Zinc administration restores the impaired immune response observed in mice receiving excess copper by oral route.

To study if treatment with zinc (Zn) was able to restore to normal levels the depressed immune response determined by oral administration of excess copper (Cu), groups of mice receiving 100 ppm or 200 ppm of Cu in the drinking water for 8 weeks, were injected ip once a week with Zn (1.14 mg/kg of body weight), throughout the experimental period. Administration of Zn restored to normal levels the proliferative response to mitogens and the antibody response to sheep red blood cells in the group of mice receiving 100 ppm of Cu in the drinking water. Similarly, the treatment with Zn significantly enhanced the depressed proliferative response to mitogens and the antibody response to sheep red blood cells of mice receiving 200 ppm of Cu in the drinking water. By contrast, increment in Zn supply was not able to modify the high production of auto-antibodies observed in animals receiving excess Cu. The results suggest that the impairment of the immune response observed in animals receiving excess Cu could be in part due to antagonistic interactions between this cation and Zn.