Project description:T cell differentiation is governed by interactions with thymic epithelial cells (TECs) and defects in this process undermine immune function and tolerance. To uncover new strategies to restore thymic function and adaptive immunity in immunodeficiency, we sought to determine the molecular mechanisms that control life and death decisions in TEC. We created a mouse model which specifically deleted the pro-survival gene Mcl1 in TEC. We found that while BCL-2 and BCL-XL were dispensable for TEC homeostasis, MCL-1 deficiency impacted on TEC as early as E15.5, resulting in early thymic atrophy and T cell lymphopenia, with near complete loss of thymic tissue by 2 months of age. MCL-1 was not necessary for TEC differentiation but was continually required for the survival of medullary TEC, including autoimmune regulator (AIRE) expressing TECs and the maintenance of overall thymic architecture. To understand the molecular mechanisms in more detail, RNA-seq profiling was undertaken of cortical and medullary thymic epithelial cells (cTECs and mTECs) from wildtype and knockout mice.
Project description:Analysis of the role of Hipk2 in regulating gene expression in medullary thymic epithelial cells. The whole genome gene signatures of purified mTEC subsets (CD80 low, CD80 high) from TEC-specific Hipk2 knockout mice were compared to mating wildtype control mice (floxed, Cre-). Results provide the up- or down-regulated genes, affected by the Hipk2 gene knockout. Total RNA obtained from isolated CD80 low and CD80 high mTECs of TEC-specific Hipk2 knockout mice compared to control mice mTEC subsets
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:Analysis of the role of Hipk2 in regulating gene expression in medullary thymic epithelial cells. The whole genome gene signatures of purified mTEC subsets (CD80 low, CD80 high) from TEC-specific Hipk2 knockout mice were compared to mating wildtype control mice (floxed, Cre-). Results provide the up- or down-regulated genes, affected by the Hipk2 gene knockout.
Project description:Thymic lymphomas were dissected from Cic adult knockout mice or wildtype mice transplanted with Cic adult knockout progenitors. Tissues were snap-frozen in liquid nitrogen until further analysis. RNAs were purified using the AllPrep DNA/RNA mini kit (Qiagen).
