[The Neisseria meningitidis serotypes and subtypes circulating among bacterial carriers in Moscow (1989-1991)]. / Serotipy i subtipy Neisseria meningitidis, tsirkuliruiushchikh sredi bakterionositelei v Moskve (1989--1991 gg.).

N. meningitidis strains isolated from 218 healthy carriers in 1989-1991 in closed communities of adults, irrespective of cases of meningococcal infection registered in these communities, were characterized with a variety of different type and subtype antigens. Only in 139 strains (63.76%) their types and/or subtypes could be determined with the use of a set of 6 serotypes and 11 subtypes of monoclonal antibodies. 26 group B strains and 31 group C strains had multiple antigenic composition. 13 group A strains were found to be more homogeneous: 8 of them, isolated in one area, belonged, according to Dr. Achtman's data, to a definite clone VI-1, heretofore unknown. No prevailing serotype/subtype could be revealed, which reflected the wide heterogeneity of N. meningitidis at the period of the decrease of morbidity in meningococcal infection. The observed stability of serotype/subtype of strains, isolated from the same carriers and circulating in the same communities, suggests that the serotype/subtype of N. meningitidis is a valuable epidemiological marker.

[The role of fibronectin in the pathogenesis of meningococcal infection]. / Rol' fibronektina v patogeneze meningokokkovoi infektsii.

We have characterized an interaction of 20 strains of Neisseria meningitidis serogroups A, B, C, 29E, W-135 and Z with immobilized fibronectin of human plasma. The adhesion of meningococci to fibronectin was determined by the extent of piliated cells and did not depend on the meningococcal serogroup. Binding of non-piliated or weakly piliated strains (2-5% of piliated cells in the stock) was sufficiently greater than those piliated (8-10%), where the adhesion to fibronectin was not at all observed. The examination of two well-piliated strains showed that the loss of pili resulted in the increase of bacterial adhesion to fibronectin. Constants of association and dissociation of piliated and non-piliated strains to fibronectin were calculated. The role of meningococci-fibronectin interaction in the pathogenesis of meningococcal infection is discussed.

[Immunochemical properties of a protective cross-reacting antigen of meningococci]. / Immunokhimicheskie svoistva protektivnogo perekrestnogo reagiruiushchego antigena meningokokkov.

The study of protective cross-reacting antigenic preparations isolated from meningococci of groups A and C in the blot immunoassay has shown the presence of a group of proteins with a molecular weight ranging from 23 to 31 KD and common for 8 tested serological groups of meningococci, gonococci and 4 nonpathogenic Neisseria species. The possible role of these structures as common Neisseria antigen in the formation of natural resistance to meningococcal infection is discussed.

[A common meningococcaL intergroup antigen: immunological and immunochemical study]. / Obshchii mezhgruppovoi antigen meningokokka: immunologicheskoe i immunokhimicheskoe izuchenie.

Protein-containing preparations forming 1 precipitation line in highly sensitive immunoelectrophoretic tests have been obtained from the culture fluid of meningococci, groups A, C and X. The preparations have been found to render a very high degree of protection to mice challenged with meningococci of the homologous serogroup and a sufficiently high degree of protection to those challenged with meningococci of the heterologous serogroups. After the repeated injection of the preparations the appearance of the booster effect has been registered. Immunochemical study has shown that the preparation is a stable complex consisting of protein, group-specific polysaccharide and a heat-resistant component common for serogroups A, C, X and Y.