Cadmium and chlorpyrifos inhibit cellular immune response in spleen of rats

Cadmium (Cd) and chlorpyrifos (CPF) are common pollutants co-existing in the environment, and both of them have been reported to have immunotoxicity to organisms. However, the joint effects of these two chemicals on the immune system are still unknown. In this study, the authors used CdCl2 and CPF to study their combined effects on immune functions in the spleen of rats. In in vivo experiments, SD rats were exposed to different doses of CdCl2 (0.7 and 6 mg kg(-1) body weight/day) and CPF (1.7 and 15 mg kg(-1) body weight/day) or their combinations for consecutive 28 days. The proliferation and cytokine production ability of the splenocytes isolated from the treated animals were assessed. In in vitro experiments, the authors used different concentrations of CdCl2 and CPF to treat concanavalin A (Con A)-induced splenocytes isolated from untreated rats. It was found that the combination of CPF and high dose of CdCl2 had a synergistic inhibitory effect on production of IFN-? by spleen cells induced by Con A. The in vitro results showed that two chemicals had different effects on the cell proliferation and cytokine production depending on the exposure doses and time. The authors concluded that this result suggests that exposure to both CdCl2 and CPF at the environmentally-relevant low dose may be potentially more hazardous than exposure to each individual toxicant.

Authors: Wang P, Wang J, Sun YJ, Yang L, Wu YJ. ;Full Source: Environmental Toxicology. 2017 Mar 15. doi: 10.1002/tox.22415. [Epub ahead of print] ;