 100% support for his own salary and fringe benefits, as well 

100% of the salary and fringe benefits of his employees and/or trainees. The PI will be 

solely responsible for project oversight. This includes supervising and training the postdoctoral fellow (100% effort, below) in both biological and informatic techniques, and 

supervising the informatic specialist (10% effort, below), and the interactions between these 

two individuals. Where necessary (historically, very frequently), the PI will directly assist in 

biological procedures, either to help to move projects more rapidly to completion, or for the 

purposes of demonstration and training for the PDF. The PI will also be responsible for noncompetitive renewal application (s), animal protocols, and other reporting requirements. The 

PI will monitor the budget to ensure that the project remains within the range available 

resources. The PI will review all raw data in detail prior to submission for publication, and 

will write the manuscripts that result. The PI, and/or the post-doctoral fellow, may also be 

responsible for presenting the data at conferences. 

To be named, Ph.D. Post-doctoral fellow. 12 calendar months. The post-doctoral fellow 

will carry out the majority of the biological and informatic procedures described in this 

proposal, with assistance and training from the PI and the informatic scientist (below). The 

PDF will interact closely with the PI to develop biological insights and revise the approach as 

necessary. The PDF will be responsible for organizing data into a state that is 

comprehensible for review by the PI for progress reports and publication, and may assist in 

the writing of manuscripts. The PDF may be responsible for presentation of the data at 

conferences. Note that at the completion of this project, the PDF will possess a very 

desirable set of skills that involve thymus biology, genetic modeling, and informatic data 

mining. These skills are very relevant for the future, and will greatly benefit the PDF in the 

development of his/her career. 

Mohammad Fallahi, M.S. Informatic Scientist. 1.2 calendar months. The informatic 

scientist is currently shared between the PI and two other investigators at Scripps. He does 

not, himself, have adequate additional effort available to devote to the proposed project: 

months 7 through 12 (approximately) of the proposed project will require a 100% effort for 

processing the data generated during months 1-6. During the entire project, the PDF will 

receive hands-on training from the informatic scientist, and training and supervision from the 

PI, to develop the skills to go from raw microarray data to candidate receptor:ligand 

interactions for biological validation (year 2). The informatic scientist has worked with the PI 

for more than 7 years, and is very skilled in the relevant techniques, as well as being a 

skilled and patient teacher. 

Personnel Justification Page 21

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
PHS 398 Research Plan

1. Application Type:

From SF 424 (R&R) Cover Page. The response provided on that page, regarding the type of application being submitted, is repeated for your 

reference, as you attach the appropriate sections of the Research Plan.

*Type of Application:

OMB Number: 0925-0001 

2. Specific Aims

3. *Research Strategy

6. Protection of Human Subjects

7. Inclusion of Women and Minorities

8. Targeted/Planned Enrollment Table

9. Inclusion of Children

10. Vertebrate Animals

13. Consortium/Contractual Arrangements

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16. Appendix

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(for RESUBMISSION or REVISION only)

Human Subjects Sections

2. Research Plan Attachments: 

 Please attach applicable sections of the research plan, below.

Other Research Plan Sections

5. Progress Report Publication List

11. Select Agent Research

12. Multiple PD/PI Leadership Plan

4. Inclusion Enrollment Report

New Resubmission Renewal Continuation Revision

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List of Research Plan Attachments Page 22

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
SPECIFIC AIMS

Like all blood cells, T lymphocytes are constantly lost during life, and must be continuously replaced. The 

thymus is the primary site of de novo T lymphopoiesis. Microenvironmental conditions unique to the thymus 

induce a complex series of developmental events in multipotent, marrow-derived progenitors, including positive 

and negative control of proliferation, T lineage specification, functional T lineage asymmetry, self-restriction, 

self-tolerance, and cell death/survival signals. Significant progress has been made in understanding the 

signals the thymus provides to lymphoid progenitors to induce and control these events. However, the 

proliferation, differentiation, and compartmentalization of the non-lymphoid (stromal) components of the thymus 

are equally dependent on lymphoid cells, and the absence of lymphoid cells (e.g., congenital 

immunodeficiency diseases) results in athymia, even though the nascent stromal cells are functionally 

competent. The signals that lymphoid cells provide to induce stromal growth, differentiation, and/or survival 

are completely unknown. In this proposal, we propose to address this process in a comprehensive fashion, 

as described in the following Aims: 

AIM 1. DEFINE DYNAMIC CHANGES IN GENE EXPRESSION IN STROMAL CELLS IN AN INDUCIBLE MODEL OF THYMIC 

ORGAN GROWTH. In this Aim, we will use an inducible model of thymus growth and our recently published 

approach for analyzing stromal gene expression in situ (Griffith et al., 2009) to characterize stromal responses 

to lymphoid progenitor cells at the gene expression level. The in vivo model system is represented by IL7R-/-

mice (Peschon et al., 1994), which are athymic but exhibit robust growth in response to transplanted wildtype 

lymphoid cells (Prockop and Petrie, 2004). Importantly, no marrow conditioning is required for donor cell 

engraftment in IL7R-/- mice (Prockop and Petrie, 2004), eliminating the adverse effects that chemical or 

radiological agents have on thymic stroma. Stromal gene expression will be analyzed at key time points in the 

growth response, corresponding to growth induction, log phase growth, termination of growth, and steadystate; 

AIM 2. IDENTIFY STROMAL RECEPTOR:LYMPHOID LIGAND PAIRS AMONG GENES EXPRESSED DURING INDUCED 

THYMIC GROWTH. Aim 1 will focus on the characterization of gene expression profiles in stromal cells during 

lymphoid-induced growth. In the second phase of the project, we will identify stromally expressed genes that 

encode receptors, and thus may be responsible for interpolating responses to lymphoid-derived signals. We 

will further assess the validity of this stromal receptor gene list by verifying the presence of the corresponding 

ligand in lymphoid cells at corresponding phases of the growth response; 

AIM 3. PRIORITIZE CANDIDATE LYMPHOID → STROMAL SIGNALS. Multiple metrics will be applied to prioritize the 

list of candidate signal axes. Various quantitative (score-based) metrics will include frequency of 

receptor:ligand co-citation (higher co-citation indicates greater biological relevance), frequency of co-citation of 

receptor or ligand in reference to the thymus (low thymus citations are potentially more interesting, especially 

for those with high co-citation scores), co-occurrence in public databases, experimental evidence (database 

driven), and ANOVA p value (for the dynamic response range of individual receptors). An overall priority score 

will be derived using a combination of these quantitative metrics, although individual scores may be used 

independently. Qualitative assessments will also be applied, including availability of genetic mutant resources, 

modulatory compounds or molecular reagents, or analytical reagents. All metrics will be developed 

computationally, and merged into a single database, including hypertext links to the relevant resources 

(literature citations, experimental databases, mouse mutant model repositories, etc.). Final priorities will be 

determined by manually evaluating qualitative metrics in the context of the highest scoring candidates from 

quantitative analysis, with particular emphasis on the availability of mouse models; 

AIM 4. ESTABLISH BIOLOGICAL RELEVANCE FOR ONE OR MORE HIGH-PRIORITY LYMPHOID → STROMAL SIGNALS. 

The above Aims will provide a prioritized list of potential candidate lymphoid → stromal signals. For a select 

number of the best candidates (i.e., those with the highest quantitative scores and best qualitative metrics and, 

in particular, the availability of genetic models), we will perform biological validation by evaluating thymic size 

and composition directly in receptor (stromal) or ligand (lymphoid) mutant mouse models. These will establish 

proof of concept, as well as leading to hypothesis driven, mechanistic approaches to understanding the 

interplay between lymphoid and stromal cells in the thymus.  

Specific Aims Page 23

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
SIGNIFICANCE. 

T lymphocytes are constantly lost throughout life to a variety of causes (bleeding, senescence, 

activation/contraction). Although the thymus is the primary site of steady state T lymphopoiesis, no selfrenewing stem/progenitor cells are found within the thymus (Goldschneider et al., 1986; Scollay et al., 1986). 

Instead, ongoing lymphopoiesis in the thymus depends on the active recruitment of multipotent, bone 

marrow-derived progenitor cells found circulating in the blood. Once inside the thymus, a unique set of 

microenvironmental signals specifies the T lineage fate in these uncommitted progenitors, and induces them 

to undergo a well-defined series of developmental events leading to the production of functional T

lymphocytes. Much has been learned regarding the influence of the thymic stromal microenvironment in this 

process (reviewed in Petrie and Zuniga-Pflucker, 2007). However, the almost exclusive focus on signals from

the thymic microenvironment to lymphoid cells is somewhat myopic, since lymphoid cells themselves, as the 

dominant cell type in the thymus, must play a major role in establishing the overall microenvironment. A 

widely recognized example of this is provided by the phenomenon commonly known as “crosstalk” (reviewed 

in van Ewijk et al., 1994), in which the stromal cells of the thymus depend on the presence of developing 

lymphoid cells for their own proliferation, differentiation, and/or survival (van Ewijk et al., 2000). The absence 

of lymphoid cells results in profound changes in thymic structure, and disruption of organ structure results in 

correspondingly profound changes in stromal cells, most notably including down-regulation of the crucial

Notch ligands (Mohtashami and Zuniga-Pflucker, 2006). Evidence for stromal dependence on lymphoid cells 

is also provided by human (mainly pediatric) patients with severe combined immunodeficiency disorder 

(SCID); such patients are athymic, but transplantation of normal hematopoietic stem cells generally results in 

the formation of a nearly normal, functional thymus (reviewed in Fischer et al., 2005). Thus, lymphoid cells 

are required for normal stromal proliferation, differentiation, survival, and function, which, in turn, are required 

for continuous production of lymphocytes during post-natal life.

Notably, the signals that lymphoid cells provide to stromal cells to induce their proliferation, 

differentiation, and/or survival are completely unknown. As mentioned above, the historical perspective 

of the thymus is lympho-centric, a view that is understandable since production of lymphoid cells is the main 

function of the thymus. This perspective is further exacerbated by the ease with which lymphoid and other 

hematopoietic cells are manipulated in experimental systems; in contrast, isolation and manipulation of 

thymic stromal cells is quite challenging, particularly in the hypotrophic state that accompanies lymphoid 

immunodeficiencies. To meet this challenge, we have devised a computational method for global

identification of stromal gene expression in situ (Griffith et al., 2009). In brief, RNA isolated from 

microdissected tissue (cortex, medulla, or any other region of interest) is used to measure gene expression 

using cDNA microarrays. Simultaneously, gene expression in the lymphocytes that correspond to that region 

(isolated from other thymuses) is also measured by microarray. Stromal gene expression can be defined as 

gene expression in the tissue that is not attributable to gene expression by the corresponding lymphoid cells. 

The validity of this approach has been demonstrated by its ability to capture virtually all of the genes that are 

known to characterize stromal cells in the (young) thymus, including known stromal signals for developing 

lymphoid cells (e.g., Notch ligands, IL7, kit ligand, Cxcl12, MHC 

proteins, etc.), as well as genes known to be intrinsically required for 

stromal development or function (e.g., Foxn1, Pax1, Egfrs, etc.). This 

approach has several advantages over conventional approaches to 

studying thymic stromal cells. For one, there are no changes in gene 

expression caused by disruption of the 3D context of the thymus, or by

enzymatic digestions or lengthy incubations at 37o

C. This approach is 

also non-biased, and returns information on all of the stromal cells in a 

given region (the exact identify can be established later, using 

immunohistochemistry, RNA in situ hybridization, etc.). Most 

importantly for the current proposal, this approach requires very little 

tissue, and thus is amenable to the study of stromal cells in 

hypotrophic or atrophied tissues, such as the one proposed here (see 

Fig.1).

The goal of the current proposal is to understand how thymic stromal 

cells respond to the presence of lymphoid cells by activating latent 

pathways for growth, differentiation, and/or survival. We will focus on

stromal receptor:lymphoid ligand interactions. Since stromal cells 

clearly and undeniably respond to the presence of lymphoid cells by 

Research Strategy Page 24

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
proliferation and differentiation (for an example, see Penit et al., 1996), such interactions must exist. The 

model system we will use is represented by IL7R-deficient mice (Peschon et al., 1994) that have been 

injected with wildtype lineage-negative bone marrow, as previously described by our group (Prockop and 

Petrie, 2004). Several advantages of this model system make it ideal for the purpose of this project. First, the 

stromal cells themselves are inherently normal in IL7R-/-

 mice, and only the lymphoid cells are affected by 

mutation of the IL7R. Second, the IL7R-/-

 thymus undergoes profound growth in response to the presence of 

normal stem/progenitor cells (Prockop and Petrie, 2004), which is the function that is to be studied. Third, this 

response can be induced without the need for myeloablative conditioning of recipient mice (Prockop and 

Petrie, 2004), and thus, the damaging effects of ablative regimens on thymic stromal cells (reviewed in Heng 

et al., 2010) will be avoided. Finally, the (unmanipulated) IL7R-/-

 thymus contains visible and organized (albeit 

hypotrophic) cortical and medullary regions, whereas other immunodeficient mouse models do not (for an 

example, see Prockop and Petrie, 2004). This characteristic allows us to establish baseline gene expression 

in stromal cells from a hypotrophic thymus, from which point changes that occur in response to an expanding 

lymphoid population will be measured.

Understanding how lymphoid cells induce thymic stromal responses has been a subject of contemplation for 

many laboratories for many years. However, given the difficulties associated with thymic stromal cell isolation 

(described earlier), and the further limitation imposed by the small number of cells present in the 

immunodeficient thymus, it has been a very difficult issue to address. The combination of our stromal gene 

mapping approach (Griffith et al., 2009), together with the IL7R-/-

 growth model (Prockop and Petrie, 2004),

now gives us the opportunity address this issue in a comprehensive manner. The methods have already 

been established and documented in peer-reviewed publications, and thus, no lengthy methodological 

development will be necessary. So little is known about how stromal cells respond to the presence of 

lymphocytes that even a few clues regarding this process would be a major advancement. Instead, we 

propose to characterize this response in global detail, with the intention of publishing the results of these 

gene expression studies, as well as probing the molecular mechanisms of this response in biological model 

systems.

Our goal is to characterize how lymphoid cells induce stromal growth, differentiation, and/or survival in the 

fully formed (but hypocellular) thymus. We wish to emphasize that this is distinct from the somewhat related 

functions that occur during embryonic organogenesis of the thymus, including specification of the thymic 

primordium (which is lymphoid-independent), and divergence of cortical and medullary stromal lineages. 

While the approach described in this project may be suitable for probing those questions, they are distinctly 

different, and should not be confused with the goals of the current project, which is to understand the signals 

that induce growth, differentiation, and/or survival of stromal cells after the nascent organ has been formed.

INNOVATION.

As described above, the vast majority of studies on the thymus have focused on the role that the stromal

microenvironment plays in supporting lymphoid differentiation. In contrast, the role that the lymphoid cells 

play in establishing the overall microenvironment is very poorly understood. In particular, the mechanism by 

which stromal cells respond to the presence of lymphoid cells by undergoing proliferation and post-mitotic 

differentiation (Penit et al., 1996) is virtually unknown. This project seeks to address this paucity in a 

comprehensive and physiologically relevant fashion, and therefore is both novel and innovative. Further, the 

experimental approaches (in situ stromal gene mapping in a non-myeloablative model system of induced

thymic growth) are technologically novel. The combination of these techniques seems highly likely to provide 

a wealth of information on this biologically important question with little risk of failure, given that these 

technologies are already very well established in our laboratory.

APPROACH.

AIM 1. DEFINE DYNAMIC CHANGES IN GENE EXPRESSION IN STROMAL CELLS IN AN INDUCIBLE MODEL OF THYMIC 

ORGAN GROWTH. The goals of this Aim are to use our differential stromal gene mapping approach (Griffith et 

al., 2009) in an inducible model of growth (intravenously transplanted IL7R-/-

 mice, Prockop and Petrie, 2004)

to identify the genes expressed by stromal cells during the response to the influx and expansion of lymphoid 

cells. We will isolate intact cortical and medullary regions from one lobe of the thymus from 4 week-old IL7R-/-

(male) mice, and simultaneously, will sort cortical (CD3-/lo AND CD45+

 AND (CD90+ OR CD117+)) and 

medullary (CD3hi CD45+

) lymphoid cells from the other lobe. We will perform 3 independent microarrays for 

each sample type (cortical or medullary, tissue or lymphoid), and each microarray will represent pooled RNA 

Research Strategy Page 25

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
from 3 individual mice. We will repeat this entire procedure at key points 

after intravenous injection of 2.5 x 106

 wildtype lineage-negative bone 

marrow cells (Prockop and Petrie, 2004); the points will be chosen to 

represent the time at which thymic growth is first initiated, the time at which 

thymus size reaches its peak, a time point intermediate to these, and a 

time point approximately 36 hours before the peak (Fig.2). Functionally, 

these correspond to baseline (untransplanted), growth initiation, steadystate (although some overshoot is expected), log phase growth, and 

termination of growth, respectively. The significance of most of these time 

points is hopefully obvious. The “termination of growth” time point may 

warrant some additional explanation, since this time point is not really 

essential to understanding the growth process. However, the molecular 

mechanisms for how size is limited in any organ are still poorly understood, 

especially in vertebrates. Consequently, the simple addition of this time 

point will allow us to identify the changes that precede the cessation of 

organ growth, and how these differ from the steady state, thus greatly 

expanding the overall impact and potential implications of the project.

Although we have shown that the IL7R-/- thymus responds to the presence of wildtype lymphocytes by robust 

growth (Prockop and Petrie, 2004), we do not know the precise kinetics of this response. Since the precise 

timing of the analytical intervals illustrated in Fig.2 is relatively important, we will first perform preliminary 

experiments to determine the kinetics of induced growth in this model. Based on existing knowledge 

regarding the kinetics of fetal thymic growth (about 10 days, assuming formation of the primordium around 

e10), the kinetics of one complete wave of post-natal T cell development (about 20 days, see Porritt et al., 

2003; Shortman et al., 1990), and the partial kinetics of reconstitution in RAG-deficient mice (about 20+ days, 

see Penit et al., 1996), we will perform an initial series of kinetic analyses in which the size of the thymus in 

IL7R-/- mice will be measured 0, 4, 8, 12, 16, 20, 24, 28, and 32 days after transplantation with wildtype cells. 

This will involve 3 mice at each time point, transplanted with 2.5 x 106

 lineage-depleted, wildtype bone 

marrow cells. We expect that a second kinetic series will need to be performed, including serial 1-day time 

points just prior to the point at which the onset of growth is observed in the first experiment (to more precisely 

determine when this process begins), as well as on both sides of the peak (to determine when the peak 

actually occurs and, by definition, the “termination of growth” time point). From these experiments, we will 

proceed with the kinetic analysis illustrated in Fig.2 and described above.

Using the statistical and computational methods previously described by us (Griffith et al., 2009), we will 

identify stromal gene expression at each stage of the growth process by comparing gene expression in 

purified cortical or medullary lymphocytes to that of the corresponding tissue. Once stromal gene expression 

levels have been calculated for each gene (probeset) on the chip (Affymetrix MOE430_2, representing all 

genes and ESTs), we will set arbitrary thresholds to distinguish genes that are expressed from those that are 

not. The conventional threshold for this purpose is the median signal value, which operates under the 

assumption that any given cell type expresses roughly 50% of all genes in the genome. However, since gene 

expression signals exhibit a Poisson distribution, the use of any arbitrary threshold to establish a binary 

outcome (expressed/not expressed) is inherently flawed (i.e., some genes below the threshold are actually 

expressed, and some genes above the threshold are not). Consequently, while the 50th percentile will be 

used as a default present/absent threshold, we may also apply different thresholds (40th or 60th percentile) to 

increase or decrease stringency, depending on the outcomes and objectives (see further discussion in Aim 

3). Note that present/absent detection calls (determined by the weighted statistical difference between signals 

for perfect match and single base mismatched probes in each probeset) cannot be accurately used for 

calculated stromal signals, since they cannot distinguish lymphoid from stromal gene expression in 

microdissected tissue. However, they can be used to eliminate genes that are not expressed at all in the 

thymus; probesets where <2 (out of 3) present detection calls are found in any given tissue will be flagged, 

since these are unlikely to be present in either lymphoid or stromal cells. Further, genes with ≥2 present calls 

in tissue AND <2 present calls in lymphoid cells will also be flagged, as these are likely to represent stromal 

specific genes (i.e., they are expressed in tissue, but not in the lymphoid component of the tissue), an 

important subset of all stromal genes (Griffith et al., 2009). The identification of all genes expressed by 

stromal cells during lymphoid-induced growth, as described above, will subsequently be used to identify 

stromal receptors that may detect the presence of lymphoid cells, and/or transduce a response to lymphoidderived signals, as described in Aim 2.

Research Strategy Page 26

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
It is important to consider that the (young) IL7R-/-

 thymus contains some (IL7R-/-) lymphoid cells, and gene 

expression signatures in these lymphoid cells are expected to be quite different than that of wildtype cells. 

Thus, the lymphoid signal in the reconstituted thymus will gradually shift from an IL7R-/- signature to a 

combination of IL7R-/-

 and wildtype, and then to essentially all wildtype. This will not impair our ability to 

identify stromal gene expression in these tissues, because we will not be comparing lymphoid gene 

expression between time points (which would certainly reveal differences in the context of a growing thymus, 

even if only wildtype cells were present). Instead, data from lymphoid cells will only be used to identify the 

stromal component of gene expression in tissue at the corresponding time point, i.e., an internally matched 

comparison. Once stromal signatures have been established at each time point, stromal-to-stromal changes 

over time will be evaluated. Lymphoid gene expression may be re-queried at that point to determine whether 

relevant ligands are expressed (see Aim 2). However, lymphoid cells will not be compared to each other 

across different time points, and thus, differences in gene expression between IL7R-/-

 and wildtype lymphoid 

cells are irrelevant. It is also important to consider why the IL7R-/-

 lymphoid cells that are present in 

unmanipulated IL7R-/-

 thymuses do not stimulate stromal growth. This stems from the fact that most 

lymphocytes in the thymus of young IL7R-/-

 mice are the remnants of fetal hematopoietic development 

(originating in the liver); since fetal thymocytes do not depend on IL7 (for example, see Balciunaite et al., 

2005), the fetal thymus in IL7R-/-

 mice can form and compartmentalize, but the continued growth that 

accompanies the arrival of definitive progenitors is absent. In fact, by a later age (~10 weeks), IL7R-/-

 mice 

exhibit an almost complete arrest at the DN2 stage of development (Crompton et al., 1998), consistent with 

high levels of IL7R expression at that stage in normal mice (Allman et al., 2003; Porritt et al., 2004). Thus, the 

lymphoid component of the thymus in young IL7R-/-

 mice is actually collapsing, resulting in stromal 

degeneration and a profoundly hypoplastic organ that can nonetheless be rescued by wildtype progenitor 

cells (Prockop and Petrie, 2004). It is this response that we seek to characterize.

AIM 2. IDENTIFY STROMAL RECEPTOR:LYMPHOID LIGAND PAIRS AMONG GENES EXPRESSED DURING INDUCED 

THYMIC GROWTH. The data generated in Aim 1 will provide a list of all genes expressed in stromal (and 

lymphoid) cells during the induced growth process. In this Aim, we will identify those stromally expressed

genes that encode receptor proteins, and then verify the presence of the corresponding ligand (or counterreceptor) in the lymphoid population. We will merge two independent approaches for this objective. The first 

utilizes the Human Plasma Membrane Receptome database (www.receptome.org/HPMR). Most 

protein:protein interaction and signaling resources do not focus on receptor-ligand interactions (e.g. 

www.signaling-gateway.org), or only include a subset of receptor:ligand interactions (http://dip.doembi.ucla.edu/dip/DLRP.cgi). In contrast, the HPMR resource is a comprehensive database of more than 900 

receptors and 600 paired ligands; this database was built using proteomic sequence analyses (multi 

alignments and domain associations), followed by manual curation of each record with information from 

the literature (Ben-Shlomo et al., 2003). In order to speed our batch query and gene mapping needs, the 

HPMR group has provided us with their entire database (see letter of support), including MOE430_2 (mouse) 

probeset IDs that will allow us to easily identify receptors expressed in our kinetic database of stromal growth, 

and likewise for lymphoid data. This powerful database virtually assures success in identifying a large variety 

of receptor:ligand interactions, even without other parallel approaches.

The second approach uses Boolean combinations of gene ontology terms (primarily molecular function 

ontologies), together with automated searching of literature resources (PubMed, PubMed Central), to identify

co-occurrence of receptor:ligand terms (gene symbols and aliases) in published literature. To generate our 

own list of receptors and ligands, we developed a manually curated list of well known genes corresponding to 

those function, and used them to model a Boolean hierarchy of gene ontologies that included as many of our

genes as possible, while simultaneously excluding inappropriate genes (noise). For instance, a list of

receptors was built from the ontologies “receptor activity (004872) OR receptor complex (043235) OR plasma 

membrane (005886) OR intrinsic to membrane (031224) OR integral to membrane (016021) OR external 

side of plasma membrane (009897) OR cell surface (009986)], but NOT [golgi apparatus (005794) OR 

endoplasmic reticulum (005783) OR cytoplasm (005737)], except those that also appear in [extracellular 

region part (044421) OR plasma membrane (005886) OR cell surface (009986) OR secretion (046903).” A 

similar approach was used for identification ligands (not shown in the interest of space). Note that receptors 

may also be ligands (e.g., CD28/CD80,86), such that both the “receptor” and the “ligand” list will be applied to 

lymphoid data to identify potential binding partners for stromal receptors. Multiple probesets for individual 

receptors or ligands (where they exist) will be collapsed into a single EntrezGene identifier using the GeneSet 

Enrichment Analysis tool (www.broadinstitute.org/gsea). An automated script will then be used to search 

relevant literature databases for the co-occurrence (co-citation) of every term in the receptor list receptor with 

each term in the ligand/counter-receptor list. Individual publications citing more than 20 total genes (i.e.,

Research Strategy Page 27

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
genomic analyses) will be eliminated, since co-occurrence in such publications is unlikely to be related to 

functional interaction. To increase statistical power, both human and mouse homologs will be searched. 

Since the starting lists are heavily biased towards receptors and ligands, frequent co-occurrence is likely to 

represent cognate receptor:ligand pairs. Note that this second approach (Boolean ontologies and literature 

co-occurrence) will generate a much larger (noisier) list than the first approach, but it has the advantage of an 

integrated scoring (priority) system, in the form of co-occurrence frequency (i.e., high frequencies of cooccurrence are likely to be more biologically important, and also to have existing genetic tools). As will be 

described in Aim 3, co-occurrence score and the availability of genetic model systems, together with other 

parameters, will be used to prioritize the outcomes (which are expected to include a relatively large number of 

potential interactions, based on similar studies we have performed in young wildtype mice). Integration of the 

results of both approaches into a single database, such that the list can be sorted using either approach, or 

both, will minimize the limitations of either approach while retaining the strengths of each. Note that a 

mandatory requirement for the presence of both a receptor (stromal) and its ligand (lymphoid) in the thymus 

will substantially reduce the frequency of false positives, since the probability of a falsely identifying a 

receptor as being expressed in stromal cells AND identifying its ligand as being expressed in lymphoid cells 

is the square of the two probabilities. This is a very significant advantage in discriminating between genes 

found by random chance, and those that are likely to be functional.

AIM 3. PRIORITIZE CANDIDATE LYMPHOID → STROMAL SIGNALS. The studies described in Aims 1 and 2 will 

generate a single, searchable, sortable database of genes expressed by stromal and lymphoid cells during 

lymphoid induced growth, and will identify receptor:ligand pairs among these. As described above, the 

frequency of receptor:ligand co-occurrence can be used to establish a preliminary prioritization scheme, 

where genes that are frequently co-cited are likely to be of relatively high biological importance. In this Aim, 

several additional scoring parameters will be added to strengthen overall priorities. One of the most important 

is the generation of a thymus-specific score. The approach is similar to that for generating a literature cooccurrence score for receptors and ligands, except that in this case, PubMed and PubMed Central databases 

will be searched for the co-occurrence of the receptor or ligand in the context of the thymus (i.e., using the

search terms “thymus” or “thymic” or “thymocyte”). Receptor:ligand pairs that are frequently co-cited with 

each other (high biological importance), but infrequently cited in reference to the thymus (or not at all), will 

represent very high priority candidates. Further, an overall score can also be developed, as defined by 

(receptor:ligand score / thymus score). As another scoring metric, we will also perform ANOVA on the 

dynamic (time course) data for stromal receptor gene expression; gene signals that change the most 

(smallest q value, equivalent to p value corrected for multiple testing) can be prioritized, since these are likely 

to encode receptors that change the most during the kinetic response to lymphoid cells. Again, the ANOVA q

value can be utilized independently for prioritization, or this attribute can be combined with any (or all) of the 

other scores to generate an overall score. The decile in which a receptor signal occurs (i.e., the relative 

signal intensity) may also be used for prioritization; this may be especially important for gene signals that are 

near the median expression value (e.g., 40th to 60th percentile; see Aim 1), since higher confidence can be 

assigned to genes that are more highly expressed.

Although these scoring methods are likely to be sufficient for prioritization of the receptor:ligand results, we 

will implement additional quantitative criteria as well. One particularly powerful approach is represented by 

the STRING (Search Tool for the Retrieval of Interacting Genes and Proteins) database (www.string-db.org). 

This represents a comprehensive database dedicated to identifying and scoring the relevance of 

protein:protein interactions, using informatic and experimental resources. Protein interaction data represented 

by multiple independent resources (MINT, HPRD, BIND, DIP, BioGRID, KEGG, Reactome, IntAct, EcoCyc 

and NCI-Nature) are included in the STRING interaction database. Importantly, STRING can generate scores 

based on multiple types of evidence; most relevant for the present project is STRING’s own version of a 

literature co-citation score, as well as the strength of experimental (as opposed to informatic) evidence. 

Based on these and other scoring criteria, STRING can also generate an overall confidence score that, 

again, can be used independently, or combined with any of the scores described above as a metric for 

prioritization.

In addition to these quantitative metrics, other more qualitative (but nonetheless useful) criteria will be applied 

for final prioritization. For one, automated scripts (already generated) will be used to parse relevant genetic 

resources (Jax Mouse Genome Informatics, NCRR Mouse Mutant Resource Centers, the Knockout Mouse 

Repository, etc.), providing a direct link (hyperlink) from genes in our database to existing genetic models 

(mutant mice, ES cells, or targeting vectors), where they exist. This will allow us to rapidly identify 

receptor:ligand candidates that are amendable to biological testing (Aim 4) within the short timeframe of this 

Research Strategy Page 28

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
project. The same approach can be used to parse reagent databases (Addgene, GeneCards, Abcam) for 

other valuable resources, such as antibodies, siRNAs, expression vectors, etc. A further independent 

approach will be to organize the dynamic stromal receptor data into hierarchical clusters (k means clustering); 

receptors in clusters that (upon visual examination) appear to be characteristic of specific phases of the 

growth process will be flagged in the database as being potentially more interesting than clusters that map to 

multiple phases. For instance, a cluster of genes (receptors) that is specifically upregulated (or 

downregulated) at the “initiation of growth” phase (Fig.2) might be expected to contain receptors play a key 

role in early response to lymphoid signals. Finally, manual evaluation of high-priority candidates in the

receptor:ligand list for those with known relevance in processes such as proliferation, differentiation, or 

survival, especially in cells of epithelial or mesenchymal origin (the primary stromal lineages in the thymus) 

will also be performed. In this respect, it is important to note that high-throughput approaches (such as the 

one described above) generate large numbers of results that are not amenable to manual curation unless 

other criteria can be first applied to help to establish preliminary priorities. Thus, the multi-faceted, redundant, 

and quantitative scoring approaches described earlier are essential in allowing final (qualitative) prioritization 

methods to be applied. The combination of all these approaches will be used to advance a few select 

candidates to Aim 4.

AIM 4. ESTABLISH BIOLOGICAL RELEVANCE FOR ONE OR MORE HIGH-PRIORITY LYMPHOID → STROMAL SIGNALS. 

The goals of the previous Aims are to characterize the stromal gene expression response to lymphoid cells in 

global detail. While this is intellectually interesting, it is also important to establish the biological relevance of 

the predictions made by our approach. The financial resources that can be provided by the R21 mechanism 

are limited. However, for a few select candidates that meet all of the above criteria (stromal receptor, 

lymphoid ligand, high co-occurrence/thymus/overall scores, low ANOVA q value, known biological relevance, 

availability of genetic models, etc.), the path to establishing biological relevance is clear. The two most 

obvious approaches are 1) viable germline mouse mutant alleles (alternatively, conditional mutant alleles) of 

the lymphoid ligand, and 2) viable germline mouse mutant alleles (or conditional mutant alleles) of the stromal 

receptor. In the case of conditional alleles, deletion would be mediated by crossing to hCD2[Cre] (de Boer et 

al., 2003) for lymphoid ligands, or Foxn1[Cre] (Gordon et al., 2007) for stromal epithelial receptors; both 

strains are already in our laboratory. Regardless of the tissue target (lymphoid or stromal, conditional or 

germline), valid candidates would be expected to have a hypocellular thymus. In many respects, a 

lymphoid (ligand or counter-receptor) model system would be preferable, since in this case, transplantation of 

lineage-negative marrow from mutant mice into IL7R-/-

 recipients would be expected to exhibit absence of the 

induced growth response, providing very clearly evidence of the presence of a lymphoid signal for stromal 

cells. Downstream experiments (outside of the context of this application) would include more detailed 

characterization of the stromal response, including an understanding of the type of signal being transmitted 

(proliferation, differentiation, survival). An in-depth description of these is premature at this point, and not

specifically relevant to the current proposal.

In conclusion, we have the technology and the expertise to make a significant impact on the poorly 

understood process of how stromal cells respond to the presence of lymphocytes to shape the 

microenvironment for steady-state lymphopoiesis. We wish to reemphasize that we possess documented 

(published) expertise in all of the relevant methodologies, as well as in interpreting complex outcomes in a 

meaningful fashion. Our commitment to providing the unique data resources generated by these highthroughput approaches to the scientific community at large is also documented. Thus, we believe that the 

proposed studies are important, highly feasible, and will fuel progress and an understanding of the underlying 

process by facilitating the work of many other research groups.

TIMELINE. Most of the first 6-8 months of the project will be spent determining the kinetics of growth in the 

IL7R-/-

 model, and then performing microdissection/cell sorting at the relevant time points. The next 6-8 

months will consist almost exclusively of data analysis and prioritization of the outcomes. The remaining time 

(8-12 months) will be spent refining the outcomes for publication, as well as performing tests of biological 

relevance using existing genetic models, as outlined in Aim 4. Additional information on the timeline is 

included in the Personnel Justification.

Research Strategy Page 29

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
VERTEBRATE ANIMALS

1. Mice: a total of 420 mice are requested for the project. The main experiment described in Aim 1 will involve 

5 time points, each of which will be represented by 3 microarrays, each of which will contain tissue from three 

IL7R-/- mice, for a total of 45 mice. However, only males will be used to minimize variation, so the actual 

number of IL7R-/- mice required is 90. For each of these, one sex-matched wildtype donor (C57BL/6) will be 

required (90 mice). For the preliminary establishment of growth kinetics, there will be 9 time points 

represented by 3 IL7R-/- mice each; again, only males will be used as recipients, and an equal number of sexmatched wildtype donors will be required, so the number of mice required for this experiment is 108. A second 

preliminary experiment to determine more precisely the points corresponding to initiation of growth and peak 

size will require an equal number of mice (108). Note that in some cases, it may be possible to transplant 

multiple IL7R-/- recipients with marrow from a single donor, depending on the availability of recipient and donor 

mice of the proper age at the same time. If this is possible, we will do so, which will reduce the numbers of 

wildtype donor mice required by some proportion. In addition to the above experimental mice, each strain 

(IL7R-/- and C57BL/6) will need to be bred, involving one breeding male and two breeding females for each 

strain, replaced every six months for the duration of the project (24 mice). Some additional mice will be 

required for Aim 4 (biological validation of select high-priority candidates). The number depends on many 

factors, including whether the model strain is a germline or conditional mutant, and whether it is a lymphoid or 

stromal model. An amendment to animal numbers will be filed to reflect the appropriate number, depending on 

these parameters. However, as a preliminary estimate, the number is expected to be small, generally <200 

total mice for these preliminary validation experiments. 

2. Animals must be used because we are examining the function of the thymus as an organ, and there are no 

artificial thymic organs, or any way to recapitulate the function of the thymus in vitro. Numbers of animals were 

justified in section 1. 

3. Veterinary care is provided by Animal Resources Center staff, which carries out a variety of laboratory 

diagnostic procedures and provides oversight for the TSRI rodent preventive health quality assurance 

program. Services are provided either “in-house”, or are referred to outside laboratories as is necessary. 

Necropsy and histopathology can be performed according to investigator needs, from basic or comprehensive 

diagnostic studies to tissue-specific or comprehensive research studies (e.g., preclinical toxicology safety 

studies, mutant mouse phenotype studies). Complementary clinical pathology procedures may be included as 

part of the comprehensive work-ups. Clinical pathology work can also be provided, including: (1) clinical 

hematology, including: complete blood counts, differential white blood cell counts, reticulocyte counts, platelet 

counts, hematocrit; (2) serum biochemistry; (3) parasitology; (4) cytology, (5) microbiology; (6) urinalysis, (7) 

diagnostic serology for specific animal pathogens, (8) molecular biology for specific animal pathogens. 

4. Animals undergoing more than momentary distress (needle stick, etc.) will be anesthetized using standard 

protocols (isoflurane, buprenorphine, ketamine/xylazine). Subsequent to any invasive procedure, animals will 

be monitored until recovery from anesthesia, and at least daily for the first week thereafter, for adverse 

symptoms including hunched posture, loss of hair, weight loss, lethargy, or other symptoms of abnormal 

appearance or behavior. Mice will be treated as recommended by the attending veterinarian, or if more 

appropriate, euthanized to relieve severe discomfort. 

5. Euthanasia will be performed by carbon dioxide asphyxiation followed by thoracotomy. This method is 

consistent with the recommendations of the Panel on Euthanasia of the American Veterinary Medical 

Association. 

Vertebrate Animals Page 30

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
BIBLIOGRAPHY AND REFERENCES

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Balciunaite, G., Ceredig, R., Fehling, H. J., Zuniga-Pflucker, J. C., and Rolink, A. G. (2005). The role of Notch 

and IL-7 signaling in early thymocyte proliferation and differentiation. Eur J Immunol 35, 1292-1300. 

Ben-Shlomo, I., Yu Hsu, S., Rauch, R., Kowalski, H. W., and Hsueh, A. J. (2003). Signaling receptome: a 

genomic and evolutionary perspective of plasma membrane receptors involved in signal transduction. Sci 

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Crompton, T., Outram, S. V., Buckland, J., and Owen, M. J. (1998). Distinct roles of the interleukin-7 receptor 

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de Boer, J., Williams, A., Skavdis, G., Harker, N., Coles, M., Tolaini, M., Norton, T., Williams, K., Roderick, K., 

Potocnik, A. J., and Kioussis, D. (2003). Transgenic mice with hematopoietic and lymphoid specific 

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Fischer, A., Le Deist, F., Hacein-Bey-Abina, S., Andre-Schmutz, I., Basile Gde, S., de Villartay, J. P., and 

Cavazzana-Calvo, M. (2005). Severe combined immunodeficiency. A model disease for molecular 

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Goldschneider, I., Komschlies, K. L., and Greiner, D. L. (1986). Studies of thymocytopoiesis in rats and mice. 

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Gordon, J., Xiao, S., Hughes, B. r., Su, D. M., Navarre, S. P., Condie, B. G., and Manley, N. R. (2007). 

Specific expression of lacZ and cre recombinase in fetal thymic epithelial cells by multiplex gene targeting 

at the Foxn1 locus. BMC Dev Biol 7, 69. 

Griffith, A. V., Fallahi, M., Nakase, H., Gosink, M., Young, B., and Petrie, H. T. (2009). Spatial mapping of 

thymic stromal microenvironments reveals unique features influencing T lymphoid differentiation. Immunity 

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Heng, T. S., Chidgey, A. P., and Boyd, R. L. (2010). Getting back at nature: understanding thymic 

development and overcoming its atrophy. Curr Opin Pharmacol 10, 425-433. PMID: 20483662.

Mohtashami, M., and Zuniga-Pflucker, J. C. (2006). Three-dimensional architecture of the thymus is required 

to maintain delta-like expression necessary for inducing T cell development. J Immunol 176, 730-734. 

Penit, C., Lucas, B., Vasseur, F., Rieker, T., and Boyd, R. L. (1996). Thymic medulla epithelial cells acquire 

specific markers by post-mitotic maturation. Dev Immunol 5, 25-36. 

Peschon, J. J., Morrissey, P. J., Grabstein, K. H., Ramsdell, F. J., Maraskovsky, E., Gliniak, B. C., Park, L. S., 

Ziegler, S. F., Williams, D. E., Ware, C. B., Meyer, J. D., and Davison, B. L. (1994). Early Lymphocyte 

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Porritt, H. E., Gordon, K., and Petrie, H. T. (2003). Kinetics of steady-state differentiation and mapping of 

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Porritt, H. E., Rumfelt, L. L., Tabrizifard, S., Schmitt, T. M., Zuniga-Pflucker, J. C., and Petrie, H. T. (2004). 

Heterogeneity among DN1 prothymocytes reveals multiple progenitors with different capacities to generate 

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Prockop, S. E., and Petrie, H. T. (2004). Regulation of thymus size by competition for stromal niches among 

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References Cited Page 31

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
RESOURCE/DATA SHARING PLAN 

Within the constraints imposed by the Scripps Research Institute (below), all data generated by 

this project will be shared via peer reviewed publications. In addition, the PI or other project 

staff may describe the related findings in public or private lectures (conferences, seminars, etc). 

Scripps policy dictates that if the nature of the final research data necessitates restrictions on 

the access to and use of the data, such restrictions shall be determined at the time such data is 

generated. In addition, any rights and obligations to third parties are consistent with the terms 

and conditions of the NIH award to ensure proper dissemination of final research data. It is 

anticipated that final research data shall be made available no later than the acceptance for 

publication of the main findings from the final dataset. However, TSRI reserves the right to delay 

disclosure of research findings for an additional sixty (60) days in order to allow TSRI to 

exercise its intellectual property rights. The format or presentation of final research data shall be 

determined at the time such data is generated and in accordance with generally accepted 

scientific standards. Final progress reports shall include information detailing the steps towards 

implementation of additional data-sharing plans. If unique genetic (mouse) resources are 

generated by this project, they will be shared as mandated in NOT-OD-04-042. 

Resource Sharing Plan Page 35

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
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 !""""#

Checklist Page 36

Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.
4. * Program Income

If you checked "yes" above (indicating that program income is anticipated), then use the format below to reflect the amount and 

source(s). Otherwise, leave this section blank.

Is program income anticipated during the periods for which the grant support is requested?

*Budget Period *Anticipated Amount ($) *Source(s)

Yes No

5. * Disclosure Permission Statement

If this application does not result in an award, is the Government permitted to disclose the title of your proposed project, and the name, 

address, telephone number and e-mail address of the official signing for the applicant organization, to organizations that may be 

interested in contacting you for further information (e.g., possible collaborations, investment)? 

Yes No

	


 		

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Principal Investigator/Program Director (Last, first, middle): Petrie, Howard, T.