[The ultrastructural characteristics of Neisseria meningitidis strains isolated in different forms of infection]. / Osobennosti ul'trastruktury shtammov Neisseria meningitidis, vydelennykh pri razlichnykh formakh infektsii.

The electron microscopic study of cell populations of the first generation of several N.meningitidis strains, isolated from humans and grown on artificial culture medium (Hottinger's serum agar) has made it possible to establish that these organisms are morphologically heterogeneous. It was manifested by the presence of 7 morphological variants of cells in their cultures (different strains have different proportions of these variants): (a) "normal" and similar to normal diplococcal variants; (b) atypically dividing cells; (c) spheroplastic forms; (d) protoplastic forms (typical and atypical); (e) variably gemmating forms; (f) microforms and (g) gigantic forms. These data are of interest for the microbiological diagnosis of meningitis.

[Electron microscopic study of the cytopathogenic action of meningococci in a continuous human amnion cell culture]. / Elektronno-mikroskopicheskoe izuchenie tsitopatogennogo deistviia meningokokkov na perevivaemuiu kul'turu kletok amniona cheloveka.

The electron-microscopic study of the interaction of meningococci with continuous human amnion cell culture F1 has revealed that this process comprises 3 stages. The study has shown that, following the adhesion of meningococci to the surface of cells F1, these cells are invaded by individual coccal forms of meningococci. In response to infection vacuoles appear in the cytoplasm of the cells. Meningococci are either phagocytosed inside these vacuoles, or their release into the intercellular space and the death of the infected by meningococci are observed. When the cells are infected by cytopathogenic strains, the infectious process results in the appearance of degenerative changes in the cells.

[Cellular ultrastructure of the meningococcus when incubated in a continuous culture of human FL-line amnion]. / Ul'trastruktura kletok meningokokka v usloviiakh inkubatsii ikh v perevivaemoi kul'ture amniona cheloveka linii FL.

Some details of the ultrastructure of several meningococcal strains having had contacts with cells in continuous human amnion cell culture FL for 6 hours to 2 days have been defined with greater precision by means of electron microscopy. The study has shown that the contact of meningococci with the tissue culture is accompanied by the appearance of meningococcal forms with the defective cell wall, similar to L-forms: spheroplast, protoplast, gigantic cells and microcells, as well as budding variants. The meningococcal variants with the defective cell wall, appearing in the cell culture, and the forms occurring (in different proportions) in "ripe" meningococcal populations developing in the culture media for a long time and isolated from a human body have been found to have no essential differences in their fine structure. These data indicate that any external influences (meningococci are highly sensitive to such influences) produce sufficiently rapid changes, similar to L-transformation, in the fine structure of these microorganisms.

[Ultrastructure of the meningococcus in logarithmic and stationary development phases]. / Ul'trastruktura meningokokka v logarifmicheskoi i statsionarnoi fazakh razvitiia.

The complex study of Neisseria meningitidis cultures A-208 in the time course of their development has disclosed that broth cultures in the logarithmic and stationary phases of their development are most valid on account of all their biological properties (the specific character of the reaction of agglutination, viability, the morphology of colonies and cells in light and electron microscopy). The use of scanning electron microscopy has made it possible to reveal bubbly endotoxin excretion in N. meningitidis and funnel-shaped depressions on their surface corresponding, probably, to nucleoid epicenters . In ultrathin sections some previously unknown features of the ultrastructure of N. meningitidis in the logarithmic and stationary phase of their development have been detected: (a) the morphological heterogeneity of N. meningitidis represented by cells of the "light" (L) and "dark" (D) types; (b) the surface structures of meningococcal cells from the cultures in the stationary phase of development show the tendency to smoothing out, which is accompanied by their sharper differentiation.

[Effect of penicillin and the habitat medium in the body of bacterial carriers on the intercellular bonds in populations of the meningococcus and pertussis microbe]. / Vliianie penitsillina i sredy obitaniia v organizme bakterionositelei na mezhkletochnye sviazi populiatsii meningokokka i kokliushnogo mikroba.

The relationship of the bacterial cells in populations and their adhesion activity is at present one of the research priorities in microbiological studies. The stimulating effect of penicillin on the development of morphologically different intercellular bonds (IB) in populations of the pertussis causative agent and first of all derivatives or evaginates of the cell wall membranes was observed. Morphologically similar systems and polytubular IB were detected in populations of meningococcal strains isolated from carriers having no signs of the disease. Correlation between the after-effect of penicillin and the presence of the causative agent in bacterial carriers was shown. Unknown systems of interlacing tubular structures not directly bound with the cells, the walls of which were single contour membranes were determined in the meningococcal populations treated with penicillin. IB were observed in the population in the form of transpopulation cords. Morphologically different IB playing the role of specialized organelles might be considered as factors of the functional unity of the bacterial population as a multicellular system.

[Various aspects of humoral immunity in meningococcal infections. II. Formation of antibodies to group A meningococci in adults with generalized meningococcal infections]. / Nekotorye aspekty gumoral'nogo immuniteta pri meningokokkovoi infektsii. Soobshchenie II. Formirovanie antitel k meningokokku gruppy A u vzroslykh bol'nykh generalizovannoi meningokokkovoi infektsiei.

Altogether 258 serum samples obtained from 102 patients with generalized meningococcal infection were studied by means of the immune bacteriolysis test and the indirect hemagglutination test. This study revealed a pronounced increase in the titer of bactericidal and hemagglutinating antibodies to group A meningococcus in the process of the disease. The dynamics and intensity of antibody formation, revealed by means of the two tests, were found to be in complete correspondence. Antibody formation was most intensive in meningitis accompanied by meningococcemia. In most cases these antibodies were found to belong to the class of IgM on account of their physico-chemical nature. The highest bactericidal activity was found in the sera with high hemagglutinin titers; the summary titers of these sera were 4-64 times higher than the titers of cystein-resistant antibodies.

[Dynamics of humoral immunity indices in patients with the generalized form of meningococcal infection]. / Dinamika pokazatelei gumoral'nogo immuniteta u bol'nykh s generalizovannoi formoi meningokokkovoi infektsii.

A possibility of using the passive hemagglutination test with meningococcus diagnostic agents of groups A and C for observing the changes in the infectious process was demonstrated. Sera of patients with generalized form of meningococcus infection showed an increase (by the 2nd--3rd week) and a rapid reduction (by the 4th week) of the specific antibodies titres to the levels seen during the first days of the disease. At the remote periods after the disease--in 2 to 5 years--hemagglutinins were revealed in the same titres as in healthy persons (1:10--1:13). Study of physico-chemical nature of antibodies demonstrated that at the early stages of meningococcus infection there formed antibodies referred chiefly to macroglobulins, and at the remote periods (after 3 months)--to microglobulins.

[Humoral immunity aspects of meningococcal infection. I. A method of performing and the characteristics of the immune bacteriolysis reaction]. / Nekotorye aspekty gumoral'nogo immuniteta pri meningokokkovoi infektsii. Soobshchenie I. Metodika postanovki i osobennosti reaktsii immunogo bakterioliza.

Immune bacteriolysis test with meningococcus, group A, was used for the purpose of serum antibody study. Meningococcus cultures with a bright orange fluorescence of the colonies in oblique illumination (the I type) proved to possess the greatest lysability. Guinea pig serum sorbed with meningococcus suspension was found to be the best source of the complement. Sera obtained after 1 to 3 days of rabbit immunization, containing mostly IgM antibodies, had the greatest bactericidal capacity. Only those fractions which contained IgM possessed bactericidal activity in the hyperimmune rabbit sera with a high IgG antibody concentration. No lytic activity was displayed against meningococcus by unfractionated hyperimmune sera.