[Immunogenic and protective characteristics of surface antigens 6 and d of Burkholderia pseudomallei].

AIM: Extraction of complex of Burkholderia pseudomallei antigens 6+d (Ag6+d) and study of its immunogenic and protective characteristics. MATERIALS AND METHODS: Studied antigens were obtained from acrtone-dried cells of B. pseudomallei 57576. Experiments were performed on white mouse model. Microbiological, immunochemical as well as immunological methods were used in the study. RESULTS: It was shown that antigenic complex 6+d has a glycoprotein nature and corresponds to high-polymeric catode-moving antigen 6 with molecular mass 500 kDa and anode-moving antigen d with molecular mass 40 - 55 kDa. Immunogenic and protective characteristics of surface antigenic complex 6+d was studied. It was noted that Ag6+d caused reliable stimulating effect on cellular arm of immune system of white mice appeared in activation of delayed-type hypersensitivity reactions, enhanced phagocytic activity of polymorphonuclear macrophages as well as increased expression of Fc-receptors on macrophages and neutrophils. CONCLUSION: Observed stimulation of cellular immunity by surface antigens was confirmed during study of their protective characteristics on the model of experimental meloidosis in white mice.

[Immunogenicity of surface and capsular antigens of Burkholderia].

Study showed that five (C3, C6, C9, C10, C11) out of ten chromatographic fractions of surface and capsular antigens of B. mallei significantly stimulated cell-mediated immunity that manifested in activation of delayed hypersensivity reactions (DHS) and phagocyteability of noncapsulated avirulent strain of B. mallei with added surface and capsular antigenic complexes. Other fractions did not stimulate cell-mediated immunity, furthermore, fraction C8, which contained capsular biopolymer with mass of 200 kD (Ar8), was characterized by immunosuppressive effect on DHS and phagocytosis. Observed stimulation of cell-mediated immunity by fractions referred above has been confirmed by assessment of their protective effects on the model of experimental melioidosis in white rats. Relationship between markers of humoral and cell-mediated immunity, including markers of specific response, was not observed.

[Role of toxoplasmas in pathology of the vision organ].

The present paper presents data on the major clinical symptoms ofToxoplasma oculopathy in different forms of Toxoplasma infection. It also gives the results of the authors' own laboratory studies of specimens taken from individuals with pathology of the vision organ. They confirm the data available in the literature on that toxoplasmosis frequently occurs in combination with other infections, particularly with Herpes and Cytomegalovirus, Chlamydia, Ureaplasma, and Mycoplasma infections. The signs of eye lesions and a clinical case of an eleven-year-old girl diagnosed as having central recurrent multifocal exudative and hemorrhagic neurochoriorenitis of the right eye are given.

[Prevalence of toxoplasmosis and methods for its laboratory diagnosis].

The review presents data on the prevalence of toxoplasmosis in different countries and regions. It gives a comparative assessment of the methods of serodiagnosis of toxoplasmosis, which permit identification of specific immunoglobulins G, M, A, and E. The authors show a role of laboratory diagnostic techniques in the differentiation of the acute form of toxoplasmosis from its chronic form. They provide the currently available modifications of the basic procedure for enzyme immunoassay, molecular genetic methods, and a direct fluorescent antibody test for the detection of Toxoplasma gondii antigens. The current view of a cellular immune response and its role in monitoring the development of toxoplasmosis are considered.