Using single-gene deletions to identify checkpoints in the progression of systemic autoimmunity
2003 (English)In: Annals of the New York Academy of Sciences, ISSN 0077-8923, Vol. 987, 236-239 p.Article in journal (Refereed) Published
Systemic lupus erythematosus is a multigenic disorder of unknown etiology. To investigate the roles that specific genes play in lupus, we have examined the disease profiles in mice with single-gene deletions. In total, some 17 genes have been studied. Absence of certain genes, such as CD40L, CD28, or Igh6, abrogated induction of autoimmunity. Other genes, such as Igh5, IL-4, or ICAM-1, had little effect on the development of disease. Intermediate effects were observed in IL-6-deficient mice, while absence of β2-microglobulin resulted in loss of hypergammaglobulinemia and IgG1 autoantibodies, but produced little change in anti-chromatin antibodies or glomerular deposits. The most interesting observations were obtained with genes related to the expression or function of interferon-γ (IFN-γ). Reductions in IFN-γ levels in murine lupus are associated with reductions in both autoantibody levels and immune-complex- mediated pathology. Genes involved in up-regulation of IFN-γ expression, such as IL-12, STAT-4, or ICE, did not significantly influence autoimmunity, whereas absence of IFN-γ or IFN-γ receptor led to greatly reduced autoantibody response and immunopathology. Absence of IRF-1, a gene ex-pressed in response to IFN-γ, resulted in selective retention of anti-chromatin antibodies but little glomerular pathology. These studies suggest that the presence of a baseline level of IFN-γ, rather than increased expression, is important for autoimmunity. Furthermore, as the IRF-1 knockout demonstrates, specific defects in signaling pathways and gene expression subsequent to IFN-γ/IFN-γ receptor interaction may influence only certain disease parameters. It has not escaped our attention that IFN-γ influences the expression and function of other immunologically relevant genes, such as IL-4, IL-6, and β2-microglobulin. Thus, these genes may be part of the downstream events following IFN-γ/IFN-γ receptor interaction that promote the development of autoimmunity.
Place, publisher, year, edition, pages
2003. Vol. 987, 236-239 p.
Autoimmunity, IFN-γ, systemic lupus erythematosus, interleukin
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-26490DOI: 10.1111/j.1749-6632.2003.tb06053.xLocal ID: 11046OAI: oai:DiVA.org:liu-26490DiVA: diva2:247039