Host regulation of liver fibroproliferative pathology during experimental schistosomiasis via interleukin-4 receptor alpha

PLoS Negl Trop Dis. 2017 Aug 21;11(8):e0005861. doi: 10.1371/journal.pntd.0005861. eCollection 2017 Aug.

Abstract

Interleukin-4 receptor (IL-4Rα) is critical for the initiation of type-2 immune responses and implicated in the pathogenesis of experimental schistosomiasis. IL-4Rα mediated type-2 responses are critical for the control of pathology during acute schistosomiasis. However, type-2 responses tightly associate with fibrogranulomatous inflammation that drives host pathology during chronic schistosomiasis. To address such controversy on the role of IL-4Rα, we generated a novel inducible IL-4Rα-deficient mouse model that allows for temporal knockdown of il-4rα gene after oral administration of Tamoxifen. Interrupting IL-4Rα mediated signaling during the acute phase impaired the development of protective type-2 immune responses, leading to rapid weight loss and premature death, confirming a protective role of IL-4Rα during acute schistosomiasis. Conversely, IL-4Rα removal at the chronic phase of schistosomiasis ameliorated the pathological fibro-granulomatous pathology and reversed liver scarification without affecting the host fitness. This amelioration of the morbidity was accompanied by a reduced Th2 response and increased frequencies of FoxP3+ Tregs and CD1dhiCD5+ Bregs. Collectively, these data demonstrate that IL-4Rα mediated signaling has two opposing functions during experimental schistosomiasis depending on the stage of advancement of the disease and indicate that interrupting IL-4Rα mediated signaling is a viable therapeutic strategy to ameliorate liver fibroproliferative pathology in diseases like chronic schistosomiasis.

MeSH terms

  • Acute Disease
  • Animals
  • Disease Models, Animal
  • Female
  • Fibrosis
  • Host-Parasite Interactions*
  • Liver / pathology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / immunology*
  • Schistosomiasis / genetics
  • Schistosomiasis / immunology*
  • Th2 Cells / immunology*

Substances

  • Il4ra protein, mouse
  • Receptors, Cell Surface