title: Th2 signals induce epithelial injury in mice and are compatible with the biliary atresia phenotype.
abstract: Biliary atresia (BA) is a destructive cholangiopathy of childhood in which Th1 immunity has been mechanistically linked to the bile duct inflammation and obstruction that culminate in liver injury. Based on reports of decreased Th1 cytokines in some patients and the development of BA in mice lacking CD4+ T cells, we hypothesized that Th1-independent mechanisms can also activate effector cells and induce BA. Here, we tested this hypothesis using Stat1-/- mice, which lack the ability to mount Th1 immune responses. Infection of Stat1-/- mice with rhesus rotavirus type A (RRV) on postnatal day 1 induced a prominent Th2 response, duct epithelial injury and obstruction within 7 days, and atresia shortly thereafter. A high degree of phosphorylation of the Th2 transcription factor Stat6 was observed; however, concurrent inactivation of Stat1 and Stat6 in mice did not prevent BA after RRV infection. In contrast, depletion of macrophages or combined loss of Il13 and Stat1 reduced tissue infiltration by lymphocytes and myeloid cells, maintained epithelial integrity, and prevented duct obstruction. In concordance with our mouse model, humans at the time of BA diagnosis exhibited differential hepatic expression of Th2 genes and serum Th2 cytokines. These findings demonstrate compatibility between Th2 commitment and the pathogenesis of BA, and suggest that patient subgrouping in future clinical trials should account for differences in Th2 status.
authors: Cincinnati Children’s Hospital Medical Center and the Department of Pediatrics of the University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors: Jun
authors: J
authors: Li
authors: Kazuhiko
authors: K
authors: Bessho
authors: Pranavkumar
authors: P
authors: Shivakumar
authors: Reena
authors: R
authors: Mourya
authors: Sujit Kumar
authors: SK
authors: Mohanty
authors: Jorge L
authors: JL
authors: Dos Santos
authors: Irene K
authors: IK
authors: Miura
authors: Gilda
authors: G
authors: Porta
authors: Jorge A
authors: JA
authors: Bezerra
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001656:Biliary Atresia / Q000209:etiology* / Q000276:immunology* / Q000473:pathology; D002648:Child; D002779:Cholestasis / Q000209:etiology / Q000276:immunology / Q000517:prevention & control; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D004848:Epithelium / Q000276:immunology / Q000473:pathology; D006801:Humans; D018793:Interleukin-13 / Q000172:deficiency / Q000235:genetics / Q000276:immunology; D008099:Liver / Q000276:immunology* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D022423:Myeloid Cells / Q000276:immunology / Q000473:pathology; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012401:Rotavirus / Q000472:pathogenicity; D050794:STAT1 Transcription Factor / Q000172:deficiency / Q000235:genetics / Q000276:immunology; D050800:STAT6 Transcription Factor / Q000172:deficiency / Q000235:genetics / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology*
chemical_list: D016207:Cytokines; D018793:Interleukin-13; D012333:RNA, Messenger; D050794:STAT1 Transcription Factor; D050800:STAT6 Transcription Factor; C494080:Stat1 protein, mouse; C494100:Stat6 protein, mouse