Infections caused by the nematode Trichinella spiralis is characterized in the host by an inflammatory response with
cytokine production. In these studies we have detected
TNF alpha,
IL-6, IFN gamma,
IL-4 and
IL-10 in the serum of 10 mice infected with T. spiralis. Moreover, we detected, for the first time, these
cytokines in the serum of mice treated with 4-DPD, a potent antagonist of
vitamin B6 coenzyme which has anti-inflammatory properties. 4-DPD was used at 100, 400, 800 micrograms/bolus for 20 days, starting one day before the
infection. After 15 days of T. spiralis
infection,
TNF alpha reached a maximum level, while
IL-6 was maximal after 7 days, IFN gamma at 20 days and
IL-4 at 14 days.
IL-10 was not affected by the T. spiralis
infection. When the animals were treated with 4-DPD at the reported dosages and infected with T. spiralis the inhibition of
TNF alpha and
IL-6, were dose-dependent in the first 7 days while
IL-4 was reduced only at 400-800 micrograms/bolus. 4-DPD-treated mice did not statistically (P > 0.05) affect the generation of IFN gamma. In healthy animals the production of
cytokines were not measurable, just as it was in non-infected animals treated with 4-DPD. The increase of
cytokines such as,
TNF alpha and
IL-6 may be related to the severity of the disease, boosting the host's resistance to the pathogen and inhibiting parasite survival. In addition, the augmentation of
IL-4 production enhances T and B cells and macrophage responses and may stimulate T-cell antibody-mediated response to the pathogen. 4-DPD, an inhibitor of
IL-1 and inflammatory reactions, proved to be most effective on
TNF alpha and
IL-6, which are mainly produced by macrophages.