The effect of 1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2-dichloroethane(o,p'-DDD) on the immune response in malnutrition.

The drug o,p′-DDD diminished the body weight as well as the weights of the thymus, spleen and adrenals of rats. There was minimal fatty infiltration of the liver. In well-nourished rats o,p′-DDD produced atrophy of both the adrenal cortex and the thymolymphatic organs, but no changes could be detected in kidneys, heart and lungs. The numbers of plaque-forming cells (PFC) and rosette-forming cells (RFC) in the spleen and thymus of the o,p′-DDD treated rats were lower than the controls. The effect of o,p′-DDD was greatest on the adrenal cortex of the malnourished rats with a diminution of plasma corticosteroid concentration and less impairment of the immune response. The numbers of PFC and RFC in the spleen and thymus of the o,p′-DDD-treated malnourished rats were almost equal to that of their controls. It was interesting to observe that o,p′-DDD seemed to affect PFC more adversely than RFC. In comparison to the controls, thymocytes and spleen cells of the o,p′-DDD-treated rats responded better to phytohaemagglutinin (PHA) than to pokeweed mitogen (PWM).