Activated phosphoinositide 3-kinaseδsyndrome(APDS)is an autosomal-dominant combined immunodeficiency disorder resulting from pathogenic gain-of-function(GOF)mutations in the PIK3CD gene.Patients with APDS display abn...Activated phosphoinositide 3-kinaseδsyndrome(APDS)is an autosomal-dominant combined immunodeficiency disorder resulting from pathogenic gain-of-function(GOF)mutations in the PIK3CD gene.Patients with APDS display abnormal T cell homeostasis.However,the mechanisms by which PIK3CD GOF contributes to this feature remain unknown.Here,with a cohort of children with PIK3CD GOF mutations from multiple regions of China and a corresponding CRISPR/Cas9 gene-edited mouse model,we reported that hyperactive PI3Kδdisrupted TNaive cell homeostasis in the periphery by intrinsically promoting the growth,proliferation,and activation of TNaive cells.Our results showed that PIK3CD GOF resulted in loss of the quiescence-associated gene expression profile in naive T cells and promoted naive T cells to overgrow,hyperproliferate and acquire an activated functional status.Naive PIK3CD GOF T cells exhibited an enhanced glycolytic capacity and reduced mitochondrial respiration in the resting or activated state.Blocking glycolysis abrogated the abnormal splenic T cell pool and reversed the overactivated phenotype induced by PIK3CD GOF in vivo and in vitro.These results suggest that enhanced aerobic glycolysis is required for PIK3CD GOF-induced overactivation of naive T cells and provide a potential therapeutic approach for targeting glycolysis to treat patients with APDS as well as other immune disorders.展开更多
基金supported by grants from the National Science Foundation of China(81974255)the Public Welfare Scientific Research Project of China(201402012)to X.Z.
文摘Activated phosphoinositide 3-kinaseδsyndrome(APDS)is an autosomal-dominant combined immunodeficiency disorder resulting from pathogenic gain-of-function(GOF)mutations in the PIK3CD gene.Patients with APDS display abnormal T cell homeostasis.However,the mechanisms by which PIK3CD GOF contributes to this feature remain unknown.Here,with a cohort of children with PIK3CD GOF mutations from multiple regions of China and a corresponding CRISPR/Cas9 gene-edited mouse model,we reported that hyperactive PI3Kδdisrupted TNaive cell homeostasis in the periphery by intrinsically promoting the growth,proliferation,and activation of TNaive cells.Our results showed that PIK3CD GOF resulted in loss of the quiescence-associated gene expression profile in naive T cells and promoted naive T cells to overgrow,hyperproliferate and acquire an activated functional status.Naive PIK3CD GOF T cells exhibited an enhanced glycolytic capacity and reduced mitochondrial respiration in the resting or activated state.Blocking glycolysis abrogated the abnormal splenic T cell pool and reversed the overactivated phenotype induced by PIK3CD GOF in vivo and in vitro.These results suggest that enhanced aerobic glycolysis is required for PIK3CD GOF-induced overactivation of naive T cells and provide a potential therapeutic approach for targeting glycolysis to treat patients with APDS as well as other immune disorders.