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Neutrophil serine proteases promote IL-1beta generation and injury in necrotizing crescentic glomerulonephritis

Authors

  • A. Schreiber
  • C.T. Pham
  • Y. Hu
  • W. Schneider
  • F.C. Luft
  • R. Kettritz

Journal

  • Journal of the American Society of Nephrology

Citation

  • J Am Soc Nephrol 23 (3): 470-482

Abstract

  • The pathogenesis of anti-neutrophil cytoplasmic antibody (ANCA)-associated necrotizing crescentic GN (NCGN) is incompletely understood. Dipeptidyl peptidase I (DPPI) is a cysteine protease required for the activation of neutrophil serine proteases (NSPs) cathepsin G, neutrophil elastase, and proteinase 3, which are enzymes that modulate inflammation. We used a mouse model of anti-myeloperoxidase (MPO) antibody-induced NCGN to determine whether active NSPs contribute to its pathogenesis. MPO-deficient animals immunized with murine MPO, irradiated, and transplanted with wild-type bone marrow developed NCGN. In contrast, transplantation with bone marrow that lacked DPPI or lacked both neutrophil elastase and proteinase 3 protected mice from NCGN induced by anti-MPO antibody. The kidneys of mice reconstituted with DPPI-deficient bone marrow generated significantly less IL-1beta than did those of mice reconstituted with wild-type bone marrow; similarly, in vitro, DPPI-deficient monocytes produced significantly less IL-1beta in response to anti-MPO antibody than did wild-type monocytes. This reduction in IL-1beta was NSP dependent; exogenous addition of PR3 restored IL-beta production in DPPI-deficient monocytes. Last, the IL-1 receptor antagonist anakinra protected animals against anti-MPO antibody-induced NCGN (16.7%±6.0% versus 2.4%±1.7% crescents), suggesting that IL-1beta is a critical inflammatory mediator in this model. These data suggest that the development of anti-MPO antibody-induced NCGN requires NSP-dependent IL-1beta generation and that these processes may provide therapeutic targets for ANCA-mediated diseases in humans.


DOI

doi:10.1681/ASN.2010080892