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Corynebacterium spp. are part of the human microbiome, but can cause the development of inflammatory diseases of various localization. Purpose - to evaluate the relationship between pathogenic properties and resistance to antimicrobial drugs (AMD) of Corynebacterium spp. from patients with inflammatory diseases of the respiratory tract. Strains of Corynebacterium spp. isolated from patients with inflammatory diseases of the respiratory tract (99 pcs.) and practically healthy individuals (33 pcs.). Isolates were identified by mass spectrometric method (MALDI-ToFMS), their adhesive and invasive activity on Hep-2 cells, cytopathic effect (CPE) in CHO-K1 cell culture, and resistance to antimicrobial drugs (AMD) were determined. Indicators of adhesion (3.65±0.679(CFU±m)x102/ml), invasion (1.72±0.230 (CFU±m)x102/ml), cytotoxicity (69.1±3.8% of dead CHO-K1 cells ) Corynebasterium spp. strains isolated from patients are higher (p≤0.05) than similar indicators in practically healthy people. 90.9% of isolates from patients had resistance to AMD, in most cases (57.6±4.9%) resistance to only one AMP was noted, less often to two (25.2±4.3%), three or more (8.08±2.7%). According to the results of correlation-regression analysis, pathogenic properties (adhesiveness, invasiveness, cytotoxicity) of Corynebacterium spp. strains isolated from patients are in close direct relationship with resistance to AMD. This indicates the importance of identifying strains of non-diphtheria corynebacteria resistant to AMDs, which, under the influence of developing resistance to AMDs, can increase their pathogenic potential, moving from commensalism to parasitism., Competing Interests: The authors declare no conflict of interest.

Determination of changes in the morphostructure of microorganisms under the influence of antibiotics, disinfectants, biocins, physical and chemical agents is carried out using the method of visualization of ultrathin sections in a transmission electron microscope. The aim is to develop methodological techniques for express preparation and visualization of the ultrastructure of bacteria in a transmission electron microscope to detect structural damage to cells and assess the quality of the microbial population. A technique of accelerated sample preparation for visualization of the fine structure of bacteria and diagnosis of structural damage to cells in a transmission electron microscope has been developed. The use of this method will make it possible to more effectively investigate the mechanisms of inactivation of microorganisms at different stages of contact with antibiotics, disinfectants, biocines, including various stressful, damaging and lethal physical and chemical effects., Competing Interests: The authors declare no conflict of interest.

Corynebacterium spp. It is associated with inflammatory diseases of the respiratory tract (tracheitis, pharyngitis, rhinosinusitis, bronchitis, pneumonia, etc.). C. pseudodiphtheriticum can be the causative agent of bacterial coinfection in patients with a new coronavirus infection (COVID-19). The aim is to determine the pathogenic properties and resistance to antimicrobial drugs of Corynebacterium spp. strains to establish their etiological significance in the development of inflammatory diseases of the respiratory tract. Strains of Corynebacterium spp. isolated from patients with inflammatory diseases of the respiratory tract (43 pcs.) and practically healthy individuals (29 pcs.). Isolates were identified by mass spectrometric method (MALDI-TOF MS), their cytopathic effect in CHO-K1 cell culture, hemolytic, urease activity, antimicrobial drug resistance were determined. Strains of Corynebacterium spp. isolated from patients in the amount of 105 CFU/ml or more, practically healthy - 104 CFU/ml or less. Isolates of Corynebacterium spp. patients had a more pronounced cytopathic effect (83.7±11.1%) and were more often resistant to antimicrobial drugs than those isolated from practically healthy. To establish the etiological significance of Corynebacterium spp. isolates. in the development of inflammatory diseases of the respiratory tract, it is advisable to determine their amount in biological material (105 CFU/ml or more), the cytopathic effect on CHO-K1 cell culture, as well as the presence of multiple resistance to antimicrobial drugs. Differences in the characteristics of Corynebacterium spp. isolates. from patients with respiratory tract pathology and practically healthy individuals are associated with the strain, not the species, of corynebacteria., Competing Interests: The authors declare no conflict of interest.

In the post-epidemic period, the circulation of the causative agent of diphtheria in the population is maintained due to the carrier of bacteria. Entering an organism with a high level of antitoxic immunity, the pathogen enters into intermicrobial interactions with representatives of the opportunistic microflora inhabiting the respiratory tract and forms a biofilm., Materials and Methods: Modeling of the biofilm formation process was carried out using the strains C.diphtheriae gravis tox+№. 665, C.pseudodiphtheriticum, S.aureus. Biofilm samples were placed on the stage of a scanning electron microscope and gold-sputtered in an EicoIB-3 ioncoater vacuum deposition unit (Eico, Japan) at an ion current of 6-8 mA. The samples obtained were examined in a JEOL 6510LB scanning electronmicroscope. («JEOL» company, Japan) at an accelerating voltage of 30 kV., Results: Electron microscopic examination of samples of biofilms C. diphtheriae gravis tox+ № 665 and opportunistic microorganisms shows groups of 2-7 young bacterial cells packed into a single microcapsule. Much more voluminous accumulations of bacterial cells (more than 10-12) are typical for biofilm samples represented by C. diphtheriae gravis tox+№ 665 and S. aureus cells. On the surface of the biofilm, young bacterial cells with an intact structure are located at various stages of active division. The conglomerates of bacterial cells, covered with a common intermicrobial matrix, adhere tightly to each other and form a multilayer biofilm., Conclusion: Features of the ultrastructure of biofilms containing strains of C. diphtheriae and opportunistic bacteria, especially antibiotic-resistant bacteria inhabiting the respiratory tract, can contribute to long-term persistence of the pathogen of diphtheria in the body. They not only significantly complicate the access of antibacterial drugs, but also interfere with the isolation of C.diphtheriae during bacteriological research., Competing Interests: The authors declare no conflict of interest.

Corynebacterium spp. - representatives of the normal microflora of the human body, but their role in the development of diseases in both immunocompromised and immunocompetent patients is known. Corynebacterim spp. (C. pseudodiphtheriticum, C. striatum, C. amycolatum, C. accolens, C. argentoratense, etc.) is associated with diseases of the respiratory tract: tracheitis, pharyngitis, rhinosinusitis, bronchitis, etc. They can be transmitted by airborne droplets, household contact, and possibly by hematogenic pathways. Corynebacterim spp. toxins do not produce, but are capable of adhesion and invasion, biofilm formation, production of neuraminidase, hyaluronidase, and hemolysin. It is necessary to take into account not so much the species, but the strain affiliation of isolates of Corynebacterium spp., since among the representatives of one species of non-diphtheria corynebacteria (for example, C. pseudodiphtheriticum), colonizing the respiratory tract, there may be strains that can exhibit not only pathogenic properties, but also probiotic activity. Microbiological diagnostics is based on their quantitative determination in biological material, phenotypic (culture study, test systems for biochemical identification, Vitek 2 automated systems) and genotypic (16SpRNA gene sequencing and rpoB) methods. It is possible to use mass spectrometric analysis (MALDI-ToF-MS). The greatest activity against Corynebacterium spp. in vitro studies preserve vancomycin, teicoplanin, and linezolid. Successful therapy with at least two of the following antimicrobial agents (AMP) has been reported: vancomycin, rifampicin, linezolid, and daptomycin. The sensitivity of isolates of Corynebacterium spp. to AMP is not related to the species, but is due to strain differences, and therefore it is necessary to test each isolated strain. Continuous monitoring of the sensitivity of Corynebacterium spp. strains to AMP is necessary due to the observed variability of these traits. Of particular importance is the identification of multidrug-resistant isolates that are currently considered highly pathogenic. When compiling the review, the databases Scopus, Web of Science, The Cochrane Library, CyberLeninka, RSCI were used., Competing Interests: The authors declare no conflict of interest.

When the nasopharynx is colonized with toxigenic strains of the diphtheria pathogen, toxin is released, which contributes to the death of epithelial cells. But in bacterial carriers, the development of the clinical picture of the disease does not occur. This is due to the peculiarities of the state of their immune system, as well as the peculiarities of the production of diphtheria exotoxin by corynebacteria in the biofilm. Goal. Determining the nature of the cytopathic effect of C. diphtheriae as part of a biofilm in CHO-K1 cell culture. The planktonic and biofilm (120- and 720-hour) cultures of the strains were studied: C. diphtheriae gravis tox + № 665, C. diphtheriae gravis tox + № 6765, C. diphtheriae mitis tox + № 269, C. diphtheriae gravis tox + isolated from a patient with a diagnosis Localized oropharyngeal diphtheria C. diphtheriae gravis with a silent tox-gene. Biofilm (120- and 720-hour) cultures of diphtheria pathogen strains were obtained according to the Watnik method. The cytopathic effect of corynebacterial strains was studied on a CHO-K1 cell culture, taking into account in an inverted microscope. When studying the cytopathic effect of planktonic cultures of toxigenic strains of corynebacteria, it was found that the number of living CHO-K1 cells after 24 hours was insignificant (25.3±1.2%) and sharply decreased (2.5±0.5%) after 72 hours of cultivation. Under the influence of biofilm and, especially, 720-hour cultures, a different cytopathic effect dynamics was found: the number of living cells after 24 hours remained significant (82.5±2.2%), while at 72-hour it decreased to 25.0±3.0%. In the study of filtrates of planktonic and biofilm cultures of C. diphtheriae strain with a «silent» tox-gene, similar patterns were revealed. However, the number of live CHO-K1 cells when exposed to the filtrate of a 720-hour biofilm culture was significantly higher (p≤0.05) than when studying toxigenic strains of corynebacteria. Considering the nature of the cytopathic action, it was found that planktonic cultures of toxigenic strains of corynebacteria are characterized by a change in the cell monolayer, manifested by their thinning and elongation. The study of 720-hour biofilm cultures at 72-hour exposure revealed the appearance of a large number of rounded cells (63-69%). The cytopathic effect, formed under the influence of filtrates of planktonic and biofilm cultures of C. diphtheriae with a «silent» tox-gene, as well as strains of non-diphtheria corynebacteria, is characterized by rounding of cells and the formation of symplasts. In the biofilm, the intensity of the cytopathic effect of toxigenic C. diphtheriae strains and C. diphtheriae strain with a silent tox-gene decreased. CPD, manifested by thinning and lengthening of CHO-K1 cells, is associated with the action of diphtheria exotoxin, and rounding is associated with corynebacterial enzymes and, apparently, fragments of surface structures - adhesins. Decreased release of toxin and enzymes beyond the C. bihfilm matrix is a significant cause of the «asymptomatic» carriage of diphtheria., Competing Interests: The authors declare no conflict of interest.

As a result of the conducted researches it is shown that 44.1% of urinary tract infections (UTIS) caused by E. coli are accounted for by producers of beta-lactamase of the extended spectrum of action (ESBL). Associated resistance to fluoroquinolones and co-trimoxazole was found in 93.3% of BLRS-producing E. coli strains. All studied strains regardless of ESBL production were sensitive to imipenem, the majority showed sensitivity to ertapenem, gentamicin and resistance to doxycycline. Not producing ESBL strains of E. coli were sensitive to fosfomycin. Comparison of data obtained during testing of isolated cultures on ESBL, study of their sensitivity and resistance to beta-lactams (amoxicillin/clavulanate, ceftazidime, ceftriaxone, cefotaxime, imipenem) indicates the need to test isolates for AmpC products. To this end, during the screening test for ESBL and the method of «double disks», along with cephalosporins of III generation, it is necessary to use a phenotypic test for sensitivity to cefepime. The use of test results of E. coli isolates isolated from patients with UTIS for the production of ESBL, ampC enzymes, carbapenemase and sensitivity to AMP will improve the effectiveness of antimicrobial therapy and will help to curb the formation and spread of antimicrobial-resistan strains., Competing Interests: The authors declare no conflict of interest.

Corynebacteria non-diphtheria and, in particular, C. pseudodiphtheriticum species that are closely related to C. propinquum and C. striatum form a group of new respiratory pathogens leading to the development of bronchitis, tracheitis, exacerbation of chronic obstructive pulmonary diseases, nosocomial pneumonia and other pathology. The goal is to analyze the frequency of the release of Сorynebacteria non-diphtheria from the upper respiratory tract of patients with various inflammatory diseases of the respiratory tract. Strains of Сorynebacteria non-diphtheria (C. pseudodiphtheriticum, C. propinquum, C. accolens, et al.), isolated from patients with inflammatory diseases of the respiratory tract (60 pcs.) and practically healthy individuals (31 pcs.) were studied. Identification of Сorynebacteria was performed using the method of mass spectrometry (MALDI-ToFMS). Сorynebacteria nondiphtheria in the amount of 105 and higher were more frequently detected with the development of chronic tonsillitis (60.0%) and nasopharyngitis (30%). The strains of C. pseudodiphtheriticum (40.0±6.4%) and the closely related species C. propinquum (21.7±5.3%) were mainly found; much less often - C. accolens (8.3±3.6%), C. afermentans (6.7±3.3%), et al. In 86.7% of cases, Corynebacteria non-diphtheria were isolated from children. In chronic tonsillitis, C. pseudodiphtheriticum and the closely related species of C. propinquum were isolated more often; in nasopharyngitis and bronchitis - С. pseudodiphtheriticum. Isolation of Corynebacteria non-diphtheria and, especially, C. pseudodiphtheriticum, C. propinquum, C. accolens species from patients with inflammatory diseases of the respiratory tract in the amount of 105 and above, if there are no other pathogenic microorganisms in the role of microbial associates, of clinical importance., Competing Interests: The authors declare no conflict of interest.

The purpose of study is to determine sensibility of strains of C. diphtheriae gravis tox+ in the composition of mixed biofilms to antibacterial medications. The object of study was strains of Corynebacterium diphtheriae gravis tox+ № 665, Corynebacterium pseudodiphtheriticum (poly-resistant), Corynebacterium pseudodiphtheriticum (antibiotic-resistant). Two mixed biofilms (120- and 720-hours) of strain of Corynebacterium diphtheriae gravis tox+ № 665 with strains of Corynebacterium pseudodiphtheriticum (poly-resistant), Corynebacterium pseudodiphtheriticum (antibiotic-resistant) were formed. The sensibility of typical and biofilm cultures of Corynebacteria to antibiotic medications was established using technique of serial dilution in fluid growth medium on the basis of MPC (mg/l). The typical culture of museum strain C. diphtheriae gravis tox+ № 665, modeling mixed biofilms had a sensitivity to all used antibacterial medications. The analysis of antibiotic resistance of strain of C. diphtheriae gravis tox+ № 665 in content of biofilm with strain С. pseudodiphtheriticum, poly-resistant to four antibacterial medications (cefazolin, kanamycin, azithromycin, ciprofloxacin, IPC from 1.25±0,00 to >5±0,00 mkg/ml) set reduction (p≤0,05) sensitivity 120-hour biofilm cultures of this strain to cefazolin, azithromycin, ciprofloxacin (MIC of 0, 234 and up to ±0,11>5±0,00 ug / ml) established decreasing (p≤0,05) of sensitivity of 120-hours biofilm culture of this strain to cefazolin, azithromycin, ciprofloxacin (MIC from 0, 234±0,11 to >5±0,00 mkg/ml) and 720-hours culture - to all mentioned medications (MIC from 0,312±0,00 to >5±0,00 mkg/ml). The comparison of antibiotics resistance of biofilm cultures of strain C. diphtheriae gravis tox+ № 665 established that indices of MIC of most of antibacterial medications and especially to those that poly-resistant and forming biofilm strain С. рseudodiphtheriticum was resistant, were higher as related to biofilm cultures of diphtheritic bacteria separated from biofilm with antibiotic resistant strain С. рseudodiphtheriticum. The trend was established related to decreasing of antibiotic sensitivity of Corynebacteria at cultivation in content of mixed biofilms with representatives of opportunistic Corynebacteria having polyresistance to antibacterial medications., Competing Interests: The authors declare no conflict of interest.

Aim: Study the frequency of occurrence of antibiotics resistant strains of various species of Corynebacterium non diptheriae., Materials and Methods: C.pseudodiphtheriticum, C.pseudo- tuberculosis, C.xerosis, C.amycolatum, C.striatum, C. ulcerans strains isolated from patients with pathologies of respiratory and urogenital tract, as well as individuals taking prophylaxis ex- amination were used. Sensitivity to antibacterial preparations was determined by the serial dilution method., Results: The highest number of Coryniebacterium non diptheriae strains dis- played resistance to benzylpenicillin (54.8%) and lincomycin (50.7%), and lowest - to cefotaxime, cefazolin (6.8%) and vancomycin (13.7%). The highest number of antibiotics resistant strains were detected among members of C.pseudotuberculosis (100%), C.xerosis (96.0%) and C. pseudodiphtheriticum (81.0%) species. Polyresistant strains were detected most frequently among C.xerosis, C.amycolatum and C.striatum species. Strains of Corynebacterium non diptheriae most frequently displayed resistance to 1 or 2 antibacterial preparations (24.7%), less frequently - to 3 (20.5%); 4 (13.7%), 5 (4.1%) and 6 (1.4%) preparations., Conclusion: The amount of antibiotics resistant strains of Cdrynebacterium non diptheriae is large (89.0%) and non-similar in various species.

The purpose of study is to analyze sensitivity of various species Corynebacterium non diphtheriaе to antibacterial pharmaceuticals. The strains of C. non diphtheriae are separated from patients with pathology of respiratory and urogenital tract and also from individuals subjected to preventive examination. The sensitivity to antibacterial pharmaceuticals was determined using technique of serial dilution in fluid growth medium on the basis values of minimal inhibitory concentration (mg per l). It is established that the most efficient antibacterial pharmaceuticals in the case of strains C. non diphtheriae proved to be Vancomycin, Cefazolin and Cefotaxime in general. In case of such particular species as С. pseudodiphtheriticum -- Cefazolin, Cefotaxime and Gentamycin; С.pseudotuberculosis -- Vancomycin, Cefazolin, Cefotaxime and Gentamycin; C. xerosis -- Cefotaxime; С.striatum -- Cefazolin and и Rifampicin. The least efficiency was manifested for strains C. non diphtheriae by Benzylpenicillin and Lincomycin in general. In case of such particular species as С. pseudodiphtheriticum and С. pseudotuberculosis -- Lincomycin and Erythromycin; C. xerosis and С. striatum -- Benzylpenicillin, Lincomycin and Erythromycin. In case of various species of C. non diphtheriae Сephalosporins (Cefotaxime and Cefazolin) can be recommended as pharmaceuticals of choice and Gentamycin and Vancomycin as reserve pharmaceuticals., Competing Interests: The authors declare no conflict of interest.

In a review of the features of the bacterial cells are Corynebacterium structure: characterized by an upper layer, highly organized cell wall, cytoplasmic membrane, cytoplasm, nucleoid. Described in detail the structure of the upper layer containing pili (fimbriae), microcapsule surface proteins - PS-2, DIP1281, 67-72r protein (hemagglutinin), porins, sialidase (neuraminidase). These components are the ability to initiate a serial of Corynebacterium work with the host cell, followed by colonization. It submitted a detailed description .of the structure and functions of cell wall structures - cord factor, which is a second barrier permeability; arabinogalactan, peptidoglycan, lipomannan and lipoarabinomannan. The structure and function of the cytoplasmic membrane as the main diffusion barrier cell cytoplasm and the genome of Corynebacterium. Presented differ- ent molecular genetic methods for the identification and differentiation of closely related species of Corynebacterium.

The article describes a clinical case of tuberculosis of of urinary tracts of a female patient with massive discharge of strain Corynebacterium riegelii from urogenital tract. The data of clinical laboratory examination of female patient are analyzed. The characteristics of isolated strain C. riegelii (high degree of isolation rate (106 and higher) expressed urease activity (decomposition of urease during 5 min), presence of hemolytic activity) with consideration for estimation of its antibiotics sensitivity. The etiologic significance of isolated species C. riegelii in development of infection process in urogenital tract is demonstrated., Competing Interests: The authors declare no conflict of interest.

Pathogenicity factors of Corynebacterium non diphtheriae - pili, microcapsule, cell wall, pathogenicity enzymes, toxins, that determine the ability of microorganisms to consequentially interact with epithelium of entry gates of the organism, replicate in vivo, overcome cell and hu- moral mechanisms of protection, are examined in the review. Particular attention in the paper is given to species of non-diphtheria corynebacteria, that are pathogenic for human and able to produce toxins - Corynebacterium ulcerans and Corynebacterium pseudotuberculosis. Mechanisms of expression regulation of PLD-exotoxins, its interaction with immune system cells are described.

The proper identification of Corynebacterium non diphtheriae is complicated by their wide species variety, variable biochemical activity, large spectrum of diseases at which they are isolated and also by their presence in normal human micro-flora. The bacteriological method is a traditional basis for identification of corynebacteria though long (7-14 days), produces ambiguous results at cultivation of lipophilic and biochemically variable species. For final identification of nondescript species of Corynebacterium non diphtheriae it is recommended to carry out molecular genetic study using golden standard - sequencing on 16S pRNA (DNA), genes rpoB and PLD.In case of receiving of ambiguous responses of sequencing on 16S pRNA precise identification is achieved by sequencing of secondary gene rpoB that permits discovering unique differences in sequences of genomes in different species of corynebacteria (presence of genes of virulence; absence of cluster of genes responsible for production of number of saccharolytic enzymes; presence of genes coding synthesis of particular pigments, etc.). The mass-spectrometric analysis (MALDI-ToF-MS) applied for screening identification of Corynebacterium, is simple in implementation, though requires further development for more accurate differentiation of closely-related species. The poly-phase approach to identification of Corynebacterium non diphtheriae is needed which is to include chemotaxonomic, phenotypic, genotypic information required for reliable description of new clinically significant species of corynebacteria.

The comparative analysis was carried out concerning effectiveness of three techniques of identification of Corynebacterium non diphtheriae: bacteriological, molecular genetic (sequenation on 16SpRNA) andmass-spectrometric (MALDI-ToFMS). The analysis covered 49 strains of Corynebacterium non diphtheriae (C.pseudodiphheriticum, C.amycolatum, C.propinquum, C.falsenii) and 2 strains of Corynebacterium diphtheriae isolated under various pathology form urogenital tract and upper respiratory ways. The corinbacteria were identified using bacteriologic technique, sequenation on 16SpRNA and mass-spectrometric technique (MALDIToF MS). The full concordance of results of species' identification was marked in 26 (51%) of strains of Corynebacterium non diphtheriae at using three analysis techniques; in 43 (84.3%) strains--at comparison of bacteriologic technique with sequenation on 16S pRNA and in 29 (57%)--at mass-spectrometric analysis and sequenation on 16S pRNA. The bacteriologic technique is effective for identification of Corynebacterium diphtheriae. The precise establishment of species belonging of corynebacteria with variable biochemical characteristics the molecular genetic technique of analysis is to be applied. The mass-spectrometric technique (MALDI-ToF MS) requires further renewal of data bases for identifying larger spectrum of representatives of genus Corynebacterium.

The Rostovskii state medical university of Minzdrav of Russia, 344022 Rostov-on-Don, Russia The analysis is applied concerning significance of laboratory techniques of verification of streptococcus infection (bacteriological analysis, detection of anti-streptolysin O in pair serums) in 148 patients with infectious mononucleosis aged from 3 to 15 years. The content of anti-streptolysin O exceeded standard in 41 ± 4.8% of patients with concomitant in acute period and in 49.5 ± 4.9% during period of re-convalescence. This data differed from analogous indicator in patients with negative result of examination on streptococcus infection independently of period of disease (9.3 ± 2.8%). The exceeding of standard of anti-streptolysin O was detected more frequently (t ≥ 2, P ≥ 95%) in patients with isolation of Streptococcus pyogenes (56.9 ± 5.8%) than in patients with Streptococcus viridans (31.2 ± 6.5%). The concentration of anti-streptolysin 0 in patients with concomitant streptococcus infection varied within limits 200-1800 IE/ml. The minimal level of anti-streptolysin O (C = 200 IE/mI) was detected independently of type of isolated Streptococcus and period of disease. The high levels of anti-streptolysin O were observed exclusively in patients with isolation of Streptococcus pyogenes. In blood serum ofpatient with concomitant streptococcus infection (Streptococcus pyogenes + Streptococcus viridans) increasing of level of anti-streptolysin O was detected in dynamics of diseases from minimal (C = 200 IE/ ml) to moderately high (200 < C < 400 IE/mI). It is demonstrated that to identify streptococcus infection in patients with infectious mononucleosis the anamnesis data is to be considered. The complex bacteriological and serological examination ofpatients is to be implemented This is necessary for early detection ofpatients with streptococcus infection and decreasing risk of formation of streptococcus carrier state.

Aim: Study the structure of homogenous microbial communities of Corynebacterium diphtheriae gravis tox+ strains during formation of biofilms in vitro., Materials and Methods: Object of study--typical and biofilm cultures of C. diphtheriae gravis tox+ museum and circulating strains. Intensity of biofilm formation was evaluated by OD on microplate reader at 540 nm wave length studying 120 and 720 hour cultures. S-450 (Hitachi, Japan) scanning electron microscope was used., Results: The peak of exopolysaccharide matrix (EPS) formation, that is formed in the process of biofilm formation, by museum strain takes place at earlier terms of cultivation (120 hours) than circulating (720 hours). An inverse correlation was established during analysis of bacterial cells of museum and circulating strains of C. diphtheriae during biofilm formation between them and intensity of EPS formation. At maximum EPS content, that took place at various terms of cultivation of the 2 studied strains of diphtheria causative agent, a reduction of corynebacteria cells was observed., Conclusion: Bacterial biofilms of museum and circulating strains of C. diphtheriae and patterns of dynamics of EPS reflect, probably, adaptive abilities of the causative agent, that determine its competitiveness in the fight for adhesion sites, resistance to factors of natural immunity and as a result--prolonged persistence in the organism of bacterial carriers.

Aim: Study apoptogenic activity of-microbes-associants during Epstein-Barr virus infection (EBVI) on the model of mice peritoneal macrophages in vitro., Materials and Methods: Evaluation of apoptosis induced by bacteria isolated from EBVI patients was carried out by characteristic morphological changes of macrophages in smears stained by May-Grunwald with additional staining by Romanowsky-Giemsa., Results: All the EBVI microbes-associants were established to have apoptogenic activity, however, the highest pathogenic potential was noted in Streptococcus pyogenes., Conclusion: The presence of apoptogenic activity in bacterial microflora accompanying EBVI against immune system cells could serve as means of their survival and be the pathogenetic basis for prolonged persistence in the organism.

Aim: Determine the ability of Corynebacterium non diphtheriae to induce phagocytosis and apoptosis of macrophages and evaluate regulatory effect of nuetrophilokines (NPK) induced by Corynebacterium non diphtheriae on these processes., Materials and Methods: The ability of Corynebacterium non diphtheriae, isolated from upper respiratory tract, skin and urogenital tract (UGT) were studied for the ability to induce phagocytosis and apoptosis of mice macrophages (MP; in vitro during staining by May-Grunwald with additional staining by Romanowsky-Giemsa) before and after the addition of NPK induced by Corynebacterium non diphtheriae., Results: Phagocytic index (PI) was the same for all the Corynebacterium non diphtheriae species, phagocytic number (PN) and index of phagocytosis completion (IPC)--were minimal relative to corynebacteria isolated from UGT. All the studied corynebacteria species induced MP apoptosis; the most pronounced apoptogenic effect was detected in Corynebacterium pseudotuberculosis isolated from UGT. NPK increased PN against corynebacteria isolated from the studied biotopes, IPC--only during studies of corynebacteria isolated from skin. The effect of NPK resulted in a reduction of apoptogenic effect for almost all the Corynebacterium non diphtheriae, regardless of the isolation location., Conclusion: A pronounced apoptogenic effect and insufficiency of phagocytosis processes induced by corynebacteria are the means of realization of Corynebacterium non diphtheriae pathogenic effect. NPK use is possible for immune correction of immune deficiency conditions developing against the background of diseases determined by Corynebacterium non diphtheriae.

The article discusses presence of typical characteristics of parameters of system immunity under gonococcal and nonspecific uretroprostatitis and diagnostic value of these indicators. The reliable differences of immunologic indicators in patients with gonorrhea are established as compared to patients with nonspecific bacterial uretroprostatitis. The study established in peripheral blood the reliable decrease of level of leukocytes, relative amount of monocytes, phagocyte index, functional reserve of leukocytes at the expense of spontaneous and stimulated NBT test, IgA, sIgA. On the contrary, the study detected increasing of level of IgM and lactoferrin in patients with gonorrhea as compared to corresponding indicators in patients nonspecific infections. Under gonorrhea, the largest deviation of indicators from standard values was established for lactoferrin. The detected differences of immunologic parameters can be used as differentiating markers of nonspecific and gonococcal uretroprostatitis and criteria of effectiveness of immune correction.

The paper is devoted to the study of surface structures including pili (fimbriae) 67-72p surface protein, DIP 1281 surface protein, lipoarabinomannan CdiLAM and their role in the adhesion and colonization of the mucous membrane of the throat by Corynebacterium diphtheriae. A description is offered for the main stages in the adhesion process of diphtheria causative agent and the ability of its adhesins to stimulate the effect of innate and acquired immunity factors. The paper stresses prospectiveness of the development of vaccines forming immunoprotection of the organism against adhesive activity of C. diphtheriae and also preventing their colonization and reproduction. That would facilitate a solution for the problem of diphtheria carrier state, which cannot be solved using the existing means of preventive vaccination.

Aim: Study the mechanisms of formation of cell and humoral immunity against pertussis, diphtheria and tetanus in children immunized with immunobiological preparations (APDT vaccine and ADT anatoxin)., Materials and Methods: 30 practically healthy children (6 - 9 years of age) immunized with APDT and ADT-M preparations had TLR2, TLR4 expression determined in mononuclear cells (MNC). Vaccine preparations (APDT, ADT-M, AD-M, AT) and Corynebacterium diphtheriae gravis tox+, C. diphtheriae mitis tox- and Bordetella pertussis 345 were used as ligands. Cytokine production was determined in EIA. Content of anti-diphtheria, anti-tetanus and anti-pertussis antibodies--by PHA reaction and EIA., Results: During stimulation with vaccines and B. pertussis 345 strain MNC were characterized by an increase (p < 0.05) of expression level of TLR2 and TLR4 and did not respond to stimulation with C. diphtheriae gravis tox+ and C. diphtheriae mitis tox- strains. Similar results were obtained during study of cytokine production (TNFalpha, IL-1, IL-6). A direct correlation between levels of antitoxic antibodies against diphtheria and tetanus (R = 0.486), antibacterial antibodies against pertussis and diphtheria was detected (R = 0.529)., Conclusion: Analysis of cytokine production profile and determination of surface TLR expression can be used during evaluation of functional status of innate immunity cells and intensity of post-vaccinal immunity.

The article deals with results of studying diphtheria causative agent capacities to form biofilm as one of mechanisms of persistence in human organism. The study object was strain of C.diphtheriae gravis tox+ obtained from nasopharynx of patient aged 19 in municipal hospital No 1 of town of Gukovo of Rostov oblast in 2011. The patient had diagnosis of "diphtheria of nasopharynx, typical filmy, localized, mild severity, even course". The control was implemented using the museum strain C.diphtheriae gravis tox+ No 665 from the L.A. Tarasevitch state research institute of standardization and biologic preparations control. It is established that diphtheria causative agent as an ability to form biofilm. The intensity of process of formation of exopolysaccharide is higher on glass that on plastic surfaces. The differences in degree of intensity of formation of biofilm are revealed between the strain circulation in population and museum strains C.diphtheriae gravis tox+. The vital capacity of biofilm forming microorganisms is related with adaptation possibilities of strains.

The article deals with the results of study of sensitivity of strains of Corinebacterium non diphtheriae circulating in Rostov-on-Don and Rostov oblast to antibacterial preparations. The strains of Corinebacterium non diphtheriae isolated from urogenital tract (C. xerosis, C. pseudotuberculosis. C. amycolatum, C. striatum) are analyzed. The sample of 41 strains of C. non diphtheriae was used to detect the sensitivity to 9 antibacterial preparations. The technique of serial dilutions in liquid growth medium was applied. The range of variations (minimal suppressive concentration) of preparations as related to C. non diphtheriae made up 0.003-20.0 mkg/ ml. The results demonstrated that C. non diphtheriae are: highly sensitive to gentamycin, vancomycin and cefotaxime: sensitive to rifampicinum; and resistant to lincomicyn. In all analyzed strains of Corinebacterium non diphtheriae the greatest indicators of minimal suppressive concentration are detected in lincomicyn and at that the maximal indicator was for C. striatum and consisted 11.52 +/- 2.26 mkg/ml.

Aim: Study the possibility of resistance increase of macrophages of experimental animals to apoptogenic effect of pertussis preparations with neutrophilokines., Materials and Methods: Apoptosis was evaluated in Coulter flow cytofluorimeter after staining with propidium iodide, as well as by characteristic morphologic changes in cells stained by histological preparations and by DNA fragmentation., Results: The studies performed showed that pertussis preparations cause apoptosis of peritoneal macrophages leading to their alteration. Neutrophilokines induced by pertussis preparations were also established to suppress macrophage apoptosis., Conclusion: The results of our studies indicate the possibility to use neutrophilokines for immunocorrection of macrophage apoptosis induced by pertussis preparations.

Aim: Study of the apoptogenic effect of Corynebacterium diphtheriae toxigenic strains on mice peritoneal macrophages in vitro., Materials and Methods: Evaluation ofapoptosis induced by Corynebacterium diphtheriae, Corynebacterium pseudodiphtheriticum, Staphylococcus aureus, Streptococcus pyogenes strains was performed by characteristic morphological changes in macrophages in smears stained by azure eosin by Romanovsky-Giemsa., Results: Apoptogenic activity of diphtheria infectious agent was established to be determined by diphtheria exotoxin at early (after 1 hour) and surface structures and pathogenicity enzymes at later (3 hours) stages of effect., Conclusion: The ability of diphtheria infectious agent to cause macrophage apoptosis is one of the mechanisms of realization of its pathogenic properties determined by the effect of diphtheria exotoxin, as well as its surface structures and pathogenicity enzymes. The increase of apoptogenic activity of toxigenic strains of C. diphtheriae in association with S. pyogenes may be a pathogenetic base of formation of prolonged forms of bacteria carriage against the background of chronic ENT pathology.

Aim: Study of anti-diphtheria and anti-tetanus immunity in women in early postpartum period depending on age., Materials and Methods: Women in early postpartum period (n =139) with unknown vaccine anamnesis aged 17 to 44 years and under the supervision of Rostov-on-Don maternity hospital No. 2 were examined for the evaluation of the anti-diphtheria and anti-tetanus immunity state., Results: All the women had high level of protection form these infections. The level of anti-tetanus immunity intensity in the examined was higher than anti-diphtheria., Conclusion: Monitoring of anti-diphtheria and anti-tetanus immunity in women of childbearing age is necessary to resolve the issue of vaccine administration in this group. High level of maternal immunity intensity will allow to form a sufficient protection from infectious agents in neonates.

Aim: Selection of optimal tests for pertussis formulations (PF) cytotoxicity evaluation using mononuclear phagocytes model cells., Materials and Methods: A cellular pertussis vaccine, pertussis dialysated antigen and pertussis dialysated antigen fraction 2 cytotoxicity evaluation was performed by using primary mice peritoneal macrophage culture and human monocyte-like cell line U937., Results: Mononuclear phagocytes are a simple, sensitive and easily accessible model for PF cytotoxicity evaluation. The results of analysis are available within 6 hours., Conclusion: This model may be recommended as screening test for detection of PF toxicity.

To define the likelihood of development of adverse reactions and complications due to vaccination, the authors conducted clinical and laboratory studies of 115 children aged 1 to 15 years with chronic pathology (allergic diseases, pyelonephritis, immunodeficiency states), vaccinated with diphtheria and tetanus toxoids and pertussis vaccine and diphtheria and tetanus-M anatoxin and revaccinated with diphtheria and tetanus-M anatoxin. The results of the study suggested the prognostic value of allergic reaction indicators (total IgE, DA- and CA-specific IgE, vaccine sensitization detected by the basophil degranulation test) against adverse events and complications of immunization. Vaccination in children with chronic pathology in the presence of higher parameters of allergic reactions, by using hyposensitization therapy, was followed by to the formation of tense antidiphtheria and antitetanus immunity. The given data support the immunological efficiency and safety of immunization of children with chronic diseases against diphtheria and tetanus provided that hyposensitization therapy is performed, by keeping in mind the results of prior clinical and laboratory studies.

Enzyme immunoassay for determining salivary anti-diphtheria antibacterial IgA was developed to evaluate local anti-diphtheria immunity. One hundred and thirty-one apparently healthy preschool and school children aged 2 to 16 years, inoculated with diphtheria and tetanus toxoids and pertussis and attenuated diphtheria and tetanus toxoid vaccines by the immunization schedules. The apparently healthy children's saliva were found to have anti-diphtheria antibacterial sIgA, the mean content of which in the examinees aged 2-16 years was 49.4 +/- 3.0 units/ml and depended on age. The level of antibacterial anti-diphtheria sIgA significantly increased in children by age 7-9 years and unchanged by 16 years of age. Comparison of sIgA levels in children with diphtheria morbidity could identify 2-6-year-old children as a diphtheria infection risk group.

Aim: To study the magnitute of antitoxic immunity against diphtheria in different age groups of Rostov-on-Don city and Rostov region population., Materials and Methods: Antitoxic immunity against diphtheriawas studied in children 3 - 15 years old (661 persons) and adults 16 - 59 y.o. (893 persons), which were tested during 2003 - 2007 using direct hemagglutination assay manufactured by Mechnikov Scientific Production Association "Biomed" (Moscow)., Results: Proportion of children 3 - 15 y.o. seropositive to diphtheria was 98.6 +/- 0.5%. Children aged 3 years and 4 - 6 years were identified as a risk group for diphtheria as they had highest proportions of non-immune persons. Proportion of immune to diphtheria in adults was 94.4 +/- 0.8%. Maximal level of protection was observed in personsaged 16 - 17and 18 - 19 years, in which the proportion of seropositive persons was 99.1 - 100%. Persons > or = 50 years old formed group of risk because persons with low or moderate titers of antitoxin were identified in this age group mostly., Conclusion: Obtained results provide evidence on enough high level of protection of Rostov-on-Don cityand Rostov region population against diphtheria. Group of increased risk comprised of persons aged 3 - 6 years and > or = 50 years.

Aim: To study the ability of polyoxydonium (PO) to influence on adhesive properties of C. diphtheriae., Materials and Methods: Ability of PO to influence on adhesive properties of toxigenic and nontoxigenic strains of C. diphtheriae isolated from patients, carriers, contact persons as well as from healthy persons during prophylactic examinations of population in Rostov-on-Don and Rostov region was studied., Results: It was established that addition of PO in cultivation medium always suppressed adhesive activity of C. diphtheriae. In experiments on breaking of adhesion the blocking effect of PO on adhesive characteristics of bacteria had dose-dependent pattern and was pronounced when PO was used in concentration of 1200 mcg/ml., Conclusion: Obtained data prove that PO has marked antiadhesive activity against both toxigenic and nontoxigenic strains of C. diphtheriae, which could be used for the treatment of diphtheria infection.

State-of-the-art data about mechanisms of immune response against diphtheria are presented. Antitoxic and antibacterial immunity as well as factors of natural resistance are characterized. Allergic and autoimmune reactions during diphtheria and their role in the development of complications are reviewed. Literature data and results of authors' studies in area of immunity against diphtheria are included in the review.

Main pathogenic characteristics (toxin production, tox-gene detection, adhesiveness) of 59 strains of C. diphtheriae circulating in Rostov-on-Don city and Rostov region in 2004-2005 were studied. Study of toxigenicity of 15 tox+ C.di phtheriae strains showed full coincidence of Elek immunoprecipitation test and polymerase chain reaction (PCR). Presence of part of A-fragment of tox-gene was detected in 5 (11.4%) of 44 C. diphtheriae strains that were negative in Elek test. Hemagglutinating activity of toxin producing strains was intermediate (40%) or high (60%). Among non-toxigenic strains those with intermediate adhesiveness were predominated (45,5%), the intermediate or high adhesiveness was detected in strains positive in PCR. Obtained characteristics of C. diphtheriae can be useful for surveillance for diphtheria infection during interepidemic period.

Antidiphtheria immunity in children aged 3-15 years was evaluated, depending on their age, the vaccinal preparation chosen for immunization and the immunization schedule. Adsorbed DPT vaccine was shown to have a higher immunological activity in comparison with adsorbed DT toxoid with reduced antigen content. The relationship between the tension of antidiphtheria antitoxic immunity in children and the possibility of the formation of the clinical forms of diphtheria with different severity in the patients was established. Children aged 4-6 years were considered to be a group of high risk in diphtheria morbidity, as it was among the children of this group that toxic and subtoxic forms of diphtheria were most often registered (44.9 +/- 7.1% of the examinees); in addition, a high proportion of children seronegative to this infection (26,3 +/- 2.2%) was observed in this group.

As found in this study, the development of the manifest forms of diphtheria occurred in the presence of lower levels of antitoxic antibodies, than bacterial carrier state. The level of antitoxic antibodies in all patients, irrespective of the time of their examination, was higher than that of antibacterial antibodies. In the dynamics of the disease a considerable increase in antitoxic and antibacterial antibodies was observed in localized and disseminated forms of diphtheria and, to a considerably lesser degree, in toxic and subtoxic forms of diphtheria, while not observed in the process of the formation of bacterial carrier state. The dynamics of a rise in the levels of antitoxic and antibacterial antibodies in the manifest forms of diphtheria infection made it possible to differentiate between the cases of toxigenic Corynebacterium diphtheriae carrier state and those of the disease.

The comparative study of immune response after immunization of adults with adsorbed DT toxoid with reduced antigen content and Imovax-DT-adulte vaccine, as well as the safety of these preparations, was made. The study revealed that immunization of adults with adsorbed DT toxoid having reduced antigen content, made in two injections, and the injection of Imovax-DT-dulte vaccine, as well as the successive injection of these preparations, produced the same the levels of antitetanus immunity. Antidiphtheria immunity, evaluated by the number of seroconverted to diphtheria persons following two injections immunization was similar for the two preparations, while the level of antidiphtheria antibodies was higher in persons immunized with adsorbed DT toxoid. The immune stratum index was rather high among persons aged 16-29 years. This age group exhibited the highest number of persons, seropositive to both diphtheria and tetanus. Both vaccine preparations, adsorbed DT toxoid with reduced antigen content and Imovax-DT-adulte vaccine, were found to be equally capable of inducing autoimmune reactions in the vaccinees, detected by laboratory methods.