Chemically induced immunomodulation in domestic food animals.

There is extensive research underway on development of chemical immunomodulators for use in humans. This research is primarily driven by the need for therapeutic immunomodulators for use in patients with cancer or AIDS. Currently, there are no chemicals approved as immunomodulators by the Food and Drug Administration for use in domestic food animals. There is considerable potential for applying the rapid advances in immunomodulation research to benefit domestic animals. In domestic food animals, immunomodulators have the greatest potential for prevention and perhaps therapy in early stages of infectious diseases associated with immunosuppression. There are many different causes for immunosuppression and many different molecular mechanisms responsible for defective function of immune cells. It is unlikely that any one immunomodulator will be capable of preventing or reversing all of these various causes of immunosuppression. Therefore, research is needed to understand the mechanisms of immunosuppression and the mechanism of action of immunomodulators so that rational approaches can be developed for their prophylactic and therapeutic use. Without this information and information on effective dosages and duration of action, attempts to use immunomodulators clinically are likely to produce discouraging results.