Abstract
Evidence is presented to indicate that Plasmodium berghei merozoites, but not trophozotites, have an antiphagocytic capsule. The capsule appears to form around the developing merozoties of the schizont in the parasitophorous vacuole. Serum from animals immune to P. berghei reacts with this capsule. After reaction with immune serum, the antiphagocytic action of the capsule is lost. By the process of binding serum protein, the capsule becomes electron dense and can be readily visuallzed as the surface coat by electron microscopy. At physiological temperatures, phagocytosis by macrophages rapidly follows adhesion of antibody-coated parasites. Both tight and loose phagosomes are formed.
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Selected References
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- Bannister L. H., Butcher G. A., Dennis E. D., Mitchell G. H. Structure and invasive behaviour of Plasmodium knowlesi merozoites in vitro. Parasitology. 1975 Dec;71(3):483–491. doi: 10.1017/s0031182000047247. [DOI] [PubMed] [Google Scholar]
- Belcher R. W., Carney J. F., Monahan F. G. An electron microscopic study of phagocytosis of Candida albicans by polymorphonuclear leukocytes. Lab Invest. 1973 Dec;29(6):620–627. [PubMed] [Google Scholar]
- Chow J. S., Kreier J. P. Plasmodium berghei: adherence and phagocytosis by rat macrophages in vitro. Exp Parasitol. 1972 Feb;31(1):13–18. doi: 10.1016/0014-4894(72)90042-2. [DOI] [PubMed] [Google Scholar]
- Cochrane A. H., Aikawa M., Jeng M., Nussenzweig R. S. Antibody-induced ultrastructural changes of malarial sporozoites. J Immunol. 1976 Mar;116(3):859–867. [PubMed] [Google Scholar]
- Doyle J. J., Behin R., Mauel J., Rowe D. S. Antibody-induced movement of membrane components of Leishmania enriettii. J Exp Med. 1974 May 1;139(5):1061–1069. doi: 10.1084/jem.139.5.1061. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dumont A., Robert A. Electron microscopic study of phagocytosis of Histoplasma capsulatum by hamster peritoneal macrophages. Lab Invest. 1970 Sep;23(3):278–286. [PubMed] [Google Scholar]
- Green T. J., Kreier J. P. Demonstration of the role of cytophilic antibody in resistance to malaria parasites (Plasmodium berghei) in rats. Infect Immun. 1978 Jan;19(1):138–145. doi: 10.1128/iai.19.1.138-145.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hamburger J., Kreier J. P. Antibody-mediated elimination of malaria parasites (plasmodium berghei) in vivo. Infect Immun. 1975 Aug;12(2):339–345. doi: 10.1128/iai.12.2.339-345.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hamburger J., Kreier J. P. Plasmodium berghei: use of free blood stage parasites to demonstrate protective humoral activity in the serum of recovered rats. Exp Parasitol. 1976 Oct;40(2):158–169. doi: 10.1016/0014-4894(76)90078-3. [DOI] [PubMed] [Google Scholar]
- Krier J. P., Hamburger J., Seed T. M., Saul K., Green T. Plasmodium berghei: characteristics of a selected population of small free blood stage parasites. Tropenmed Parasitol. 1976 Mar;27(1):82–88. [PubMed] [Google Scholar]
- Ladda R., Aikawa M., Sprinz H. Penetration of erythrocytes by merozoites of mammalian and avian malarial parasites. J Parasitol. 1969 Jun;55(3):633–644. [PubMed] [Google Scholar]
- Mason S. J., Aikawa M., Shiroishi T., Miller L. H. Further evidence for the parasitic origin of the surface coat on Malaria merozoites. Am J Trop Med Hyg. 1977 Mar;26(2):195–197. doi: 10.4269/ajtmh.1977.26.195. [DOI] [PubMed] [Google Scholar]
- Miller L. H., Aikawa M., Dvorak J. A. Malaria (Plasmodium knowlesi) merozoites: immunity and the surface coat. J Immunol. 1975 Apr;114(4):1237–1242. [PubMed] [Google Scholar]
- Mitchell G. H., Butcher G. A., Cohen S. Isolation of blood-stage merozoites from Plasmodium knowlesi malaria. Int J Parasitol. 1973 May;3(3):443–445. doi: 10.1016/0020-7519(73)90126-4. [DOI] [PubMed] [Google Scholar]
- Mitchell G. H., Butcher G. A., Cohen S. Merozoite vaccination against Plasmodium knowlesi malaria. Immunology. 1975 Aug;29(2):397–407. [PMC free article] [PubMed] [Google Scholar]
- Prior R. B., Kreier J. P. Plasmodium berghei freed from host erythrocytes by a continuous-flow ultrasonic system. Exp Parasitol. 1972 Oct;32(2):239–243. doi: 10.1016/0014-4894(72)90030-6. [DOI] [PubMed] [Google Scholar]
- Saul K. W., Kreier J. P. Plasmodium berghei: immunization of rats with antigens from a population of free parasites rich in merozoites. Tropenmed Parasitol. 1977 Sep;28(3):302–318. [PubMed] [Google Scholar]
- Siddiqui W. A. An effective immunization of experimental monkeys against a human malaria parasite, Plasmodium falciparum. Science. 1977 Jul 22;197(4301):388–389. doi: 10.1126/science.406671. [DOI] [PubMed] [Google Scholar]
- Trager W., Jensen J. B. Human malaria parasites in continuous culture. Science. 1976 Aug 20;193(4254):673–675. doi: 10.1126/science.781840. [DOI] [PubMed] [Google Scholar]