CD19 regulates skin and lung fibrosis via Toll-like receptor signaling in a model of bleomycin-induced scleroderma.

Published

Journal Article

Mice subcutaneously injected with bleomycin, in an experimental model of human systemic sclerosis, develop cutaneous and lung fibrosis with autoantibody production. CD19 is a general "rheostat" that defines signaling thresholds critical for humoral immune responses, autoimmunity, and cytokine production. To determine the role of CD19 in the bleomycin-induced systemic sclerosis model, we investigated the development of fibrosis and autoimmunity in CD19-deficient mice. Bleomycin-treated wild-type mice exhibited dermal and lung fibrosis, hyper-gamma-globulinemia, autoantibody production, and enhanced serum and skin expression of various cytokines, including fibrogenic interleukin-4, interleukin-6, and transforming growth factor-beta1, all of which were inhibited by CD19 deficiency. Bleomycin treatment enhanced hyaluronan production in the skin, lung, and sera. Addition of hyaluronan, an endogenous ligand for Toll-like receptor (TLR) 2 and TLR4, stimulated B cells to produce various cytokines, primarily through TLR4; CD19 deficiency suppressed this stimulation. These results suggest that bleomycin induces fibrosis by enhancing hyaluronan production, which activates B cells to produce fibrogenic cytokines mainly via TLR4 and induce autoantibody production, and that CD19 deficiency suppresses fibrosis and autoantibody production by inhibiting TLR4 signals.

Full Text

Duke Authors

Cited Authors

  • Yoshizaki, A; Iwata, Y; Komura, K; Ogawa, F; Hara, T; Muroi, E; Takenaka, M; Shimizu, K; Hasegawa, M; Fujimoto, M; Tedder, TF; Sato, S

Published Date

  • June 2008

Published In

Volume / Issue

  • 172 / 6

Start / End Page

  • 1650 - 1663

PubMed ID

  • 18467694

Pubmed Central ID

  • 18467694

Electronic International Standard Serial Number (EISSN)

  • 1525-2191

International Standard Serial Number (ISSN)

  • 1525-2191

Digital Object Identifier (DOI)

  • 10.2353/ajpath.2008.071049

Language

  • eng