Clinical and serologic manifestations of autoimmune disease in MRL-lpr/lpr mice lacking nitric oxide synthase type 2.

Published

Journal Article

Nitric oxide (NO) is an important mediator of the inflammatory response. MRL-lpr/lpr mice overexpress inducible nitric oxide synthase (NOS2) and overproduce NO in parallel with the development of an autoimmune syndrome with a variety of inflammatory manifestations. In previous studies, we showed that inhibiting NO production with the nonselective nitric oxide synthase (NOS) inhibitor NG-monomethyl-arginine reduced glomerulonephritis, arthritis, and vasculitis in MRL-lpr/lpr mice. To define further the role of NO and NOS2 in disease in MRL-lpr/lpr mice, mice with targeted disruption of NOS2 were produced by homologous recombination and bred to MRL-lpr/lpr mice to the N4 generation. MRL-lpr/lpr littermates homozygous for disrupted NOS2 (-/-), heterozygous for disrupted NOS2 (+/-), or wildtype (+/+) were derived for this study. Measures of NO production were markedly decreased in the MRL-lpr/lpr (-/-) mice compared with MRL-lpr/lpr (+/+) mice, with intermediate production by the MRL-lpr/lpr (+/-) mice. There was no detectable NOS2 protein by immunoblot analysis of the spleen, liver, kidney, and peritoneal macrophages of the (-/-) animals, whereas that of (+/+) was high and (+/-) intermediate. The (-/-) mice developed glomerular and synovial pathology similar to that of the (+/-) and (+/+) mice. However, (-/-) mice and (+/-) mice had significantly less vasculitis of medium-sized renal vessels than (+/+) mice. IgG rheumatoid factor levels were significantly lower in the (-/-) mice as compared with (+/+) mice, but levels of anti-DNA antibodies were comparable in all groups. Our findings show that NO derived from NOS2 has a variable impact on disease manifestations in MRL-lpr/lpr mice, suggesting heterogeneity in disease mechanisms.

Full Text

Duke Authors

Cited Authors

  • Gilkeson, GS; Mudgett, JS; Seldin, MF; Ruiz, P; Alexander, AA; Misukonis, MA; Pisetsky, DS; Weinberg, JB

Published Date

  • August 4, 1997

Published In

Volume / Issue

  • 186 / 3

Start / End Page

  • 365 - 373

PubMed ID

  • 9236188

Pubmed Central ID

  • 9236188

International Standard Serial Number (ISSN)

  • 0022-1007

Digital Object Identifier (DOI)

  • 10.1084/jem.186.3.365

Language

  • eng

Conference Location

  • United States