Project description:mRNA profiles of Salmonella specific tissue resident memory CD4 T cells and effector memory CD4 T cells from the liver, and splenic effector memory CD4 T cells
Project description:IFN -YFP reporter mice (Jax# 017580) were immunized intravenously with attenuated Salmonella enterica serovar Typhimurium intravenously. 45 days later, tissue resident memory CD4 T cells (CD69+ YFP+) in the liver, effector memory CD4 T cells (CD69- YFP+) in the liver, and effector memory CD4 T cells (CD69- YFP+) in the spleeen were sorted and RNA was sequenced
Project description:Memory CD4 T cells are critical to human immunity, yet it is unclear if viral inflammation during memory formation has long-term consequences. Here, we compared transcriptional and epigenetic landscapes of Spike (S)-specific memory CD4 T cells in 24 individuals whose first exposure to S was via SARS-CoV-2 infection or mRNA vaccination. Nearly two years after memory formation, S-specific CD4 T cells established by infection remained enriched for transcripts related to cytotoxicity and for interferon-stimulated genes, likely due to a chromatin accessibility landscape altered by inflammation. Moreover, S-specific CD4 T cells primed by infection had reduced proliferative capacity in vitro relative to vaccine-primed cells. Furthermore, the transcriptional state of S-specific memory CD4 T cells was minimally altered by booster immunization and/or breakthrough infection. Thus, these data demonstrate the durable imprint of inflammation on CD4 T cell memory which affected function and may have consequences for long-term immunity.
Project description:Memory T cells are primed for rapid responses to antigen; however, the molecular mechanisms responsible for priming remain incompletely defined. CpG methylation in promoters is an epigenetic modification, which regulates gene transcription. Using targeted bisulfite sequencing, we examined methylation of 2100 genes (56,000 CpG) mapped by deep sequencing to T cell activation in human naïve and memory CD4 T cells. 466 CpGs (132 genes) displayed differential methylation between naïve and memory cells. 21 genes exhibited both differential methylation and gene expression before activation, linking promoter DNA methylation states to gene regulation; 6 genes encode proteins closely studied in T cells while 15 genes represent novel targets for further study. 39 genes exhibited reduced methylation in memory cells coupled with increased gene expression with activation compared to naïve cells, revealing specific genes more rapidly expressed in memory compared to naïve cells and potentially regulated by DNA methylation. These findings define a DNA methylation signature unique to memory CD4 T cells and correlated with activation-induced gene expression. Targeted bisulfite sequencing of primary human naïve and memory CD4 T cells at rest and 48 hours post-activation.
Project description:We used microarray analysis to identify specific molecular mechanisms controlling Th17 cell differentiation in HFD mice Memory phenotype CD4 T cells derived from ND or HFD mice were selected for RNA extraction and hybridization on Affymetrix microarrays.
