Project description:Thymic epithelial cells govern thymic T lymphocyte differentiation and selection. Medullary TECs (mTECs) facilitate the negative selection of self-reactive thymocytes and the differentiation of FOXP3+ regulatory T cells. Medullary TECs are also distinctive for their “promiscuous” gene expression, transcribing thousands of peripheral tissue genes (PTG) that are otherwise only expressed highly in one or two other organs. Much of this PTG expression by mTECs is controlled by the autoimmune regulator, AIRE. To probe the mechanism by which KAT7 promotes AIRE function, we performed ATAC-seq to compare chromatin accessibility in MHCII-high medullary thymic epithelial cells from Kat7-knockout and wildtype mice.
Project description:We profiled medullary thymic epithelial cell subsets from a variety of conditions by scRNA-seq to investigate mechanisms of T-cell tolerance.
Project description:Aire is a transcriptional regulator that induces promiscuous expression of thousands of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We used Affymetrix microarrays to analyze the gene expression patterns of Aire expressing cells (mature mTECs and Thymic B cells) and compared them to control counterparts, namely immature mTECs, cortical Thymic epithelial cells and splenic B cells of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We’ve used Assay for transposase-accessible chromatin using sequencing (ATAC-Seq) on the different thymic epithelial cell populations to assess chromatin accessibility around the Aire locus in these cells. Moreover, we’ve used the indexing-first chromatin immunoprecipitation (iChIP) technique to assess the occupancy of the Irf8 transcription factor in the Aire locus
Project description:Aire is a transcriptional regulator that induces promiscuous expression of thousands of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We used Affymetrix microarrays to analyze the gene expression patterns of Aire expressing cells (mature mTECs and Thymic B cells) and compared them to control counterparts, namely immature mTECs, cortical Thymic epithelial cells and splenic B cells of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We’ve used Assay for transposase-accessible chromatin using sequencing (ATAC-Seq) on the different thymic epithelial cell populations to assess chromatin accessibility around the Aire locus in these cells. Moreover, we’ve used the indexing-first chromatin immunoprecipitation (iChIP) technique to assess the occupancy of the Irf8 transcription factor in the Aire locus
Project description:Aire is a transcriptional regulator that induces promiscuous expression of thousands of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We used Affymetrix microarrays to analyze the gene expression patterns of Aire expressing cells (mature mTECs and Thymic B cells) and compared them to control counterparts, namely immature mTECs, cortical Thymic epithelial cells and splenic B cells of tissue-restricted antigen (TRA) genes in medullary thymic epithelial cells (mTECs). While the target genes of Aire are well characterized, the transcriptional programs regulating its own expression remain elusive. We used Affymetrix microarrays to analyze the gene expression patterns of Aire expressing cells (mature mTECs and Thymic B cells) and compared them to control counterparts, namely immature mTECs, cortical Thymic epithelial cells and splenic B cells.
Project description:We have found that Cdx1 can promote ectopic gene expression in thymic epithelial cells. We isolated MHCIIhi CD80hi medullary thymic epithelial cells from Cdx1-/- and Cdx1+/+ and compare gene expression between the two subsets, also in the context of Cdx1-mediated changes in intestinal epithelial cells.
Project description:Thymic epithelial cells (TECs) govern thymic T lymphocyte differentiation and selection. They can be divided into cortical and medullary TECs based on their anatomical location, function and molecular features. Cortical TECs (cTECs) provide the microenvironment for the commitment of haematopoietic precursors to the T lymphoid lineage and mediate the positive selection of CD4+CD8+ double-positive thymocytes. Medullary TECs (mTECs) facilitate the negative selection of self-reactive thymocytes and the differentiation of FOXP3+ regulatory T (Treg) cells2. Medullary TECs are also distinctive for their "promiscuous" gene expression, transcribing thousands of peripheral tissue genes (PTG) that are otherwise only expressed highly in one or two other organs. Much of this PTG expression by mTECs is controlled by the autoimmune regulator, AIRE. To determine the transcriptional impact of Kat7 loss, we purified mTECs and cTECs from Kat7-knockout and control mice and performed RNA-seq. The mTECs were further divided into MHCII-high and MHCII-low subsets.
Project description:Analysis of gene co-expression patterns in TRA-specific medullary thymic epithelial cell (mTEC) subsets. The whole genome gene signatures of purified mTEC subsets respectively positive for the TRAs Gp2, Pdpn, Cea1, Gad1, Ins2, Tspan8 were compared to their corresponding TRA-negative mTEC subset control. Results provide the enriched and depleted gene expressions in the different subsets.
