[Evaluation of the immunological activity and safety of group B meningococcal vaccine prepared from a natural complex of specific polysaccharide and outer membrane proteins].

Immunological activity and safety of group B meningococcal vaccine prepared from a natural complex of specific polysaccharide and outer membrane proteins were under study. The immunological safety of the vaccine was evaluated by the absence of antibodies to denaturated and native DNA (d-DNA and n-DNA). As shown with the use of the enzyme immunoassay (EIA), the administration of the vaccine did not induce antibody formation to d-DNA and n-DNA during the observation period.

[The molecular parameters of a meningococcal serogroup B protein-polysaccharide vaccine].

Methods for the evaluation of the molecular parameters of B polysaccharide (B-PS) in meningococcal protein-polysaccharide vaccine of group B are proposed. The comparison of two proposed methods, the passive hemagglutination inhibition test and rocket immunoelectrophoresis (RIEP), has shown that the latter method has the highest degree of correlation with the chemical method of the detection of B-PS, which is often hindered by lactose added as a bulking agent. RIEP may be recommended for the standardization and control of the commercial preparations of group B meningococcal vaccine.

[The effect of the conditions for Neisseria meningitidis cultivation on the protein composition in the protein-polysaccharide complex--the base of meningococcal serogroup B vaccine].

New data concerning the influence of cultivation conditions on the synthesis aimed at producing immunologically active antigens of group B Neisseria meningitides were obtained. The combination of conditions (deficiency in ions of iron, pH of the medium, growth phase of the culture) capable of essentially increasing (9- to 28-fold) the content of iron-dependent protein with a mol. wt.

[The isotypic characteristics of antibodies in persons inoculated with a serogroup-A meningococcal polysaccharide vaccine].

In this work the results of the study of specific antibodies (Ab), isotypes IgM, IgG, IgA, types kappa and lambda, in 235 serum samples from 27 adults immunized with group A meningococcal polysaccharide vaccine (AMPV) in a single injection of 50 microg and from 20 control subjects are presented. The study was made by the method of sandwich EIA. The study revealed that in a month after the injection of the vaccine the intensive synthesis of IgA, IgG and IgA Ab and their subsequent circulation for 2 years were observed; 3 years after immunization (the term of observation) the prevalence of IgG and IgA antibodies was registered.

[The relationship between the immunological efficacy of a dried meningococcal group-A polysaccharide vaccine and the molecular parameters of the group-A polysaccharide].

This work deals with the problem of relationship between the molecular parameters of group A meningococcal polysaccharide and its immunological effectiveness for laboratory animals and humans. The depolymerization of group A polysaccharide contained in the vaccine leads to a decrease in its capacity of inducing the production of hemagglutinating (19S and 7S) and bactericidal IgA antibodies in humans, as well as inducing an increase in the number of cells producing IgA antibodies in the spleen of immunized mice and the appearance of circulating IgA antibodies in their sera. As shown in this investigation, fully developed immune response to group A meningococcal vaccine may be achieved in humans only if the content of group A high-molecular polysaccharide in the vaccine is not less than 70%.

[Immune bacteriolysis reaction in the assessment of immunological effectiveness of serogroup B meningococcal vaccine].

The immunological efficacy of serogroup B meningococcal protein-polysaccharide vaccine was studied in newly developed immune bacteriolysis test. Serogroup B meningococcus strains had different sensitivities to the bactericidal effects of immune sera. A single injection of the vaccine caused an induction of bactericidal antibodies to meningococcus vaccinal strain.

[The reactogenicity and antigenic activity of a meningococcal group B vaccine made from a natural complex of the specific polysaccharide and outer membrane proteins].

Group B meningococcal vaccine consisting of the natural complex of specific polysaccharide and outer membrane protein (OMP) has been shown to be moderately reactogenic, safe with respect to the effect of undermining tolerance to human brain tissue antigens and to produce no allergization of humans. The vaccine under study possesses antigenic activity: (a) immunization with this vaccine ensures the fourfold rise of the level of antibodies to the group-specific polysaccharide of group B meningococcus in about 80% of persons with the initially low level of antibodies, this percentage being retained during the whole period of observation, i. e.

[The diagnostic value of a meningococcal-B erythrocyte diagnostic agent based on the group-specific polysaccharide].

In this work the diagnostic value of group B meningococcal erythrocyte diagnosticum was determined. 585 blood serum samples taken from adult donors were studied: 220 samples from practically healthy persons and 365 samples from 144 patients with meningococcal infection and purulent bacterial meningitis of nonmeningococcal etiology. Group B meningococcal erythrocyte diagnosticum was found to possess serological activity and to reveal the growth of specific antibodies in the sera of patients with meningococcal infection, serologically confirmed by the isolation of group B meningococcal culture, in 100% of cases on weeks 2-3 of the disease.

[The sorption of a protein-polysaccharide complex isolated from Neisseria meningitidis serogroup B on aluminum hydroxide gels and the immunological activity of the sorbed preparations].

The protein-polysaccharide complex, isolated from group B N. meningitidis, is a variant of vaccine for the prophylaxis of group B N. meningitidis infection.

[The protective activity of polyclonal and monoclonal antibodies to the lipopolysaccharide of Neisseria meningitidis serogroup A in in vivo experiments].

The protective activity of the sera of mice immunized with the preparations of native and detoxified N. meningitidis lipopolysaccharide (LPS), group A, as well as with monoclonal antibodies to N. meningitidis antigens, groups A and B, was studied on the mucin model of meningococcal infection.

[A comparative study of the immunogenicity of 2 group-B meningococcal vaccines in monkeys].

The comparative study of two group B meningococcal vaccines manufactured in the USSR and in Cuba was made. The vaccine manufactured in the USSR contained the noncovalent compound of group B Neisseria meningitidis polysaccharide and outer membrane protein, and the Cuban vaccine contained group B N. meningitidis outer membrane proteins and group C N.

[The protective activity of the detoxified lipopolysaccharide of Neisseria meningitidis serogroup A in in vivo experiments].

The immunogenic potency, toxicity, homologous and heterologous protective activity of lipopolysaccharide preparations obtained from serogroup A N. meningitidis (LPS A) were studied in animal experiments. These preparations were shown to possess very high protective activity.

[Evaluation of the effectiveness of group-A and -C meningococcal polysaccharide vaccines by molecular parameters].

Chromatographic properties of meningococcal polysaccharides and vaccines of serogroups A and C prepared at the G. N. Gabrichevskiĭ Moscow Research Institute of Epidemiology and Microbiology were studied during determination of their molecular parameters by gel filtration on sepharose 4B.

[Immunologic properties of purified and complex preparations of group-B meningococcal polysaccharide].

The complex preparations of group B meningococcal polysaccharide have been found to be capable of inducing primary immune response in mice, while purified group B polysaccharide has proved to be immunologically inert. As revealed in this investigation, the intravenous injection to mice of the optimum doses of the complex preparation of group B polysaccharide leads to the increased number of specific B-antibody-forming cells in their spleens and to a rise in B-antibody titers in their sera; besides, the time course of the process has been studied. Both preparations have been found capable of forming the immunological memory in mice if booster immunization is made with the complex preparation of group B polysaccharide.

[Isolation and characteristics of a specific polysaccharide of group-B meningococci].

The optimum conditions for the isolation and purification of the specific polysaccharide of group B meningococci have been developed. The advantages of the use of synthetic culture media for growing the initial bacterial culture have been demonstrated. The purified polysaccharides have been found to contain about 70% of sialic acid and less than 1% of protein and nucleic acid admixtures.

[Continuous synchronously dividing cultures of the B meningococcus serogroup].

Cultures of Neisseria meningitidis Bc5S No. 125 with continuous and synchronous cell fission have been obtained. The synchronization index is 0.

[Immunological effectiveness of a dried group-A meningococcal polysaccharide vaccine].

The immunological effectiveness of dried group A meningococcal polysaccharide vaccine, developed at the Gabrichevsky Research Institute of Epidemiology and Microbiology, Moscow, for children aged 5-14 years was studied. The intensiveness of the immune response of children to 0.5 ml of the vaccine introduced in a single injection was evaluated by a rise in the level of agglutinating antibodies to group A meningococcal polysaccharide in the sera of the vaccinees 3-4 weeks after immunization with the following optimum doses: 25 micrograms for children aged 5-8 years, 50 micrograms for children aged 9-13 years and 75 micrograms for children aged 14 years and over.

[Immunogenicity of the surface polysaccharide of serotype A meningococci possessing different physico-chemical properties].

The influence of changes in the physico-chemical parameters of serogroup A meningococcal polysaccharide on its immunogenicity for mice was studied by means of passive local hemolysis in gel and the passive hemagglutination test. The polysaccharide was depolymerized by heating at 100 degrees C for 5, 30 and 120 minutes; during this process the progressing decrease of the molecular weight and the content of O-acetyl groups in the preparation could be observed. Mice showed high sensitivity to changes in the above-mentioned physico-chemical parameters, which was manifested by a sharp drop in the intensity of the immune response of the animals to the heated samples of the antigen.