Affiliation:
1. Department of Medical Microbiology, College of Veterinary Medicine, University of Georgia, Athens 30602, USA.
Abstract
Fish acquire immunity against the ciliated protozoan parasite Ichthyophthirius multifiliis following sublethal infection. The immune response includes the elaboration of humoral antibodies against a class of abundant surface membrane proteins referred to as immobilization antigens (i-antigens). Antibodies against these proteins immobilize the parasite in vitro, suggesting a potential role for the i-antigens in protective immunity. To test this hypothesis, passive immunization experiments were carried out with naive channel catfish, Ictalurus punctatus, using immobilizing murine monoclonal antibodies (MAbs). Fish were completely protected against lethal challenge following intraperitoneal injection of 20 to 200 micrograms of MAb. Although fish succumbed to infection at lower doses, palliative effects were observed with as little as 2 micrograms of antibody. In experiments in which animals were challenged at various times following inoculation, an inverse relationship between parasite load and serum immobilizing activity was seen. Of seven MAbs which conferred protection, all were immunoglobulin G class antibodies. The only immobilizing MAb that failed to protect was an immunoglobulin M antibody that was absent from surface mucosa as determined by enzyme-linked immunosorbent assay. The implications of these findings for the development of a vaccine against I. multifiliis and immunity against surface pathogens of fish are discussed.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference38 articles.
1. Molecular analysis of antigens targeted by protective antibodies in rapid expulsion of Trichinella spiralis;Arasu P.;Mol. Biochem. Parasitol.,1994
2. Structure and expression of two temperature-specific surface proteins in the ciliated protozoan Tetrahymena thermophila;Bannon G. A.;Mol. Cell. Biol.,1986
3. Immunity of fish occurring in infections with Ichthyophthirius multifiliis, Fouquet, (1876);Bauer O. N.;Akad. Nauk SSSR. Dokl. Novaia Ser.,1953
4. Some host responses of white catfish to Ichthyophthirius multifiliis (Fouquet);Beckert H.;Proc. S. E. Assoc. Game Fish Comm.,1964
5. A comparative study on the use of bovine and murine monoclonal antibodies for passive immunization in cattle;Booman P.;Vet. Immunol. Immunopathol.,1992
Cited by
67 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献