Previous Article | Next Article 
Infect Immun. 1986 March; 51(3): 760-764
Inhibition of a penetration-enhancing factor of Toxoplasma gondii by monoclonal antibodies specific for rhoptries.
J D Schwartzman
ABSTRACT
The anterior organelles of the coccidian parasite Toxoplasma gondii have long been suspected of playing a role in the ability of this organism to actively penetrate a wide range of host cells. A series of four monoclonal antibodies (produced by spleen cells from mice immunized with whole, killed T. gondii fused with Sp 2/0-Ag14 myeloma cells) recognized anterior organelles of T. gondii in indirect immunofluorescence assays. These antibodies (Tg 13, Tg 31, Tg 49, and Tg 112) were of the immunoglobulin G (IgG) class, had different enzyme-linked immunosorbent assay titers, and partially competed with each other in a solid-phase immunoassay with whole, dried T. gondii as the antigen. It was observed by immunofluorescence that all antibodies detected anterior structures, which under some conditions of fixation and extraction appeared to be multiple rodlike organelles resembling rhoptries. As determined by ultrastructure immunocytology, Tg 49 recognized electron-dense bodies consistent with rhoptries or micronemes in parasites that had been fixed in 2% paraformaldehyde and extracted with Triton X-100 to allow antibody penetration. An assay of penetration enhancement, in which conditioned medium (from fibroblast monolayers completely lysed by T. gondii) increased the number of plaques produced by a standard inoculum of T. gondii on fresh monolayers, was inhibited by equal amounts of all four monoclonal antibodies, in degrees closely related to their enzyme-linked immunosorbent assay titers. These antibodies appeared to link a penetration-enhancing factor with the rhoptries of T. gondii.
Infect Immun. 1986 March; 51(3): 760-764
This article has been cited by other articles:
-
Bushkin, G. G., Ratner, D. M., Cui, J., Banerjee, S., Duraisingh, M. T., Jennings, C. V., Dvorin, J. D., Gubbels, M.-J., Robertson, S. D., Steffen, M., O'Keefe, B. R., Robbins, P. W., Samuelson, J.
(2010). Suggestive Evidence for Darwinian Selection against Asparagine-Linked Glycans of Plasmodium falciparum and Toxoplasma gondii. Eukaryot Cell
9: 228-241
[Abstract]
[Full Text]
-
DeRocher, A. E., Coppens, I., Karnataki, A., Gilbert, L. A., Rome, M. E., Feagin, J. E., Bradley, P. J., Parsons, M.
(2008). A Thioredoxin Family Protein of the Apicoplast Periphery Identifies Abundant Candidate Transport Vesicles in Toxoplasma gondii. Eukaryot Cell
7: 1518-1529
[Abstract]
[Full Text]
-
Bradley, P. J., Ward, C., Cheng, S. J., Alexander, D. L., Coller, S., Coombs, G. H., Dunn, J. D., Ferguson, D. J., Sanderson, S. J., Wastling, J. M., Boothroyd, J. C.
(2005). Proteomic Analysis of Rhoptry Organelles Reveals Many Novel Constituents for Host-Parasite Interactions in Toxoplasma gondii. J. Biol. Chem.
280: 34245-34258
[Abstract]
[Full Text]
-
Nakaar, V., Ngo, H. M., Aaronson, E. P., Coppens, I., Stedman, T. T., Joiner, K. A.
(2003). Pleiotropic effect due to targeted depletion of secretory rhoptry protein ROP2 in Toxoplasma gondii. J. Cell Sci.
116: 2311-2320
[Abstract]
[Full Text]
-
Channon, J. Y., Suh, E. I., Seguin, R. M., Kasper, L. H.
(1999). Attachment Ligands of Viable Toxoplasma gondii Induce Soluble Immunosuppressive Factors in Human Monocytes. Infect. Immun.
67: 2547-2551
[Abstract]
[Full Text]
-
Liang, F. T., Granstrom, D. E., Zhao, X. M., Timoney, J. F.
(1998). Evidence that Surface Proteins Sn14 and Sn16 of Sarcocystis neurona Merozoites Are Involved in Infection and Immunity. Infect. Immun.
66: 1834-1838
[Abstract]
[Full Text]
-
Lingelbach, K, Joiner, K.
(1998). The parasitophorous vacuole membrane surrounding Plasmodium and Toxoplasma: an unusual compartment in infected cells. J. Cell Sci.
111: 1467-1475
[Abstract]
-
Joiner, K., Fuhrman, S., Miettinen, H., Kasper, L., Mellman, I
(1990). Toxoplasma gondii: fusion competence of parasitophorous vacuoles in Fc receptor-transfected fibroblasts. Science
249: 641-646
[Abstract]