Acute effects of cadmium on delayed-type hypersensitivity in mice.

A single exposure of mice to cadmium resulted in suppression of the induction of primary delayed-type hypersensitivity (DTH) responses as well as memory T-cell and suppressor T-cell activities, augmenting and inhibiting DTH respectively. Furthermore, cadmium suppressed the expression of already established DTH, in immune mice, even though DTH-effector T cells in the spleen of immune mice were not affected by cadmium injection. Such suppressive effects were demonstrated when cadmium was administered within 2 days before immunization or elicitation for DTH. Cadmium caused also within 2 days in mice thymic involution and splenomegaly. These results indicate that cadmium inhibits not only the generation of certain populations of T lymphocytes for DTH but also some mechanisms in the host involved in the expression of DTH.