Delayed type hypersensitivity in zinc deficient adult mice: impairment and restoration of responsivity to dinitrofluorobenzene.

Seven-week-old A/J mice were divided into three uniform groups and fed: 1) a zinc deficient diet (0.6 micrograms Zn/g) ad libitum (deficient); 2) a zinc adequate diet (55 micrograms Zn/g) ad libitum (control); and 3) a zinc adequate diet (55 micrograms An/g) with intake restricted to the average daily amount consumed by the zinc deficient group (restricted). After 26 days on the diets, part of the mice from each dietary group were percutaneously sensitized with dinitrofluorobenzene (DNFB) to assess of restricted mice to DNFB [Stimulation Index (S.I.) of 1.98] was only moderately reduced compared to controls (S.I. of 2.53). Zinc deficient mice, on the other hand, gave a very poor response to DNFB (S.I. of 1.23). Thus, DTH is yet another branch of the immune system affected by a suboptimal intake of dietary zinc. To assess the ability of deficient mice to regenerate DTH responsivity the remaining deficient mice were refed diets containing adequate zinc (55 micrograms Zn/g). After 21 days of nutritional repletion, previously zinc deficient mice gave DTH responses nearly identical to that of control mice.