bluuebunny/crossref_metadata_2025_split huggingface dataset:
Signature Gene Expression Patterns Revealed in Hypoplastic Thymii from Mouse Models of DiGeorge-22q11.2 Deletion Syndrome
Authors: van Oers Nicolai S , Du Qiumei , de la Morena M Teresa , Dozmorov Igor , Khan Shaheen , Cleaver Ondine B 
Published: January 2023

Abstract
Chromosome 22q11.2 deletion syndrome (22q11.2 ΔS) is the most common microdeletion disorder reported (1/4000). Individuals with this deletion have variable, multi-system disorders including thymic hypoplasia, cardiac anomalies, hypoparathyroidism, and/or dysmorphic facial features. Over 90% of patients have a deletion of 2.4 Mb, which comprises 90 genes, 50% protein coding and the remainder microRNAs, long noncoding RNAs and pseudogenes. The principal cause of the development defects is a haploinsufficiency of the T-box 1 transcription factor (Tbx1). Between 40–60% of patients have some degree of thymic hypoplasia, resulting in systemic T cell lymphopenia. Defects in the thymic stromal tissue is the underlying cause of the hypoplasia. We analyzed the thymic tissue in the mouse models of 22q11.2 ΔS (Df1/+). Comparative transcriptome analyses of hypoplastic and normal-sized lobes derived from the same Df1/+ embryo revealed a signature mRNA expression pattern unique to hypoplastic lobes. Ingenuity pathway analysis uncovered selective pathways compromised in the hypoplastic lobes. Fetal thymic organ culture and reaggregate cultures are currently being used to identify the genes essential for the specification and expansion of the thymic stroma. In addition, normal and hypoplastic thymii, including some from 22q11.2 ΔS patients, are being characterized for the expression of the over- and under-represented genes identified in the mouse model. Findings from these studies may lead to better strategies for improving human thymopoiesis in patients with conditions including 22q11.2 and 10p syndromes, those undergoing chemoablative treatments, and other conditions leading to a thymic hypoplasia and ensuing T cell lymphopenia.
A delicate balance of PI3K activation is required for CD8 T cell survival and generation of memory cells
Authors: Cannons Jennifer Leigh , Kapnick Senta , Preite Silvia , Gomez-Rodriguez Julio , Reilley Julie , Handon Robin , Wu Tuoqi , Uzel Gulbu , Schwartzberg Pamela L 
Published: January 2023

Abstract
The p110d subunit of phosphatidylinositol-3-OH kinase (PI(3)K) is selectively expressed in leukocytes and is critical for lymphocyte biology. We previously reported patients heterozygous for three different germline, gain-of-function mutations in PIK3CD (encoding p110d). Patients presented with sinopulmonary infections, lymphadenopathy, nodular lymphoid hyperplasia and CMV and/or EBV viremia, suggestive of immune dysfunction. We established a mouse model (PIK3cd E1024K) that recapitulates features of this disease including lymphopenia, yet enlarged secondary lymphoid organs, as well as increased Akt phosphorylation and hyperactivation of the metabolic checkpoint kinase mTOR. In response to TCR stimulation, mutant T cells proliferate, but rapidly die via a Fas/FasL-mediated apoptosis. The few surviving mutant CD8 T cells exhibit features of short-lived effectors, expressing abundant cytokines and elevated granzymes, and kill target cells more efficiently than WT counterparts. This phenotype is mirrored at early time points following viral infection. However, at late time-points post-viral infection, mutant CD8 T cells fail to sustain expression of proteins critical for maintenance of long-lived memory cells. Thus, our data suggests that activated p110d limits effective CD8 T cell memory. Our mouse model therefore recapitulates facets of the human primary immunodeficiency, revealing insight into the pathogenesis of this disease.
Patients with Compound Heterozygous Mutations in Forkhead Box N1 have a Severe Immunodeficiency while Maintaining Normal Skin and Hair Development
Authors: van Oers Nicolai S , Khan Shaheen , Padron Grace T , Du Qiumei , Dozmorov Igor , Markert M. Louise , de la Morena M Teresa 
Published: January 2023

Abstract
Forkhead Box N1 (FoxN1) is an epithelial-specific transcription factor essential for the development of the thymus. Patients with mutations in Foxn1 (OMIM # 600838) are born with a severe T-cell lymphopenia that presents in combination with alopecia and nail dystrophy. The nude mouse, which developed from a spontaneous genetic mutation in Foxn1, phenocopies the human disease. We report on 3 independently identified patients that presented with low to absent circulating T cells. Genetic workup of these patients revealed mutations in Foxn1. Each patient had distinct compound heterozygous mutations that were localized in the distal exons of Foxn1. These were predicted to maintain Foxn1 expression while adversely affect its function. Of significance, each patient had normal hair and skin, without any evidence of nail dystrophy, distinct from previously reported phenotypes. To better define the molecular mechanisms leading to this novel clinical presentation, we used CRISPR/Cas techniques to introduce the corresponding mutations in the mouse Foxn1 sequence. We will present data on the phenotypes of these mice, using intercrosses between individual mutant mice. Comparative transcriptome analyses of fetal thymii from these mice will reveal how the Foxn1 mutations impacts thymic epithelial gene expression and function compared to normal Foxn1. Our findings may lead to better understanding of the role of Foxn1 epithelial cell development and function in both the thymus and skin.
A Novel Mendelian Disease of Autoimmunity caused by Mutations in a small GTPase
Authors: Leney-Greene Michael Alexander , Park Ann , Chao Brittany , Schwefel David , Balasubramaniyam Arasu , Ozen Ahmet , Vilarinho Silvia , Morawski Aaron , Daumke Oliver , Su Helen , Lenardo Michael J 
Published: January 2023

Abstract
In this study, we harness Whole Exome Sequencing (WES) to interrogate the underlying genetic cause in a patient cohort suffering from a Mendelian disease of immune dysregulation characterized by severe lymphopenia, splenomegaly, anemia, thrombocytopenia and liver failure. Bioinformatic analysis revealed novel mutations in a small GTPase that led to a near complete loss of mature protein in patient cells. Animal models lacking these genes develop a disease remarkably similar to that observed in the human patients, however, the molecular role of this GTPase in the immune system remains a fundamental gap in our knowledge. Due to a remarkable similarity in phenotypes between mice deficient for this small GTPase and T cell specific deletions of regulators of mTORC1, we hypothesized that this gene may be involved in the mTORC1 signaling pathway. We observe a robust association between this GTPase and members of the ragulator complex which is required for recruitment of mTORC1 to the lysosome and subsequent signalling. Furthermore, in human T cells deficient for this GTPase we observe increased phosphorylation of targets downstream of mTORC1. Overall, our data suggest that this GTPase is a novel T cell specific negative regulator of mTORC1 signalling.
This research was supported by the Intramural Research Program of NIAID, NIH.
EBI2 contributes to central tolerance by promoting rapid motility of medullary thymocytes
Authors: Thyagarajan Hiran Maye , Ki Sanghee , Hu Zicheng , Lancaster Jessica , Ehrlich Lauren 
Published: January 2023

Abstract
Maturing thymocytes enter the thymic medulla, where they encounter numerous self-antigens presented by antigen presenting cells (APC). Those thymocytes that are strongly self-reactive undergo either negative selection or diversion into the regulatory T cell lineage. Although the majority of the proteome is expressed in the medulla, many self-antigens are expressed by only a minor fraction of medullary APC; thus, thymocytes must efficiently enter the medulla and scan APC to ensure central tolerance. Chemokine receptors promote lymphocyte migration, organization within tissues, and interactions with APC in lymphoid organs. The chemokine receptor EBI2 governs the localization of T cells, B cells, and dendritic cells (DC) during immune responses in secondary lymphoid organs. However, the role of EBI2 in thymocyte development has not been elucidated. Here, we demonstrate that EBI2 is expressed by murine CD4+ single positive (CD4SP) thymocytes and thymic DC. EBI2 deficiency did not impact thymocyte cellularity or subset distribution, but did alter the TCR repertoire. Furthermore, EBI2 deficiency impaired negative selection of OT-II TCR transgenic thymocytes responding to an endogenous self-antigen. Two-photon imaging revealed that EBI2 deficiency resulted in reduced migration and impaired medullary accumulation of CD4SP thymocytes. These data identify a role for EBI2 in promoting efficient central tolerance.
Deletion of the Dense Core Vesicle Proteins IA-2 and IA-2β Causes Profound Leukopenia in Mice
Authors: Gunti Sreenivasulu , Gottumukkala Raju VSRK , Carmona Gilberto N , Notkins Abner Louis 
Published: January 2023

Abstract
Previous studies showed that deletion of the genes encoding the dense core vesicle (DCV)-associated proteins IA-2 and/or IA-2β resulted in a decrease in the secretion of a number of hormones and neurotransmitters and that this, in turn, led to a variety of pathophysiologic and behavioral abnormalities. The effect of the deletion of these genes on the immune system has never been studied. In the present experiments, we found that the knockout of the IA-2 and IA-2β genes (double knockout) resulted in a profound leukopenia characterized by a 78% decrease in WBCs and an 84% decrease in absolute number of lymphocytes. The leukopenia was detected within 1.5 months after birth and persisted for at least 12 months. Both B and T cells were decreased by about 40–50% in bone marrow and thymus and by about 75% in the spleen. LPS-induced cytokine secretion (e.g., IL-6, MCP-1, INF-γ and TNF-α) also was severely impaired. The most likely explanation for these profound immunological abnormalities in single and double knockout mice is that they represent secondary events resulting from impaired secretion of hormones and neurotransmitters that are involved in immunological homeostasis.
On the mechanism of leukocytosis in patient WHIM-09, cured of WHIM syndrome by chromothripsis
Authors: Liu Qian , Li Zhanzhuo , Yang Alexander , Velez Daniel , Stregevsky Elina , Cho Elena , Holmes Kevin , McDermott David H. , Murphy Philip M. 
Published: January 2023

Abstract
Patient WHIM-09 was cured of WHIM syndrome, an autosomal dominant immunodeficiency disorder caused by gain-of-function CXCR4 mutations, by chromothripsis (chromosome shattering) in a single hematopoietic stem cell (HSC). Chromothripsis fortuitously deleted CXCR4WHIM, and one copy of 163 other genes, resulting in hematopoietic chimerism (100% chromothriptic myeloid cells and 100% WHIM lymphoid cells) and overcorrection of leukopenia in neutrophil and monocyte, but not lymphocyte, lineages to levels stably ~2-fold above normal. Earlier, splenectomy had increased the absolute lymphocyte count stably by ~2-fold. To address leukocytosis mechanisms, we analyzed animal models and patient samples. The total WBC count was increased by splenectomy in wild-type mice, and by Cxcr4 haploinsufficiency in sham or splenectomized mice, due to increases in lymphocytes and monocytes, not neutrophils. Cxcr4 haploinsufficiency also increased mouse bone marrow LSK cell proliferation and reduced neutrophil homing from blood to bone marrow. In the patient, the frequency, absolute number and myeloid colony-forming capacity of blood CD34+ cells were normal; however, bone marrow GMPs generated increased G/M/GM-CFU colonies in vitro. WHIM-09 serum contained increased levels of Groa, MIP-1d, MIG, IL-8 and IL-15, and decreased levels of CXCR4’s ligand SDF-1, which may regulate leukocyte levels. Thus, in WHIM-09 splenectomy and CXCR4 haploinsufficiency may have contributed to monocytosis; whereas HSC hyperproliferation, enhanced differentiation capacity of GMPs, impaired neutrophil homing to bone marrow and skewed serum cytokine levels may all contribute to aspects of leukocytosis.
The Disappearance of Agglutinin from the Blood of Anaphylactic and Normal Animals
Authors: Hempl Hilda 
Published: January 2023

Abstract
In order to throw light on the question of the origin of “anaphylatoxin,” Doerr and Pick (Centralbl., 62, Orig., p 146) and Römer and Viereck (Zeitschrift f. Immunitätsforsch., Orig., Bd. xxi, p. 32) measured the disappeaance of antibodies in heterologous sera in anaphylactic animals.
Doerr and Pick injected a rabbit sensitized to horse serum and a normal rabbit intravenously with cholera agglutinating horse serum, and they found that the amount of agglutinin and of the precipitable horse albumen remained the same in both for about a day and then disappeared faster from the anaphylactic animal than from the other. They injected guinea pigs sensitized to horse serum intraperitoneally with 1 to 2 cc. of cholera agglutinin from the horse and found that the agglutinin and the precipitable horse albumen appeared in the circulation of the sensitized animals more quickly than in that of the others and, up to six hours after injection, they were present in greater quantity.
The Bacteriolytic Power of Normal and Immune Rabbit Serum for Typhoid Bacilli and the Influence of the Intravenous Injection of Vaccine Upon the Same
Authors: Teague Oscar , McWilliams Helen I. 
Published: January 2023

Summary
The work of Buxton and others showing that normal rabbit serum is capable of killing large numbers of typhoid and paratyphoid bacilli and that the sera of rabbits highly immunized against typhoid and paratyphoid bacilli do not kill these organisms is confirmed; it is emphasized, therefore, that the titer of an immune serum as determined by the usual dilution method with the addition of complement is not an indication of the bactericidal power of the blood plasma in vivo.
The bacteriolytic power of normal and highly immune antityphoid rabbit serum for typhoid bacilli is neither increased nor decreased by the intravenous injection of a large dose of typhoid bacilli; the serum of a rabbit that has received only one or two immunizing injections shows a distinct, but not a great, increase in its bactericidal power at five and twenty-four hour intervals after such an injection.
ST8Sia6 attenuates diabetes progression and severity
Authors: Belmonte Paul , Chung Ji Young , Arocha Sinibaldo Romero , Schwab Aaron , Shapiro Michael J. , Fife Brian T. , Shapiro Virginia 
Published: January 2023

Abstract
Nearly 1.25 million Americans suffer from type 1 diabetes, an autoimmune disease which destroys insulin-producing beta cells of the pancreatic islets. Although insulin therapy is a lifesaving treatment, it is not a cure and secondary complications remain a significant concern. Experimental islet transplantation as a curative measure has yet to overcome the barrier of immune-mediated destruction, as patients eventually revert back to insulin-dependency. Immunotherapies to date have focused on targeting the adaptive immune response, largely ignoring the innate immune system, and have had limited success. Siglec-E is an inhibitory receptor expressed on innate immune cells such as macrophages and dendritic cells; it is known to dampen inflammation through several mechanisms. Here, we demonstrate that the sialic acid transferase ST8Sia6, which catalyzes addition of a2,8-linked disialic acids to glycoproteins, produces cell surface ligands for Siglec-E. We selectively expressed ST8Sia6 in pancreatic beta cells, hypothesizing this would have a beneficial effect in delaying disease in the murine multiple low-dose streptozocin model of diabetes. We observe that when diabetes is induced, mice that express ST8Sia6 in beta cells have delayed onset of diabetes and less severe hyperglycemia as compared to littermate controls. Notably, expression of ST8Sia6 in beta cells does not interfere with normal glucose response. Therefore, ST8Sia6 expression in pancreatic beta cells is safe and attenuates diabetes progression and severity. Because cell surface glycans play a major role in recognition of self, this work has significance in islet-targeted gene therapy, transplantation, and graft survival.
The transcription factor NFAT5 inhibits experimental autoimmune encephalomyelitis (EAE) in mice
Authors: Packialakshmi Balamurugan , Hira Sharanpreet , Halterman Julia , Lees Jason R. , Zhou Xiaoming 
Published: January 2023

Abstract
Th1 and Th17 cells contribute to the pathogenesis of multiple sclerosis (MS) and EAE, an animal model of MS. Th1 cells are characterized by the abundant expression of IFN-γ, whereas Th17 cells express high levels of IL-17. T cell activation leads to the nuclear translocation of nuclear factors and activators of T-cells (NFATs), which contribute to the expression of IFN-γ and IL-17. NFAT5 is the newest member of the NFAT family, however, its role in the pathogenesis of EAE is unknown. We are therefore studying MOG35–55-induced EAE in mice with a global heterozygous knockdown of NFAT5 (NFAT5+/−, NFAT5−/−is lethal) with NFAT5+/+ mice as a control. Interestingly, we found that the knockdown of NFAT5 actually increased EAE induction rate from 65% to 74% and delayed the recovery of EAE, indicating that NFAT5 is protective against the disease. Naïve CD4 cell differentiation reveals that the NFAT5 knockdown increased IFN-γ expression without significantly affecting IL-10 expression in Th1 cells. In vitro differentiation of Th17 cells from NFAT5+/− mice was not successful. IL-6 and protein tyrosine phosphatase SHP-1 have been demonstrated to inhibit IFN-γ expression in Th1 cells. To study the mechanisms by which NFAT5 knockdown increases IFN-γ expression in Th1 cells, we have examined the effects of NFAT5 knockdown on IL-6 and SHP-1. NFAT5 knockdown had no significant effect on IL-6 mRNA level. Instead, our ongoing experiments show that knockdown of NFAT5 reduces SHP-1 mRNA level by 38% (n=3, p=0.11) with a concomitant 44% increase in phosphorylation of Y705 of STAT3, one of its targets (n=3, p=0.2), and has no significant effect on SHP-2 mRNA level. In conclusion: NFAT5 inhibits EAE possibly by suppressing the expression of IFN-γ in Th1 cells.
Structural characteristics of the serum endonuclease Dnase1L3
Authors: McCord Jon Joseph , Harsini Faraz , Sutton Roger Bryan , Keyel Peter A. 
Published: January 2023

Abstract
Systemic Lupus Erythematosus (SLE) is a debilitating autoimmune disease with poly- and mono-genic etiologies. One cause of monogenic SLE is the disruption of Dnase1L3. Dnase1L3 is a serum endonuclease that degrades chromatin in apoptotic microparticles. Dnase1L3 could represent a novel therapy for some cases of SLE. However, the structure of Dnase1L3 is predicted by the 42% identical protein Dnase1. To better understand the structure-function of Dnase1L3, we set out to solve the crystal structure. To solve the crystal structure, we first generated a recombinant His6-Maltose Binding Protein-Dnase1L3 fusion protein. We developed a protocol for purifying Dnase1L3. We isolated Dnase1L3 from the cell lysate using Nickel-NTA beads in maltose buffer, removed purification tags on Dnase1L3 with Tobacco Etch Virus protease, and purified Dnase1L3 on a negatively charged ion exchange column. We then purified Dnase1L3 by size exclusion chromatography to 96.7% final purity. We verified purity at each step by Coomassie staining and, confirmed identity of the final product by Western blot. Recombinant Dnase1L3 robustly degraded plasmid DNA, with a specific activity of 1.83 x 104 U/mg. We found Dnase1L3 had a propensity for small mosaic crystals in a Tris and MgCl2 crystallization buffer. However, larger crystals were grown at 7 °C, compared to 22 °C. Overall, we have developed a new purification method for generating active Dnase1L3 useful for crystallography and other high-purity applications. These applications will further our understanding of Dnase1L3 structure and its function in SLE.
Inflammation targets cell-cycle actors at the onset of autoimmune diabetes (T1D) in pancreatic endocrine cells from the NOD mouse model
Authors: Mora Conchi , Saavedra-Ávila Noemí Alejandra , Sala Ester , Sengupta Upasana , Verdaguer Joan , Stratmann Thomas , Sicinski Peter , Lahti Jill 
Published: January 2023

Abstract
Prior to the massive beta cell demise that leads to autoimmune diabetes (Type 1 Diabetes or T1D), profound profiling changes are imprinted onto the beta cell by an aggressive pro-inflammatory environment that interferes negatively with cell functionality and viability. Ourgoal is to determine key signaling pathways altered in beta cells by the autoimmune assault that are responsible for T1D progression. To this end we have used the T1D-prone NOD (Non Obese Diabetic) mouse model. We have identified several candidate genes the expression of which is altered in the NOD isletendocrine cells prior to the diabetes onset. Interestingly, several of these genes are related to cell cycle progression and are downregulated due to the insulitic attack to the islet. One of these genes is cyclin D3, a D-type cyclin that complexes with either Cdk4 or Cdk6 topromote G1/S cycle progression. The cyclin D3 promoter has binding sequences to NF-kB. However, we have reported that cyclin D3 protects beta cells against cytokine-induced apoptosis and is required for proper beta cell function in a cell-cycle independent fashion. Cdk11 is also affected by inflammation in islet cells and is a cyclin-dependent kinase which is involved in transcription, mitosis and apoptosis. The natural partners of Cdk11 are L-type cyclins, but cyclin D3 has been reported to interact with Cdk11 too. We have addressed whether cdk11 downregulationis responsible for beta cell death.
Thymic development of regulatory T cells by dendritic cells presenting modified peripheral beta cell antigens.
Authors: Lin Yong , Lee Thomas , Zurawski Gerard , Bettini Maria , Bettini Matthew L. 
Published: January 2023

Abstract
Type I Diabetes (T1D) is a T cell-mediated autoimmune disease that destroys insulin producing β cells found within the pancreatic islets of Langerhans. Insulin and Chromogranin A (ChgA) are the only currently known β cell antigens (βAg) necessary to initiate autoimmune diabetes in the non-obese diabetic (NOD) mice; however, expression of ChgA within medullary thymic epithelial cells (mTECs) has not yet been detected. Therefore, tolerance to ChgA may be due in part to peripheral dendritic cells (DCs) presenting ChgA to developing thymocytes and naïve T cells. For example, post-translational modification (PTM) of ChgA by fusion with an insulin peptide increases epitope immunogenicity by forming the neo-antigen, insulin-ChgA fusion peptide (2.5HIP). Pathogenic T cells that are specific for 2.5HIP, which is uniquely expressed in the pancreas, may escape thymic selection due to immunologic ignorance. The relative contribution of thymic and peripheral derived Ag in the selection of βAg specific CD4+ T cells and regulatory T cells (Tregs) remains unclear. To test the role of peripheral Ag exposure on thymic development of βAg specific Tregs, we generated a 50:50 mixed bone marrow chimera using NOD WT (CD45.2 × CD45.1) and BDC2.5 TCR Tg (CD45.1) bone marrow to study the role of peripheral DCs (CD45.2) on developing ChgA T cells. Next, we targeted thymic Langerin+ DCs with anti-Langerin linked to ChgA peptides in BDC2.5 TCR Tg mice. In both experiments, we found robust increase in the ratio and number of ChgA specific Tregs in the presence of the 2.5HIP, in adult and neonatal mice. The results suggest thymic exposure to PTM peptides by DCs enhances β cell specific Treg development and may alter T1D pathogenesis.