PROSPECTS FOR THE IMMUNOLOGICAL CONTROL OF RUMINANT GASTROINTESTINAL NEMATODES - NATURAL IMMUNITY, CAN IT BE HARNESSED

Current understanding of the mucosal immune response to nematode paras ites is briefly reviewed with emphasis on the role of the cytokines in terleukins-4 and -12 and gamma interferon (IFN gamma) in the developme nt of T-helper responses in rodents. Data from laboratory animals and ruminants indicate that the events associated with a T-helper 2 (Th2) cell response, notably IgE synthesis, eosinophilia and mucosal mastocy tosis are protective. Evidence that effector mechanisms may vary for d ifferent parasite species is considered. Current gaps in understanding such as the location in the gut and mechanism of antigen processing a nd presentation as well as the relative contribution of non-immunologi cal effector responses, such as gut motility and mucus secretion, to w orm expulsion are discussed. Copyright (C) 1996 Australian Society for Parasitology. Published by Elsevier Science Ltd.