Idiotypic characteristics of immunoglobulins associated with human systemic lupus erythematosus. Association of high serum levels of IdGN2 with nephritis but not with HLA class II genes predisposing to nephritis

Regulation of autoimmunity

Despite the prevalence of self-reactive T cells, the healthy organism is not in a state of all-out war. Potent regulatory mechanisms exist at every level to permit the successful integration of the various aspects of the immune system, allowing only minor skirmishes, which ordinarily can be neutralized.

Idiotypic and immunochemical differences of anti-DNA antibodies of a lupus patient during active and inactive disease

IgG anti-DNA antibodies of a lupus patient during active and inactive stages of her disease were studied. There were no significant differences in the amounts, in double-stranded DNA-binding activity, or in complement-fixing ability between purified IgG anti-DNA antibodies of both stages. However, their idiotype (Id) expressions were different as revealed by binding to rabbit anti-Ids raised against each of the anti-DNA antibodies. Moreover, the active stage anti-DNA antibodies had higher activity and less cross-reactivity with polynucleotides. Dominant anti-DNA populations during the active and inactive stages of systemic lupus erythematosus are clonally and qualitatively different.