The expression of self-antigens in medullary thymic epithelial cells(mTECs)is essential for the establishment of immune tolerance,but the regulatory network that controls the generation and maintenance of the multitud...The expression of self-antigens in medullary thymic epithelial cells(mTECs)is essential for the establishment of immune tolerance,but the regulatory network that controls the generation and maintenance of the multitude of cell populations expressing self-antigens is poorly understood.Here,we show that Insm1,a zinc finger protein with known functions in neuroendocrine and neuronal cells,is broadly coexpressed with an autoimmune regulator(Aire)in mTECs.Insm1 expression is undetectable in most mimetic cell populations derived from mTECs but persists in neuroendocrine mimetic cells.Mutation of Insm1 in mice downregulated Aire expression,dysregulated the gene expression program of mTECs,and altered mTEC subpopulations and the expression of tissue-restricted antigens.Consistent with these findings,loss of Insm1 resulted in autoimmune responses in multiple peripheral tissues.We found that Insm1 regulates gene expression in mTECs by binding to chromatin.Interestingly,the majority of the Insm1 binding sites are co-occupied by Aire and enriched in superenhancer regions.Together,our data demonstrate the important role of Insm1 in the regulation of the repertoire of self-antigens needed to establish immune tolerance.展开更多
Crosstalk between thymocytes and thymic epithelial cells is critical for T cell development and the establishment of central tolerance.Medullary thymic epithelial cells(mTECs) play important roles in the late stage of...Crosstalk between thymocytes and thymic epithelial cells is critical for T cell development and the establishment of central tolerance.Medullary thymic epithelial cells(mTECs) play important roles in the late stage of T cell development,especially negative selection and Treg generation.The function of mTECs is highly dependent on their characteristic features such as ectopic expression of peripheral tissue restricted antigens(TRAs) and their master regulator-autoimmune regulator(Aire),expression of various chemokines and cytokines.In this review,we summarize the current understanding of cellular and molecular mechanisms of mTEC development and its functions in T cell development and the establishment of central tolerance.The open questions in this field are also discussed.Understanding the function and underlying mechanisms of mTECs will contribute to the better control of autoimmune diseases and the improvement of immune reconstitution during aging or after infection,chemotherapy or radiotherapy.展开更多
基金supported by the National Natural Science Foundation of China(31970856)the Clinical Frontier Technology Program of the First Affiliated Hospital of Jinan University(JNU1AF-CFTP-2022-a01236)the Science and Technology Program of Guangzhou(202201020042).
文摘The expression of self-antigens in medullary thymic epithelial cells(mTECs)is essential for the establishment of immune tolerance,but the regulatory network that controls the generation and maintenance of the multitude of cell populations expressing self-antigens is poorly understood.Here,we show that Insm1,a zinc finger protein with known functions in neuroendocrine and neuronal cells,is broadly coexpressed with an autoimmune regulator(Aire)in mTECs.Insm1 expression is undetectable in most mimetic cell populations derived from mTECs but persists in neuroendocrine mimetic cells.Mutation of Insm1 in mice downregulated Aire expression,dysregulated the gene expression program of mTECs,and altered mTEC subpopulations and the expression of tissue-restricted antigens.Consistent with these findings,loss of Insm1 resulted in autoimmune responses in multiple peripheral tissues.We found that Insm1 regulates gene expression in mTECs by binding to chromatin.Interestingly,the majority of the Insm1 binding sites are co-occupied by Aire and enriched in superenhancer regions.Together,our data demonstrate the important role of Insm1 in the regulation of the repertoire of self-antigens needed to establish immune tolerance.
基金supported by National Basic Research Program of China,Ministry of Science and Technology(2011CB946103)National Natural Science Foundation of China(81261130022)
文摘Crosstalk between thymocytes and thymic epithelial cells is critical for T cell development and the establishment of central tolerance.Medullary thymic epithelial cells(mTECs) play important roles in the late stage of T cell development,especially negative selection and Treg generation.The function of mTECs is highly dependent on their characteristic features such as ectopic expression of peripheral tissue restricted antigens(TRAs) and their master regulator-autoimmune regulator(Aire),expression of various chemokines and cytokines.In this review,we summarize the current understanding of cellular and molecular mechanisms of mTEC development and its functions in T cell development and the establishment of central tolerance.The open questions in this field are also discussed.Understanding the function and underlying mechanisms of mTECs will contribute to the better control of autoimmune diseases and the improvement of immune reconstitution during aging or after infection,chemotherapy or radiotherapy.