Loss of Immune Function and DNA Damage in Cadmium- Induced Altered Cytokine Milieu – an In Vitro Study

The testis though recognized as an immuneprivileged organ, there are a number of immunocompetent cells like macrophages, neutrophils and monocytes within the testicular interstitial compartment which give evidence of testicular immune response. Among them, macrophage population is the largest one and is known to influence the function of the neighboring Leydig cells. Testicular macrophages are the largest population of immune cells in the rodent testes. Exposure to cadmium chloride in-vitro is known to inhibit the testicular macrophage functions. But the extent of effect or the mechanism thereof is not well elucidated. The present study examined the extent of immunomodulatory effect in murine testes after in-vitro exposure to cadmium. To elucidate the immunomodulatory effects of cadmium, cell function studies such as morphological alteration, phagocytosis, intracellular killing mechanism, DNA fragmentation, enzyme activity (nitric oxide, myeloperoxidase synthase) and proinflammatory cytokines TNF-α and IL-6 release assays were performed in testicular macrophages isolated from cadmium-treated and control group of adult male BALB/c mice. The in vitro study shows morphological alteration in cadmium treated (in-vitro) group along with DNA damage as compared to control. It also indicates an impairment of the microbial capacity due to suppressed phagocytosis and intracellular killing consorted to a reduction of inflammatory response. This is due to decrease of oxygen species both reactive nitrogen and in the phagocytic niche in the presence of cadmium ions. Thus it is observed that the enzyme release is also affected due to in-vitro cadmium treatment. The present work shows that treatment with cadmium is responsible for significant alteration in macrophage function.