Immunodeficiency models in characterization of immune responses to parasites--an overview.
The use of selected immunosuppressant agents and genetically immunodeficient animals in studies designed to characterize the immune response to parasitic infections is reviewed. Immunosuppression induced by commonly used chemicals (corticosteroids and alkylating agents) and ionizing radiation is examined briefly. A greater emphasis is placed on congenitally immunodeficient animals and on immunosuppression induced by purified antisera directed against a variety of cellular specificities. The use of such immunodeficient animals has aided our understanding of the complex interrelationship between host and parasite. However, chemical immunosuppressants and the levels of irradiation used in adoptive cell transfer studies are usually indiscriminant in their toxic effects on a variety of tissues other than those targeted. These affected tissues may be crucial in establishment of the delicate physiological balance required for maintenance of equilibrium between host and parasite. Thus the effects of cytotoxic drugs or irradiation on parasite burdens may reflect alteration of not only immunity, but other essential factors leading to misinterpretation of results. Use of congenitally immunodeficient animals, which are readily repaired by introduction of specific cellular components, may be more useful in dissecting host responses to parasites. In addition, depletion of specific components of the immune system through use of anti-isotype antiserum, for example, is another useful probe. These approaches do not suffer from the generalized cytotoxic effects of chemicals and irradiation, and remove a potentially important and misleading variable from experimental designs. They also allow one to discriminate between non-specific inflammatory and specific immunological factors. The potential pitfalls of broadly used induced immunodeficiency states in studies on parasitisms may now be overcome at least partially by use of highly purified and specific cytotoxic reagents coupled with an ever-increasing array of genetically immunodeficient animal models.
D000305:Adrenal Cortex Hormones / Q000494:pharmacology; D000477:Alkylating Agents / Q000494:pharmacology; D000818:Animals; D000961:Antilymphocyte Serum / Q000276:immunology; D006224:Cricetinae; D003520:Cyclophosphamide / Q000494:pharmacology; D004195:Disease Models, Animal; D006790:Host-Parasite Interactions; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007109:Immunity / Q000187:drug effects / Q000528:radiation effects; D007166:Immunosuppressive Agents / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains / Q000276:immunology; D008819:Mice, Nude / Q000276:immunology; D008954:Models, Biological; D010272:Parasitic Diseases / Q000276:immunology*; D011817:Rabbits; D051381:Rats
D000305:Adrenal Cortex Hormones; D000477:Alkylating Agents; D000961:Antilymphocyte Serum; D007106:Immune Sera; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide