Surface antigens ofToxoplasma gondii

Abstract

Monoclonal antibodies reacting with pellicular antigens of Toxoplasma gondii tachyzoites have been selected among hybridomas produced against this organism by immunofluorescence assay. These antigens have been further characterized by immunofluorescence on living zoites, Western immunoblotting and immunoprecipitation of lactoperoxidase surface radio-iodinated tachyzoite lysates. The simultaneous characterization of 5 different surface antigens (P43, P35, P30, P23, P22) some of which have already been studied individually allowed a better definition of these antigens and the characterization of a yet undescribed surface molecule (P23).

Toxoplasma gondii: Ultrastructural localization of specific antigens and inhibition of intracellular multiplication by monoclonal antibodies

“…The molecules located on the surface of the parasite are important to invade the host cell and SAG-1 (P30) plays a major role in invasion (Couvreur et al, 1988;Grimwood and Smith, 1995). Ultrastructural localization of antigenic protein of T. gondii was examined by a ultrathin section using an immunogold technique with Toxoplasma specific mAbs.…”

The microneme protein MIC3 of Toxoplasma gondii is a secretory adhesin that binds to both the surface of the host cells and the surface of the parasite

“…MAbs T4 2F3 and T4 1E5 were isolated during the screening of hybridomas produced against T. gondii as described elsewhere (Couvreur et al, 1988;Sadak et al, 1988). MAb T8 2C10 was obtained independently using similar procedures (Tomavo et al, 1991).…”

Evidence for glycosyl-phosphatidylinositol anchoring of Toxoplasma gondii major surface antigens.

“…This pellicle is probably involved in zoite motility and host cell invasion; it is also a major target of the host immune response. Immunochemical analysis of surface antigens of T. gondii tachyzoites led to the characterization of four major radioiodinatable proteins (3,12,16,17) which were named P43, P35, P30, and P22 according to their apparent molecular weights after electrophoresis. Apart from Kasper et al (17), who concluded that antigen P30 was an integral membrane protein from its behavior on charge shift electrophoresis, no information on the interaction of these proteins with membrane lipids has been published.…”