Project description:Cellular binary fate decisions require the progeny to silence genes associated with the alternative fate. The major subsets of alpha:beta T cells have been extensively studied as a model system for fate decisions. While the transcription factor RUNX3 is required for the initiation of Cd4 silencing in CD8 T cell progenitors, it is not required to maintain the silencing of Cd4 and other helper T lineage genes. The other runt domain containing protein, RUNX1, silences Cd4 in an earlier T cell progenitor, but this silencing is reversed whereas the gene silencing after RUNX3 expression is not reverse. Therefore, we hypothesized that RUNX3 and not RUNX1 recruits other factors that maintains the silencing of helper T lineage genes in CD8 T cells. To this end, we performed a proteomics screen of RUNX1 and RUNX3 to determine candidate silencing factors.
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.
Project description:Comparison of gene expression profile of CD4+ CD25+, CD4+ CD25- CD45RBlow LAG3+ and CD4+ CD25- CD45RBlow LAG3- T cells. Naive CD4+CD25-CD45RBhigh T cells were used as a reference for pair comparison with values from the three other subsets.
Project description:Type 1 regulatory T (Tr1) cells are one of the regulatory T cell subsets that are characterized by the production of high amount of IL-10 and lack of FOXP3 expression. Lymphocyte-activation gene 3 (LAG3) is a CD4 homologue molecule and we have previously reported that LAG3 is expressed on IL-10 producing regulatory T cells. However, naturally occurring Tr1 cells in human secondary lymphoid tissue have not been detected. We identified CD4+CD25-LAG3+ T cells in human tonsil. We compared mRNA expression of five CD4+ T cell subsets in tonsil using microarray analysis (CD4+CD25-LAG3+ T cells, CD4+CD25-CXCR5+PD-1+ follicular helper T cells (TFH), CD4+CD25+ T cells, CD4+CD25-LAG3-CD45RO+ cells and CD4+CD25-LAG3-CD45RO- cells). A human tonsil was obtained from a patient undergoing routine tonsillectomy, and five tonsillar CD4+ T cell subsets were sorted (each 1 x 10^5 cells). There is no biological replication.
Project description:A comparison of CD4+CD25+ and CD4+CD25- splenic T cells. Although both subsets have regulatory T cell activity in an induced transplantation tolerance model, the CD4+CD25+ subsets are apparently 10 fold enriched in regulatory T cells. SAGE analysis is performed and compared both on resting and CD3 activated populations. Keywords: other
Project description:Type 1 regulatory T (Tr1) cells are one of the regulatory T cell subsets that are characterized by the production of high amount of IL-10 and lack of FOXP3 expression. Lymphocyte-activation gene 3 (LAG3) is a CD4 homologue molecule and we have previously reported that LAG3 is expressed on IL-10 producing regulatory T cells. However, naturally occurring Tr1 cells in human secondary lymphoid tissue have not been detected. We identified CD4+CD25-LAG3+ T cells in human tonsil. We compared mRNA expression of five CD4+ T cell subsets in tonsil using microarray analysis (CD4+CD25-LAG3+ T cells, CD4+CD25-CXCR5+PD-1+ follicular helper T cells (TFH), CD4+CD25+ T cells, CD4+CD25-LAG3-CD45RO+ cells and CD4+CD25-LAG3-CD45RO- cells).
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.
Project description:Naïve T cells were obtained by StemCell CD4+ T cell isolation kit of spleen from Mettl3 KO and WT mice followed by FACS sorting (CD4+CD25-CD45RB-Hi). Raw sequencing reads were aligned to the mouse genome (mm10) with Tophat, and gene expression levels were measured by Cufflinks.