Abstract
The nucleosome has attracted attention because it is a possible primary antigen that initiates autoimmune reactions and also seems to play a key role in glomerular injury in systemic lupus erythematosus (SLE). It is not immunogenic in nonautoimmune individuals, however, and many other protein or peptide antigens inducing anti-DNA antibodies in normal animals have been reported recently. Various mechanisms have been proposed to account for this, including idiotype-anti-idiotype, hapten-carrier, molecular mimicry, and others. In addition to the initial immune responses to such antigens, breakdown of self-tolerance influenced by genetic factors or hormonal dysregulation may be necessary preconditions for occurrence of the disease.