Antibody forming cell response to nickel and nickel-coated fly ash in rats

The potential of nickel as nickel chloride, native fly ash and Ni-coated fl y ash to alter pulmonary and systemic immune response was evaluated upon in tratracheal (I/T) exposure of rats. The animals were sensitised with sheep red blood cells (SRBC) through I/T and intraperitoneal (I/P) routes. Nickel exposure resulted in a decrease in the number of antibody forming cells (A FC) in lung associated lymph nodes (LALN) and spleen. In rats exposed to na tive fly ash there was a reduction in the number of AFC in LALN but not in spleen. The results did not demonstrate any significant difference in the i mmunosuppression of fly ash and Ni-coated fly ash exposed rats. The decreas e in AFC formation in Ni-coated fly ash exposed animals was of a lesser mag nitude than in rats exposed to Ni-alone.