Aicardi–Goutières syndrome(AGS)is a rare genetic disease caused by mutations in nine genes that are all involved in nucleic acid metabolism or sensing.1,2 The three RNASEH2 subunits represent the most frequently...Aicardi–Goutières syndrome(AGS)is a rare genetic disease caused by mutations in nine genes that are all involved in nucleic acid metabolism or sensing.1,2 The three RNASEH2 subunits represent the most frequently mutated genes in AGS patients,1,3 and mutations in RNASEH2 subunits lead to the accumulation of endogenous RNA:DNA hybrids that may trigger an interferon-α-mediated immune response4 through the activation of pattern recognition receptors(PRRs).5 PRRs perform surveillance on extracellular,endosomal,and cytosolic compartments to identify signs of infection:endogenous nucleic acids that are inappropriately cleared may enter and accumulate in the cytoplasm,driving inflammation and autoimmune diseases.6 This accumulation may be the cause of the clinical autoimmune phenotype of AGS patients carrying RNASEH2 mutations.A proven effective cure for AGS has not been discovered,and targeting these two pathways may lead to a treatment that improves patients’immunological symptoms.Hydroxychloroquine(HCQ)interferes with normal antigen processing and presentation and is widely used in the clinical treatment of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis.7 HCQ is also a well-known inhibitor of autophagy that prevents the degradation of autolysosomes.This drug inhibits acidification and maturation of endosomes and increases the pH in lysosomes,resulting in the inhibition of their main functions,such as downstream cell signaling through TLRs.7 Therefore,the aim of our work was to investigate whether HCQ is able to modulate the abnormal inflammatory response driven by RNA:DNA hybrids.展开更多
基金supported by grants from the Italian Ministry of Health RC 2018-2019 to IRCCS Mondino Foundation,Pavia,Italy.
文摘Aicardi–Goutières syndrome(AGS)is a rare genetic disease caused by mutations in nine genes that are all involved in nucleic acid metabolism or sensing.1,2 The three RNASEH2 subunits represent the most frequently mutated genes in AGS patients,1,3 and mutations in RNASEH2 subunits lead to the accumulation of endogenous RNA:DNA hybrids that may trigger an interferon-α-mediated immune response4 through the activation of pattern recognition receptors(PRRs).5 PRRs perform surveillance on extracellular,endosomal,and cytosolic compartments to identify signs of infection:endogenous nucleic acids that are inappropriately cleared may enter and accumulate in the cytoplasm,driving inflammation and autoimmune diseases.6 This accumulation may be the cause of the clinical autoimmune phenotype of AGS patients carrying RNASEH2 mutations.A proven effective cure for AGS has not been discovered,and targeting these two pathways may lead to a treatment that improves patients’immunological symptoms.Hydroxychloroquine(HCQ)interferes with normal antigen processing and presentation and is widely used in the clinical treatment of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis.7 HCQ is also a well-known inhibitor of autophagy that prevents the degradation of autolysosomes.This drug inhibits acidification and maturation of endosomes and increases the pH in lysosomes,resulting in the inhibition of their main functions,such as downstream cell signaling through TLRs.7 Therefore,the aim of our work was to investigate whether HCQ is able to modulate the abnormal inflammatory response driven by RNA:DNA hybrids.
