Project description:Genomewide microarray analysis of murine tolerant, self-antigen specific CD8 T cells to identify genes and pathways underlying peripheral T cell tolerance Gene signature of tolerant CD8 T cells was compared to the signatures of naïve T cells, memory T cells, rescued T cells (=tolerant T cells undergoing homeostatic proliferation in lymphopenic, tolerogenic Alb:GAG mice), and re-tolerized T cells (=previously rescued T cells post homeostatic proliferation isolated from lymphoreplete wild-type B6 mice). Total RNA obtained from various sort-purified transgenic CD8 T cell subsets (naïve, memory, tolerant, rescued, and re-tolerized) isolated from spleens of different host mice
Project description:To elucidate transcriptional differences between naïve, tolerant and memory CD8+ T cells, genome-wide gene expression profiling was performed. The indicated cell populations were purified from immunized or naïve Rag-/- TCR mice by cell sorting and RNA was extracted labeled and hybridized to an Affymetrix custom mouse array GNF1M GeneChip. RNA from sorted samples was prepared, split into two aliquots prior to making labeled cDNA, so that two arrays were used for each cell population.Alterations in transcript levels were determined through pair wise comparisons of naïve cells to either memory or tolerant CD8+ T cells. Keywords: cell type
Project description:Differentiation of CD8+ T lymphocytes into effector and memory cells is key for an adequate immune response and relies on complex interplay of pathways that convey signals from cell surface to nucleus. In this study, we fractionated four CD8+ T cell subtypes; naïve, recently activated effector, effector and memory cells into membrane, cytosol, soluble nucleus, chromatin-bound and cytoskeleton compartments. Using LC-MS/MS analysis, identified peptides were matched to human peptides/proteins (SwissProt). Compartment fractionation and gel-LC-MS separation identified 2399 proteins in total. Among these 735 were detected in all five, 241 in four, 257 in three, 368 in two and 798 found in only one fraction. Comparison between the two most different subsets, naïve and effector, yielded 146 significantly regulated proteins.
Project description:Histone methylations play a major role in regulating the chromatin state and gene expression, yet little is known about their involvement in differential gene expression and function of memory CD8 T cells. Here, we report a genome-wide analysis of two histone H3 methylations (H3K4me3 and H3K27me3) and gene expression in naïve, central (TCM) and effector (TEM) memory CD8 T cells. Analysis of 16,314 annotated genes in CD8 T cell subsets revealed that gene expression were positively correlated with the levels of H3K4me3 and negatively correlated with the levels of H3K27me3 in these gene loci. The correlation between differential H3K4me3 orH3K27me3 levels with gene expressions in memory CD8 T cells displayed four distinct modes: repressive, active, poised, and bivalent, reflecting their complex regulation and different function of these genes. Furthermore, accessible chromatin states of different gene loci were preferentially influenced by different histone modifications as demonstrated here high levels of H3K9ac found in active gene loci without high levels of H3K4me3. These findings reveal a histone methylation based complex regulation of differential gene expression in memory CD8 T cells. Thus, change of chromatin structure mediated by histone methylation may serve a fundamental basis for the rapid transcriptional response of memory CD8 T cells. genome-wide analysis of two histone H3 methylations (H3K4me3 and H3K27me3) in naïve, central (TCM) and effector (TEM) memory CD8 T cells.
Project description:Genomewide microarray analysis of murine tolerant, self-antigen specific CD8 T cells to identify genes and pathways underlying peripheral T cell tolerance Gene signature of tolerant CD8 T cells was compared to the signatures of naïve T cells, memory T cells, rescued T cells (=tolerant T cells undergoing homeostatic proliferation in lymphopenic, tolerogenic Alb:GAG mice), and re-tolerized T cells (=previously rescued T cells post homeostatic proliferation isolated from lymphoreplete wild-type B6 mice).
Project description:We investigated the genomic landscape of histone modifications in antigen-experienced CD8+ T cells. Using a ChIP-Seq approach coupled with global gene expression profiling [GSE67825], we generated genome-wide histone H3 lysine 4 (H3K4me3) and H3 lysine 27 (H3K27me3) trimethylation maps in distinct subsets of CD8+ T cells - naïve, stem cell memory, central memory, and effector memory. To gain insight into how histone architecture is remodeled during the differentiation of activated T cells
Project description:(1) Murine CD4 T cells: naïve vs peptide treated and naïve vs peptide+LPS treated. (2) Murine CD8 T cells naïve vs HY-specific cells from tolerant mice and naïve vs cells from rejecting mice
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.