[Immunogenic potential of glanders and melioidosis agents]. / Immunogennyí potentsial vozbuditeleí sapa i melioidoza.

Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine.

[Effect of TRA-system of plasmids RP4 and R68.45 on pseudomonas mallei virulence]. / Vliianie Tra-sistemy plazmid RP4 i R68.45 na virulentnost' vozbuditelia sapa.

In Pseudomonas mallei, spontaneous mutants (Tra- mutants) of the plasmids RP4 and R68.45, losing the ability to transfer at conjugation are formed. The plasmids RP4 and R68.45 with Tra(+)-phenotype caused a decrease in P. mallei virulence for laboratory animals. At the same time, Tra- mutants of these plasmids do not affect P. mallei virulence. The insertion of DNA fragment of about 1900 bp into the plasmid transfer gene regions (tra-2-tra-3) gave rise to RP4 and R68.45 tra mutations detectable on examination.

[Designing the latex test system for express identification of legionella in the external medium and clinical materials]. / Razrabotka lateksnoí test-sistemy dlia uskorennoí identifikatsii vozbuditelia legionelleza vo vneshneí srede i v klinicheskom materiale.

A highly sensitive latex test system for identification of Legionella in the external medium and clinical materials have been designed. Protein antigens and polysaccharide components of the outer membrane of the agent were analyzed. Proteins having a molecular mass of 45, 29, and 24 kDa, as well as a polysaccharide component of LPS were found to be common for all L. pneumophila species. Highly affinic immunoglobulins to the antigenic components obtained were covalently linked with latex particles. The test system developed does not give cross-reactions with other microorganisms. The sensitivity of the system is 10(4) COE/ml. Testing water and clinical material samples confirmed that the developed system is more sensitive than the bacteriological method and the direct fluorescence test. In addition, the system is simple to use, cost-effective, it requires little time (no more than 5 min).

[Stable expression of heterologous proteins in salmonella: problems and approaches to their designing]. / Stabil'naia ékspressiia geterologicheskikh belkov v salmonella: problemy i podkhody k ikh resheniiu.

Live attenuated Salmonella vaccines may be used as carriers of heterologous antigens. The optimum expression system for each heterologous antigen requires to be established on an individual basis. This will ensure that the antigen in question is produced at appropriate levels and in the correctly folded conformation. Different techniques for producing stable recombinant Salmonella strains suitable for their use as bivalent vaccines.