MITOGEN STIMULATION OF LYMPHOCYTES IN CBA MICE EXPOSED TO LEAD AND CADMIUM

CBA mice were exposed to lead acetate or cadmium chloride in drinking water for 10 weeks. Selected groups of these animals were also injected with Bacillus Calmette-Guerin (BCG) during exposure to the metals. The ability of mitogens concanavalin A (Con A) and lipopolysaccharide (LPS) as well as purified protein derivative (PPD) to induce proliferation of splenic lymphocytes was assessed. In general, lead tended to inhibit lymphocyte proliferation by LPS and PPD while cadmium potentiated blastogenesis by these mitogens. The two larger doses of cadmium, 30 and 300 ppm, resulted in intense proliferation which was significant (P < 0.05) for the non-BCG, 300-ppm cadmium group. However, 3 ppm cadmium reduced the lymphocyte response to LPS and PPD which was significant (P < 0.05) for the non-BCG-injected mice. Lead and cadmium did not significantly affect the response of lymphocyte proliferation by Con A. Group variation and interpretation of data are discussed. © 1979.