biostudies-literatureKomori SMEXT | Japan Society for the Promotion of ScienceJapan Agency for Medical Research and Developmente2304943120https://www.ebi.ac.uk/biostudies/studies/S-EPMC10440595biostudies-literatureUnknown120(33)Conventional dendritic cells (cDCs) are required for peripheral T cell homeostasis in lymphoid organs, but the molecular mechanism underlying this requirement has remained unclear. We here show that T cell-specific CD47-deficient (<i>Cd47</i>^ΔT) mice have a markedly reduced number of T cells in peripheral tissues. Direct interaction of CD47-deficient T cells with cDCs resulted in activation of the latter cells, which in turn induced necroptosis of the former cells. The deficiency and cell death of T cells in <i>Cd47</i>^ΔT mice required expression of its receptor signal regulatory protein α on cDCs. The development of CD4⁺ T helper cell-dependent contact hypersensitivity and inhibition of tumor growth by cytotoxic CD8⁺ T cells were both markedlProceedings of the National Academy of Sciences of the United States of AmericaCD47 promotes peripheral T cell survival by preventing dendritic cell-mediated T cell necroptosis.PMC1044059521H0480721cm0106308h000622K1549422K0850422674074Nitta EAfroj TKaneko YRespatika DEndoh HSaito YIida-Norita RKotani TYoshida HKomori SOhnishi HMatozaki TOduori OSNitta RMurata YTakai TNishimura TSugihara RfalseCD47 promotes peripheral T cell survival by preventing dendritic cell-mediated T cell necroptosis.Conventional dendritic cells (cDCs) are required for peripheral T cell homeostasis in lymphoid organs, but the molecular mechanism underlying this requirement has remained unclear. We here show that T cell-specific CD47-deficient (<i>Cd47</i>^ΔT) mice have a markedly reduced number of T cells in peripheral tissues. Direct interaction of CD47-deficient T cells with cDCs resulted in activation of the latter cells, which in turn induced necroptosis of the former cells. The deficiency and cell death of T cells in <i>Cd47</i>^ΔT mice required expression of its receptor signal regulatory protein α on cDCs. The development of CD4⁺ T helper cell-dependent contact hypersensitivity and inhibition of tumor growth by cytotoxic CD8⁺ T cells were both markedl2023-01-01T00:00:00Z2023 Aug2025-04-22T05:32:10.329Z2025-04-05T21:23:40.945ZS-EPMC104405953754929010.1073/pnas.2304943120