Mercuric chloride-induced autoimmunity.

This unit describes methods for inducing autoimmune disease in Brown Norway rats through HgCl(2) injections as well for assessing parameters that characterize the disease by serum IgE concentration assays, anti-laminin antibody measurement, and renal immunofluorescence studies to detect autoantibodies. Also covered are disease induction using autoreactive CD4(+) T(H)2 anti-self MHC class II molecules and preparation of T cell lines. IL-4 is produced very early after the first HgCl(2) injection (beginning at day 3, peaking at day 14, and continuing up to day 30). Thus, IL-4 mRNA expression may be detected in spleen and lymph nodes from HgCl(2)-injected BN rats. The fact that HgCl(2) induces in vitro mRNA IL-4 gene expression in normal BN T cells but not in LEW T cells is probably crucial to susceptibility to the development of autoimmunity in the sense that it may condition the development of autoreactive T cells into pathogenic T(H)2 cells; a test for this condition is therefore also included.