Project description:We compared differences in fetal and adult T cells by performing whole genome profiling on sort-purified T cells (naïve CD4+ and Treg cells) from human fetal specimens (18-22 gestational weeks) and adult specimens (age 25-40 years old). Fetal and Adult Naïve CD4+ T cells phenotype: CD3+CD4+CD45RA+CCR7+CD27+, Fetal and Adult CD4+CD25+ Treg phenotype: CD3+CD4+CD25bright Four different groups were analyzed: Fetal Naïve CD4+ T cells, Adult Naïve CD4+ T cells, Fetal Treg cells, Adult Treg cells. For each group three independent donors were analyzed.
Project description:Epigenome profiling has led to the paradigm that promoters of active genes are decorated with H3K4me3 and H3K9ac marks. Data revealed an extensively euchromatic epigenome with heterochromatin restricted to variant surface antigen gene families (VSA) and a number of genes hitherto unlinked to VSA. The vast majority of the genome shows an unexpected pattern of enrichment of H3K4me3 and H3K9ac at intergenic regions and depletion at genes. Chip-chip (and cDNA) from Plasmodium falciparum strain NF54 asexual blood stages with H3, H3K4me3, H3K9me3 and H3K9ac
Project description:Both genetic and environmental factors are implicated in Type 1 Diabetes (T1D). Since environmental factors can trigger epigenetic changes, we hypothesized that variations in histone posttranslational modifications (PTMs) at the promoter/enhancer regions of T1D susceptible genes may be associated with T1D. We therefore evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the chromatin-immunoprecipitation-linked-to-microarray approach to profile key histone PTMs, including H3-lysine-4 trimethylation (H3K4me3), H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac at genes within the T1D susceptible loci in lymphocytes, and H3K4me3, H3K9me2, H3K9Ac and H4K16Ac at the IDDM1 region in monocytes of T1D patients and healthy controls separately. We screened for potential variations in histone PTMs using computational methods to compare datasets from T1D and controls. Interestingly, we observed marked variations in H3K9Ac levels at the upstream regions of HLA-DRB1 and HLA-DQB1 within the IDDM1 locus in T1D monocytes relative to controls. Additional experiments with THP-1 monocytes demonstrated increased expression of HLA-DRB1 and HLA-DQB1 in response to interferon- and TNF-treatment that were accompanied by changes in H3K9Ac at the same promoter regions as that seen in the patient monocytes. These results suggest that the H3K9Ac status of HLA-DRB1 and HLA-DQB1, two genes highly associated with T1D, may be relevant to their regulation and transcriptional response towards external stimuli. Thus, the promoter/enhancer architecture and chromatin status of key susceptible loci could be important determinants in their functional association to T1D susceptibility. We evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the ChIP-chip approach to profile key histone PTMs, including histone H3K4me3, H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac, at genes within the T1D susceptible loci in lymphocytes.
Project description:Histone 3 lysine 9 acetylation (H3K9ac) at transcription initiation sites is a well known marker for actively initiating and transcribing genes.The purpose of the present study was to investigate the association between H3K9ac and diverse progress of HBV infection. We employed chromatin immunoprecipitation microarray (ChIP-chip) technology to profile and compare the variations of genes H3K9ac in CD4 T cells of the CHB patients at the different clinic phases. The results showed there were lots of different genes with H3K9ac among the study groups. Comparison of genomic H3K9ac status in CD4 T cells from CHB patients at the different clinic phases
Project description:Both genetic and environmental factors are implicated in Type 1 Diabetes (T1D). Since environmental factors can trigger epigenetic changes, we hypothesized that variations in histone posttranslational modifications (PTMs) at the promoter/enhancer regions of T1D susceptible genes may be associated with T1D. We therefore evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the chromatin-immunoprecipitation-linked-to-microarray approach to profile key histone PTMs, including H3-lysine-4 trimethylation (H3K4me3), H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac at genes within the T1D susceptible loci in lymphocytes, and H3K4me3, H3K9me2, H3K9Ac and H4K16Ac at the IDDM1 region in monocytes of T1D patients and healthy controls separately. We screened for potential variations in histone PTMs using computational methods to compare datasets from T1D and controls. Interestingly, we observed marked variations in H3K9Ac levels at the upstream regions of HLA-DRB1 and HLA-DQB1 within the IDDM1 locus in T1D monocytes relative to controls. Additional experiments with THP-1 monocytes demonstrated increased expression of HLA-DRB1 and HLA-DQB1 in response to interferon- and TNF-treatment that were accompanied by changes in H3K9Ac at the same promoter regions as that seen in the patient monocytes. These results suggest that the H3K9Ac status of HLA-DRB1 and HLA-DQB1, two genes highly associated with T1D, may be relevant to their regulation and transcriptional response towards external stimuli. Thus, the promoter/enhancer architecture and chromatin status of key susceptible loci could be important determinants in their functional association to T1D susceptibility.
Project description:Gene expression data from wild-type and Bcl6-/- naive CD4 T cells In order to find genes regulated by Bcl6 in follicular helper T cells Naïve CD4 T cells were sorted from wild-type (WT) and T cell-specific conditional Bcl6-/- (KO) mice-- 8 samples, 4 WT and 4 KO