The induction of immune complex deposits in mice by peroral and parenteral administration of mercuric chloride: strain dependent susceptibility.

Female Balb/c and SJL mice exposed to HgCl2 by subcutaneous injection or via drinking water for up to 6 months showed immunostimulation with increased concentrations of immunoglobulins (Ig) in the serum. The Ig isotype pattern was dependent both on the strain and the use of immunopotentiation by addition of Freund's complete adjuvant (FCA). Balb/c mice showed a T cell dependent pattern, whereas the SJL mice developed an increase also in T cell independent isotypes. This latter pattern shifted to show T cell dependency after an initial addition of FCA. FCA also converted the lack of stimulation in C57BL/6J mice to a low response with a T cell dependent isotype pattern. No correlation emerged between the body burden of mercury, as assessed by the concentration in the kidneys, and the degree of immunostimulation by mercury. Mice showing a stimulation of the immune system developed mesangial immune complex (IC) glomerulonephritis and, later on, IC deposits in renal, splenic, and hepatic vessel walls with an isotype pattern corresponding to that seen in the serum.