Murine lupus: pathogenic mechanisms and genetic origins

Research in several murine models of lupus, reinforced with patient studies, has served to identify key events leading to lupus nephritis. Among these, anti-nuclear antibody (ANA) induced end-organ damage, production of such ANAs by intrinsically hyperactive B-cells, and antigen-specific, cognate T-cell help have been well documented. Though studies in parallel fields of immunology have uncovered a plethora of molecular defects that can potentially drive these key pathogenic events, the actual molecular defects that are responsible for these events in spontaneous lupus remain unknown. Whereas genetically pre-determined triggers are most likely responsible for each of these pathogenic events, humoral and environmental triggers are likely to exert secondary effects, in attenuating or accentuating these mechanisms. Recent genetic studies in mice have allowed researchers to dissect this complex autoimmune disease into a collection of simpler immunological aberrations. These simpler murine models will facilitate the identification and characterization of the fundamental building blocks of lupus, and advance our understanding of the genetics and pathology of this intriguing disease.