bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bcl11b is a positive regulator of T-lineage specification (85.19)
Authors: Li Long , Rothenberg Ellen V. 
Published: January 2023

Abstract
Hematopoietic stem cells (HSC) commit to the T-lineage by gradually losing developmental plasticity and gaining T cell identity. A recently discovered transcription factor Bcl11b is expected to be a key regulator in this process. It is known Bcl11b is crucial for alpha/beta T cell development and for survival of double positive cells specifically. However, little is known about how Bcl11b works in the very early stages of T cell development. We have cloned cDNA of four transcripts of Bcl11b, and over-expressed these Bcl11b isoforms in fetal liver HSCs. Our data so far has shown that certain Bcl11b isoforms positively regulate T-lineage specification. While full-length Bcl11b and Bcl11b 1-2-4 are growth inhibitory, full-length Bcl11b stimulates emerging of Thy1+ cells from HSCs under a condition that does not normaly favor T cell development. In another experiment, fetal liver HSCs transduced with Bcl11b 1-3-4 and 1-4 were co-cultured with OP9-DL1 cells or OP9 control cells. The data showed that after 4 days of co-culturing HSCs with OP9 control cells, empty vector infected HSCs showed no developmental progression: almost all cells were c-kit+ CD25-; however, some Bcl11b transfected cells became c-kit+, Thy1+ and CD25+ DN2-like cells, normally seen only on OP9-DL1 cells. Our data revealed that certain isoforms of Bcl11b may stimulate T cell development and may even have a novel relationship to Notch signaling.
Foxn1 is required to maintain Notch ligand expression on TECs (86.11)
Authors: Xiao Shiyun , Manley Nancy 
Published: January 2023

Abstract
Thymic epithelial cells (TECs) are required to promote T cell development inside the thymus. We recently generated a novel Foxn1lacZ allele, in which Foxn1 expression is reduced below 50% of normal at about 7 days postnatal, resulting in rapid thymic degeneration. Using this allele, we showed that Foxn1 is required to maintain TEC function and T cell production in the postnatal thymus. Reduced Foxn1 results in reduced TEC proliferation and MHCIIhi TEC numbers. Total T cell and CD4 SP cells were also reduced, but CD4-8- DN cells were significantly increased. Compared to control mice, we found that the percent of CD44+25- DN1 cells gradually increased from day 14, reaching a peak of 60-80% of all DN cells at day 28. These DN1 cells were predominantly CD19+HSAhi immature B cells, which first increased between day 9 and 12. The ratio of B cells to total thymocytes was 20 fold higher at day 28 in Foxn1lacZ thymus compared to controls, and B cell number also increased. Kithi DN1a and DN1b cells, which have been identified as the progenitors of TCRαβ T cells, were significantly reduced starting at day 9. The ratio of DN1a/b cells to total thymocytes was 15 fold lower at day 9 in Foxn1lacZ thymus than in control thymus. A significant reduction of DN1a/b subsets also appeared in control mice at about 2 months, associated with a significant reduction of total T cell number and down-regulation of Foxn1 expression in TEC. Further, we show that the mRNA level of Notch ligands Dll1 and Dll4 were down regulated in Foxn1lacZ TSCs. These results suggest that Foxn1 may be required to maintain Notch ligand expression in TECs; therefore, down regulation of Foxn1 expression in Foxn1 lacZ mice changes the thymic environment to be favorable to produce B cells instead of T cells.
Tbx1 antagonizes thymus organogenesis (86.4)
Authors: Cardenas Kim T. , Liu Zhijie , Laurent Micheline , Carter Carla , Manley Nancy , Richie Ellen 
Published: January 2023

Abstract
The thymus and parathyroids originate from organ-specific domains in endoderm of the 3rd pharyngeal pouch (PP), identified by Foxn1 and Gcm2 expression respectively at embryonic day 11 (E11). The molecular mechanisms regulating fate determination in the 3rd PP are not clear. Our studies show that neural crest cells (NCCs) play a role in this process (Griffin et al, in press). We also showed that lack of Sonic hedgehog (Shh) results in absence of the parathyroid domain and expansion of the thymus domain (Moore-Scott et al, 2005). It has been proposed that the Tbx1 transcription factor is also required for thymus development and is regulated by Shh. However, Tbx1 is expressed in the Gcm2, but not the Foxn1 domain of 3rd PP at E10.5.
We propose a model of thymus organogenesis in which 3rd PP endoderm assumes a thymus fate unless Shh plus NCC-derived signals specify a parathyroid fate. We further propose that Tbx1 is required to establish parathyroid fate and is non-permissive for thymus fate. To test the model, we generated knock-in mice containing a Cre-inducible allele that allows temporal and spatial control of Tbx1 expression. Ectopic Tbx1 expression using Foxn1Cre resulted in markedly hypoplastic thymi, supporting the notion that Tbx1 antagonizes thymus differentiation. Current studies focus on determining the molecular basis for this phenotype and testing the effects of activating Tbx1 expression at earlier stages. Supported by NIH HD056315 to ER and HD035920 to NM.
Forced-expression of Foxn1 in stromal cells maintains thymic architecture and thymopoiesis in aged mice (86.5)
Authors: Zook Erin C , Zhang Shubin , Witte Pamela L , Le Phong T 
Published: January 2023

Abstract
The thymus is the primary site for thymopoiesis and production of naïve T cells; however, thymic function declines with age. Thymopoiesis requires continuous thymic seeding by early T cell progenitors (ETP), a progeny of the bone marrow-derived lineage marker negative, Sca1pos, c-kitpos (LSK) progenitors that express Flt3 (LSK Flt3pos). A decrease in the frequency of ETP, and in the number of LSK Flt3pos with age has been implicated as a mechanism for the decline in thymopoiesis. We have shown that a decrease in thymocyte numbers occurs as early as 3m of age and correlates with a decrease in Foxn1 expression; however, a role for Foxn1 in thymopoiesis remains unknown. Here, we show that thymi of aged Foxn1 transgenic mice (Tg) have a higher number of thymocytes and ETP compared to aged wild type mice. Forced expression of Foxn1 also rescues aged-associated alterations of thymic architecture. Unexpectedly, we found that Foxn1 is over expressed in the bone marrow (BM). While the LSK and LSK Flt3pos are reduced in aged wild type mice, these populations remain unchanged in aged Foxn1Tg. Furthermore, the aged Foxn1 Tg also have a higher number of the lineage marker negative CD90.2pos CD2pos, a population absent in the Foxn1 mutated nude mice. Thus, our data suggest that expression of Foxn1 is critical for functional thymic and BM stromal cell niches required for the survival of T cell progenitors (NIA AG023809).
Haploinsufficiency of Flt3-ligand limits RAG1 locus activation (87.2)
Authors: Dolence Joseph J , Gwin Kimberly , Medina Kay L 
Published: January 2023

Abstract
Evidence is accumulating that the molecular circuitry initiating lymphoid lineage specification correlates with expression of the receptor tyrosine kinase Flt3. Recombination activating gene-1 (RAG1) locus activation is a hallmark of lymphoid lineage specification. Previous studies established that expression of a RAG1-GFP/+ reporter begins in a subset of lineage negative (Lin-) cells that express high levels of c-kit and Sca-1 (LSK+). To investigate a regulatory connection between Flt3 signaling and RAG1 locus activation from this stage, RAG1-GFP/+ knockin mice expressing wildtype, heterozygote, and knockout Flt3-ligand (FL) alleles were generated. Mono-allelic expression of the FL gene reduced FL transcripts by half, providing an in vivo model to evaluate threshold requirements for FL in lymphocyte development. Percentages and numbers of LSK+ cells were similar in FL+/+ and FL+/- mice, but significantly decreased in FL-/- animals. Analysis of GFP expression within the LSK+ compartment revealed a FL dose dependent reduction in frequencies and numbers of GFP+ cells. The requirement for threshold levels of FL in regulation of GFP expression extended into the B220- c-kitlo IL-7R+ lymphoid progenitor and CD43+ B220+ Pro-B compartments, but not in later stage B cell precursors. These findings establish a critical requirement for FL in regulating one event in lymphoid specification, RAG1 locus activation.
These studies were supported by startup funds to K.L.M. from Mayo Clinic.
A comparison of “steady-state” and “emergency” granulopoiesis: evidence of a single pathway for neutrophil production (87.5)
Authors: Cain Derek W , Ueda Yoshihiro , Holl Thomas Matt , Snowden Pilar B , Kondo Motonari , Kelsoe Garnett 
Published: January 2023

Abstract
Normally, neutrophil pools are maintained by steady-state granulopoiesis in bone marrow (BM). Inflammation, however, elicits neutrophilias that outstrip the capacity of steady-state granulopoiesis, and are thought to rely on a distinct program of accelerated production known as "emergency" granulopoiesis. In mice immunized with alum adjuvant, IL-1RI expression by radioresistant cells is required for both the mobilization of neutrophils from BM and increased proliferation by hematopoietic progenitors. Thus, an IL-1RI dependent trans-acting factor(s) mediates the accelerated neutrophil output needed for alum-induced neutrophilias, consistent with models of emergency granulopoiesis where inflammation elicits growth factors, i.e., G-CSF, GM-CSF, IL-3, and IL-6. These models do not, however, explain the emergency-like responses that follow non-inflammatory neutrophil depletion. Similarly, progenitor compartments are constitutively expanded in mice rendered neutropenic by the conditional loss of Mcl-1. Our observations suggest that neutrophilias elicited by inflammation are not the result of a distinct pathway of granulopoiesis, but represent the stabilizing effects of feedback that correct for the loss of BM neutrophils. We propose that inflammatory signals decrease the number of BM neutrophils via mobilization to increase progenitor proliferation through a homeostatic mechanism.
Research support: NIH grants AI24335 and AI56363 (to G.K.)
Estrogen receptor expression promotes the differentiation and activation of splenic dendritic cells and macrophages during inflammation in vivo (87.6)
Authors: Agrawal Hemant , Carreras Esther , Bajana Sandra , Kovats Susan 
Published: January 2023

Abstract
De novo differentiation of inflammatory dendritic cells (DC) and macrophages (MΦ) occurs in autoimmune diseases that are strongly female biased in incidence. We previously showed that estrogen receptor alpha (ERα) signaling promotes DC differentiation mediated by GM-CSF, an inflammatory pathway. To compare the efficiency of myeloid cell differentiation from ERα+ and ERα-/- bone marrow (BM) cells in vivo, we generated mixed competitive ERα+/ERα-/- BM chimeric mice. In the radiation-induced inflammatory environment 3 weeks post reconstitution, DC and MΦ in spleen and BM were derived preferentially from ERα+ BM cells, and ERα+ DC displayed higher levels of CD86. These data show that during inflammation ERα signaling promotes the new differentiation and activation of myeloid cells. In contrast, in the homeostatic environment 3 months post reconstitution, DC, MΦ and lymphocytes were predominantly derived from ERα-/- BM cells, consistent with reports that ectopic estradiol depletes hematopoietic progenitors. In chimeric mice, ER signaling also increased splenic DC activation induced by in vivo exposure to TLR9 ligands: ERα+ cDC displayed significantly more CD86 than ERα-/- DC. Thus, during inflammation in vivo, ERα signaling in response to physiological levels of endogenous estrogens promotes DC and MΦ development and activation. Supported by OCAST HR06-157 & NIH AI079616, RR020143.
Unexpected expression of peptidoglycan recognition protein 2 in lymphocytes and bone marrow hematopoietic stem cells (87.8)
Authors: Wang Zhien , Xu Min , Locksley Richard M 
Published: January 2023

Abstract
Peptidoglycan recognition factors are highly conserved molecules involved in recognition of fragments of bacterial peptidoglycans in innate immune responses. Peptidoglycan recognition protein 2 (PGLYRP2) is a serum N-acetylmuramoyl-alanine amidase secreted by the liver. We used a green fluorescent reporter allele engineered into the gene to label cells in the mouse that endogenously express PGLYRP2. Unexpectedly, PGLYRP2 was expressed constitutively in resting CD4 and CD8 lymphocytes and in NK cells. Reconstitution of PGLYRP2-deficient mice with PGRLYRP2-sufficient T cells led to the accumulation of PGLYRP2 in serum. In assessing bone marrow populations in these mice, we identified constitutive PGLYRP2 expression in a subset of lineage-negative, c-kit+Sca1+ cells that had the properties of hemopoietic stem cells, including the capacity to establish hematopoietic lineages and for self renewal when transferred into irradiate recipient mice. Expression of PGLYRP2 was also confirmed within the conventionally identified hematopoietic stem cell compartment in wildtype mice, confirming the unexpected expression of this enzyme in bone marrow stem cells.
CM1 ligation induces the apoptosis of cervical cancer Hela 229 cells via Fas/FasL interaction (88.11)
Authors: Hur Dae Young , Park Ga-Bin , Kim Yeong-Seok , Song Hyunkeun , Sung Minjung , Lee Hyun-Kyung , Lee Wang Jae 
Published: January 2023

Abstract
CM1(centrocyte/-blast marker I) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on a subpopulation of centroblasts and centrocytes of human germinal center(GC) B cells. Interestingly cisplatin or PMA induced CM1 expression on cervical cancer cell (Hela 229). In addition, we observed the existence of CM1 in cervical cancer patients' tissues. In this study, we observed the function of CM1 induced by cisplatin on cervical cancer cells. So we designed to investigate the enhancement of the chemoresponse to cisplatin by anti-CM1 mAb treatment in human cervical cancer Hela 229 cells. We observed that CM1 ligation with anti-CM1 mAb enhanced the apoptosis of Hela cells pre-treated with cisplatin and induced the expression of both FasL and Fas in theses cells. Furthermore, anti-Fas blocking antibody, ZB4, blocked CM1-mediated apoptosis effectively in Hela cells. Caspase-8 inhibitor, z-IETD effectively blocked CM1-induced cell death. And CM1 ligation down-regulated expression of procaspase-8 and PARP. RT-PCR results showed up-regulated the expression of Bax and Bad and down-regulated the expression of Bcl-2. The release of cytochrome c and the translocation to nucleus of endoG and AIF were showed by confocal micoscopy. Based on these findings, it can be concluded that CM1 might act as an effective apoptosis inducer in chemotherapy of cervical cancer by regulating the expression of various apoptosis-related genes via Fas/FasL pathway.
Tumor Associated Ascites Inhibits CD1d-Mediated NKT cell Activation (88.18)
Authors: Webb Tonya J , Rogers Ophelia , Giuntoli, II Robert L , Schneck Jonathan P , Oelke Mathias 
Published: January 2023

Abstract
Natural killer T (NKT) cells recognize lipid antigen presented by CD1d molecules. It has been shown that NKT cells can both directly and indirectly mediate anti-tumor immunity. However, it is thought that the anti-tumor effects mediated by these cells are being hampered because the number and function of NKT cells are reduced in cancer patients. In addition, it has been shown that tumor associated glycolipids are frequently shed into the tumor microenvironment, which can mediate immunosuppressive activity. In these studies we examined antigen presentation by CD1d following treatment with ascites from ovarian cancer patients. It was found that pretreatment with ascites inhibited the ability of CD1d expressing cells to activate NKT cells in a dose-dependent manner. We found that this inhibition does not require antigen processing, as canonical (Vα14+) and noncanonical NKT cells, which do not require trafficking through endocytic compartments, were both inhibited. Also, ascites treatment of artificial Antigen Presenting Cells (aAPC) preloaded with α-GalCer, abrogated their ability to present antigen to NKT cells, which further suggests that the inhibition is antigen processing independent. In addition, our data demonstrate that treatment antigen presenting cells with ascites does not inhibit activation of classical CD8+ T cells. Together, these data suggest that glycolipid shedding in ascites may be a mechanism of immune evasion specifically utilized used by cancers to inhibit CD1d- mediated activation of NKT cells.
New biomolecules for cancer therapy (88.2)
Authors: Campigna Emmanuelle , Morisseau Sebastien , Garambois Veronique , Germain Claire , Larbouret Christel , Mach Jean-Pierre , Pèlegrin André 
Published: January 2023

Abstract
It has been previously demonstrated that tumor cells expressing MICA are no more able to grow in vivo due to the killing of tumor cells by both NK and CD8+ T cells.
In order to restore the presence of the MICA ligand at the surface of tumor cells, we designed biomolecules composed of MICA and an scFv (single chain fragment variable) that can recognise tumor associated antigens (TAA). The biomolecules should target tumor cells and re-direct the specific lysis of tumor cells by NK cells after interaction between NKG2D and exogenous MICA at the surface of tumor cells.
In vitro cytometry experiments showed that the biomolecules specifically bind different tumor cells expressing TAA. Using 51Cr release assay, we demonstrated that the biomolecules induce an efficient and specific killing of tumor cells mediated by NK cells or human PMBCs. In vivo, biodistribution studies showed that the biomolecules could target xenografted tumor when injected intravenously. Consequently, a protocol is investigated for therapy.
MicroRNAs regulate NKG2D ligands on tumor cells (88.21)
Authors: Yadav Deepak , Ngolab Jennifer , Lim Rod S , Krishnamurthy Siddharth , Bui Jack D 
Published: January 2023

Abstract
NKG2D is a receptor used by NK cells to detect virally infected and transformed cells. It recognizes ligands that are expressed constitutively on primary tumors and tumor cell lines. We have identified four microRNAs (miRNAs) that each was sufficient to reduce the expression of the NKG2D ligand MHC class I-related chain A (MICA). These include miR-106b, -302b, -372, and -520b. Interestingly, mir-372 was also found to reduce the expression of another NKG2D ligand, UL-16 binding protein 2 (ULBP2). One of these miRNAs (miR-520b) was induced by IFN-gamma, leading to a reduction in MICA surface protein levels. miR-520b acted on both the MICA 3'-untranslated region and the promoter region and caused a decrease in the levels of MICA transcript. In contrast, an antisense oligonucleotide inhibitor of miR-520b increased the expression of a reporter construct containing the MICA 3'-untranslated region but not the MICA promoter region. These findings demonstrate the novel regulation of NKG2D ligands by endogenous microRNAs.
B cells are required for T cell activation during tumor immunity (88.27)
Authors: DiLillo David J. , Tedder Thomas F. 
Published: January 2023

Abstract
T cells are considered the major contributors to tumor immunity. Because B cells can regulate T cell-mediated immune responses, the role of B cells in tumor immunity was assessed. B cells were depleted in mice with otherwise intact immune systems using CD20-specific mAbs before tumor administration. Subcutaneous B16 melanoma tumors grew to be twice as large in mice lacking B cells compared to control mice. Similarly, the number of visible melanoma metastasis foci on the surface of the lungs was doubled in B cell deficient mice. The numbers of CD4+ and CD8+ effector-memory T cells generated during the anti-tumor response were reduced by 48% and 33%, respectively, in the draining lymph nodes of B cell deficient mice compared to control mice. The induction of IFNγ-secreting CD4+ and CD8+ T cells was impaired by 42% and 34%, respectively, in mice that lacked B cells. Likewise, the induction of TNFα-secreting CD4+ and CD8+ T cells was impaired by 47% and 50%, respectively, in B cell deficient mice. Finally, the proliferation of adoptively-transferred tumor antigen-specific T cells was reduced by 30% in mice lacking B cells. Thereby, tumor growth and metastasis were dramatically enhanced in B cell deficient mice due to a significant reduction of the tumor-specific T cell response. Thus, B cells are required for optimal T cell activation during tumor immunity.
Supported by NIH Funding (CA105001 and AI056363)
Anti-MUC1 antibody responses in endometriosis and ovarian cancer in humans and preclinical MUC1 transgenic models (88.29)
Authors: Budiu Raluca Andreia , Edwards Robert P , Vlad Anda M 
Published: January 2023

Abstract
Ovarian cancer is the deadliest gynecologic malignancy and endometriosis is the only currently described precursor lesion. MUC1 mucin is an ovarian epithelial tumor-associated antigen and a vaccine candidate for ovarian cancer immunotherapy. Natural and vaccine-induced MUC1 immunity, often studied in ovarian cancer is much less understood in endometriosis. Human and murine mucin 1 share little homology in the extracellular region and transgenic mouse models expressing the human antigen are needed. We generated two novel preclinical models for MUC1 positive endometriosis and MUC1-expressing ovarian tumors, respectively. The MUC1KrasG12D mice develop MUC1-positive ovarian endometriosis after AdCre injection under the ovarian bursa. MUC1KrasG12D transgenic mice injected with MUC1-expressing immortalized ovarian surface epithelial cells (OSE) develop tumors throughout the peritoneal cavity and serve as a transplantable in vivo tumor model. Our results show that MUC1 is immunogenic in humans and mice with either malignant or premalignant lesions and triggers MUC1-specific IgM and Th2-driven IgG antibodies. Furthermore, the presence of IgG in cancer patients correlates inversely with survival. In additions, mice and humans show several differences in immune regulation by other CD4 T cell subsets (Th17, Treg) with consequences for MUC1 vaccination in preclinical models. PA Dept of Health, CMRF.
ADAM33 regulates IL-18-secreted process in gastric cancer cells (88.4)
Authors: Kim Kyung-Eun , Cho Dae-Ho 
Published: January 2023

Abstract
Interleukin (IL)-18 has recently been reported to play a critical role in tumor migration, invasion, and metastasis. Because IL-18 has various biological activities after its secretion as an 18 kDa mature form, the regulation of IL-18-secretion process is an important step in tumor progression. This study investigated the implication of IL-18 in vascular endothelial growth factor (VEGF)-D-regulated migration, along with the role of IL-18-secretion process. VEGF-D enhanced cell migration, which was then blocked by inhibiting IL-18. VEGF-D increased IL-18 expression and secretion, suggesting that IL-18 is a critical mediator for VEGF-D-enhanced migration. VEGF-D induced a disintegrin and metalloprotease 33 (ADAM33) expression, which has a metalloproteinase domain. VEGF-D-enhanced IL-18 secretion and cell migration were inhibited by ADAM33 knock-down. Moreover, cell proliferation was considerably reduced in ADAM33 siRNA transfectants. In conclusion, ADAM33 has a key role in gastric cancer pathogenesis by up-regulating IL-18 secretion process, resulting in increased cell migration and proliferation.