Toxoplasma gondii -intracellular parasite. Tue article presents selected data concerning invasion and intracellular life of obligate intracellular parasite Toxoplasma gondii in susceptible bosts.
Ubiquitous parasite of humans and endothermic animals Toxoplasma gondii (type Apicomplexa), identified by Nicolle and Manceaux over 100 years ago, is still an object of numerous extensive studies bringing very interesting and often even surprising observations as that announced in the title [1].
The paper presents antigenic structure of T. gondii tachyzoites and bradyzoites in respect of potential use of some chosen antigens for diagnostic and immunoprophylactic purposes.
Toxoplasma gondii, the etiological agent of toxoplasmosis, is an Apicomplexa obligate intracellular protozoan parasite, which is able to infect any nucleated cell of numerous endothermic vertebrates. The combined abilities to actively penetrate host cells and perfectly control the fate of the parasite-containing vacuole (parasitophorus vacuole, PV) contribute to the remarkable global success of Toxoplasma as an intracellular parasite. Very broad host range and the relative ease of growth both in cell cultures in vitro and in vivo suggest that the parasite is able to manipulate the host cell apoptotic machinery. The article describes different aspects of host-parasite interplay focusing on molecular modifications of infected host cells.
The determination of the anti-Toxoplasma immunoglobulin G (IgG) avidity is a diagnostic method which has been intensively used for differentiating of recent and more distant Toxoplasma gondii infection in a single serum sample. Finding of low avidity anti-Toxoplasma IgG antibodies usually indicates recently acquired infection, while the presence of high avidity IgG antibodies contradicts to recently acquired infection. Recently, a number of commercial kits have been introduced for determining the avidity of anti-Toxoplasma IgG antibodies. Therefore, it seemed advisable to make comparative studies in order to investigate the correspondences and discrepancies in the results obtained by the different kits. We compared and analysed the results obtained with four commercially available anti-Toxoplasma IgG avidity assays. They were expected to give well correlated results, but some differences between the kits were observed in the ranking of anti-Toxoplasma IgG avidity ("high" or "low" or "borderline"). Among others, differences in the dilution method or differences in the type, quality or quantity of the Toxoplasma antigen used in the different assays might explain the observed divergences.
Cell structure and metabolism of the parasite Toxoplasma gondii - new aspects. The article is based on newly published data concerning cell structure (cytoskeleton and cytoplasmic organelle) and biochemistry of the protozoon Toxoplasma gondii, many of which can be applied in therapy of toxoplasmosis.