Vertebrates typically harbor a rich gastrointestinal microbiota, which has co-evolved with the host over millennia and is essential for several of its physiological functions, in particular maturation of the immune system. Recent studies have highlighted the importance of a single bacterial species, segmented filamentous bacteria (SFB), in inducing a robust T helper (Th)17 population in the small intestinal lamina propria (SI-LP) of the mouse gut. Consequently, SFB can promote IL-17-dependent immune and autoimmune responses, gut-associated as well as systemic, including inflammatory arthritis and experimental autoimmune encephalomyelitis. Here, we exploit the incomplete penetrance of SFB colonization of NOD mice in our animal facility to explore its impact on the incidence and course of type-1 diabetes in this prototypical, spontaneous model. There was a strong co-segregation of SFB-positivity and diabetes protection in females, but not in males, which remained relatively disease-free regardless of the SFB status. In contrast, insulitis did not depend on SFB colonization. SFB-positive, but not SFB-negative, females had a substantial population of Th17 cells in the SI-LP, which was the only significant, repeatable difference in the examined T cell compartments of the gut, pancreas or systemic lymphoid tissues. Th17 signature transcripts dominated the very limited SFB-induced molecular changes detected in SI-LP CD4+ T cells. Thus, a single bacterium, and the gut immune system alterations associated with it, can either promote or protect from autoimmunity in predisposed mouse models, likely reflecting their variable dependence on different Th subsets.
Naturally transmitted segmented filamentous bacteria segregate with diabetes protection in nonobese diabetic mice.
Age, Specimen part
View SamplesNotch receptors direct the differentiation of T helper (Th) cell subsets, but their influence on regulatory T (TR) cell responses is obscure. Interruption of Notch signaling in TR cells resulted in a super-regulatory phenotype, with suppression of TR cell Th1 programming and apoptosis as well as Th1 cell responses in systemic inflammation. In contrast, gain of function Notch1 signaling in TR cells resulted in lymphoproliferation, dysregulated Th1 responses and autoimmunity. To determine mechanisms by which Notch signaling may alter TR cell function, we compared the transcriptional profiles of splenic TR cells of Foxp3EGFPCre mice with those of Foxp3EGFPCreR26N1c/N1c (gain of function Notch signaling), Foxp3EGFPCreRBPJ/ (loss of function canonical Notch signaling), and Foxp3EGFPCreR26N1c/N1cRBPJ/ mice (gain of function/canonical loss of function Notch signaling).
Control of peripheral tolerance by regulatory T cell-intrinsic Notch signaling.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A special population of regulatory T cells potentiates muscle repair.
Sex, Age, Specimen part, Treatment, Time
View SamplesA phenotypically and functionally distinct population of CD4+ Foxp3+ T cells (Tregs) rapidly accumulates in acutely injured skeletal muscle of mice, just as invading myeloid-lineage cells switch from a pro-inflammatory to a pro-regenerative state. Analysis of gene expression of Tregs and CD4+Foxp3- T cells (Tconvs) from injured muscle and spleen revealed that the transcriptome of muscle Treg cells is distinct from that of splenic Tregs. A set of genes is uniquely expressed by muscle Tregs, while another set is over-expressed by the two muscle populations vis--vis their two spleen counterparts.
A special population of regulatory T cells potentiates muscle repair.
Sex, Age, Specimen part, Treatment, Time
View SamplesA comparative analysis of gene expression of injured skeletal muscle from wild-type (Foxp3-DTR-) and Treg-depleted (Foxp3-DTR+) mice showed that Treg cells are critical for effective repair and regeneration of acute injury of skeletal muscle.
A special population of regulatory T cells potentiates muscle repair.
Sex, Age, Specimen part, Treatment, Time
View SamplesGlobal gene expression analysis of injured skeletal muscle showed that amphiregulin (Areg), a growth factor over-expressed by muscle Treg cells, enhances muscle regeneration both in the presence and in the absence of Tregs.
A special population of regulatory T cells potentiates muscle repair.
Age, Specimen part, Treatment, Time
View SamplesCD4+Foxp3+ regulatory T cells (Tregs) accumulate in skeletal muscle from dystrophin-deficient mdx mice. Analysis of global gene expression in muscles from mdx mice treated with anti-CD25 compared with muscles from mdx mice treated with control antibody revealed that Tregs partially protect mdx mice from muscle pathology and promote muscle repair/regeneration.
A special population of regulatory T cells potentiates muscle repair.
Sex, Age, Specimen part, Treatment
View SamplesWithin the human gut reside diverse microbes coexisting with the host in a mutually advantageous relationship. We comprehensively identified the modulatory effects of phylogenetically diverse human gut microbes on the murine intestinal transcriptome. Gene-expression profiles were generated from the whole-tissue intestinal RNA of mice colonized with various single microbial strains. The selection of microbe-specific effects, from the transcriptional response, yielded only a small number of transcripts, indicating that symbiotic microbes have only limited effects on the gut transcriptome overall. Moreover, none of these microbe-specific transcripts was uniformly induced by all microbes. Interestingly, these responsive transcripts were induced by some microbes but repressed by others, suggesting different microbes can have diametrically opposed consequences.
Mining the Human Gut Microbiota for Immunomodulatory Organisms.
Sex, Age, Specimen part
View SamplesHere we analyzed the transcriptional profile of S-IECs sorted from GF and monocolonized mice (C. histolyticum and B. adolescentis), as well as SPF mice colonized with SFB or not.
Identifying species of symbiont bacteria from the human gut that, alone, can induce intestinal Th17 cells in mice.
Sex, Age
View SamplesWe analyzed the transcriptional profile of small-intestinal lamina propria (SI-LP) CD4+ T cells isolated from germ-free and mice monocolonized with Bifidobacterium adolescentis, SFB, and Nexabiotic (a 23-strain, Th17-inducing, probiotic mix). Overall design: CD4+ T cells were double-sorted from mice directly into lysis buffer.
Identifying species of symbiont bacteria from the human gut that, alone, can induce intestinal Th17 cells in mice.
Sex, Age, Specimen part, Cell line, Subject
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