The effect of cadmium on the immune behaviour of guinea pigs with experimental ascariasis.

The subchronic effect of cadmium on selected immunological parameters was studied in guinea pigs with experimental ascariasis. Cadmium chloride given orally for 28 days caused a considerable suppression of T- and B-cells in the lymphoid organs of intoxicated animals, of the metabolic activity of their peritoneal macrophages and a moderate decline in the level of complement CH50 and AH50 from day 1 to day 28 of the experiment, in comparison with the initial value. After a subsequent infection of the subchronically intoxicated guinea pigs the values for both the cell populations and the macrophage metabolic activity remained considerably suppressed, compared with infected control animals. The phagocytic and metabolic activity of macrophages as well as the CH50 and AH50 level, however, increased conspicuously for a short time after application of heavy metal and after infection but it did not reach the level of the infected group. The level of specific circulating antibodies was not affected by intoxication. Compared with the controls, the mean intensity of infection with Ascaris larvae migrating in the lungs of intoxicated animals increased by 20%. The results have established the negative effect of cadmium on the immunological parameters of the cellular immunity and humoral immunity studied and the impairment of the organism's response to the antigenic stimulus after an A. suum infection.