[Production and characterization of monoclonal antibodies to group-specific antigenic determinant of group A streptococcal polysaccharides]. / Poluchenie i kharakteristika monoklonal'nykh antitel k gruppospetsificheskoi antigennoi determinante polisakharida streptokokkov gruppy A.

Hybridomas producing monoclonal antibodies (McAb) to group A streptococcal polysaccharide (A-PS) were obtained. Of these, 3 clones were selected: 2 clones producing IgG3, precipitating McAb and 1 clone producing IgM nonprecipitating McAb. The results of the competitive inhibition in the enzyme immunoassay suggested that precipitating and nonprecipitating McAb reacted with nonidentical epitopes of A-PS, though determinants, specifically reacting with the given McAb, had a common site which included N-acetyl-D-glucosamine. On the surface of bacteria, in addition to protein M, the presence of the given determinants of A-PS was established in the direct immunofluorescence test. The newly developed method of direct immunofluorescence with the use of specially selected precipitating McAb was the basis for the development of rapid diagnosticum, permitting the identification of group A streptococci.

[Specificity of a panel of monoclonal antibodies to group A Streptococcus polysaccharide and search for cross reactions with mammalian tissues]. / Izuchenie spetsifichnosti paneli monoklonal'nykh antitel k polisakharidu streptokokkov gruppy A i poisk perekrestnykh reaktsii s tkaniiami mlekopitaiushchikh.

A panel of monoclonal antibodies (McAb) to different determinants of group A Streptococcus polysaccharide (A-PS) has been studied. As revealed in this study, A-PS contains at least 4 determinants, common with different epidermal antigens. McAb, cross-reacting (CR) with different mammalian tissue antigens, have not been found to be group-specific. Experiments on the inhibition of the immunoenzyme reaction of McAb with A-PS indicate that CR determinants include rhamnose and beta-N-acetyl-D-glucosamine of rhamnose alone. In addition, we have confirmed our earlier suggestion that group-specific high-affinity precipitating antibodies acted on different sites of A-PS. Contrary to earlier opinions, antibodies to group-specific determinants of A-PS have been found not to react with epidermal antigens.

[The structure of the determinants of streptococcal group A polysaccharide common to epidermal antigens to which antibodies are formed at different stages of the rheumatic process]. / Struktura determinant polisakharida streptokokkov gruppy A, obshchikh s antigenami epidermisa, k kotorym obrazuiutsia antitela na raznykh stadiiakh revmaticheskogo protsessa.

Several epidermal antigens containing carbohydrate determinants (DT), common with those of group A streptococcal polysaccharide (A-PS), were identified: basal-cell antigen (1), antigens of the cytoplasm (2) and perinuclear zone (3) of the cells of the differentiated epidermal layers, as well as antigen characteristic of all layers of skin epithelium (4). As shown for the first time, in addition to N-acetyl-D-glucosamine, cross-reacting DT of A-PS, antibodies to which were detected in rheumatism, also contained the remnants of rhamnose joined by bonds 1=> 2 and/or 1=>3. At the same time DT, common for A-PS and antigen 1, was found to contain N-acetylflucosamine and residues of rhamnose, joined by bond 1 reversible 2. N-acetylglucosamine was also contained in DT of A-PS, common with antigen 3. In addition, the epitopes of antigens 2 and 4, cross-reacting with A-PS, seemed to contain no N-acetylglucosamine and were characterized by some specific features of rhamnosides which they contained. It was at interest that at different stages of the rheumatism, simultaneously with autoantibodies having the same specificity, autoantibodies to different epidermal antigens were detected in the blood of patients. The determination of the spectrum of autoantibodies to epidermal antigens may be used both for diagnostic purposes and for the prognostication of the course of the rheumatism.

[The characteristics of the immune response to the polysaccharide determinants of Streptococcus group A in rheumatism]. / Osobennosti immunnogo otveta na determinanty polisakharida streptokokka gruppy A pri revmatizme.

As shown in this study, the formation of antibodies, at least, to the determinants (DT) of polysaccharide of group A streptococcus (A-PS), common with epidermal antigens, occurs in rheumatic fever. Two DT include N-acetylglucosamine; DT common with epidermal basal cell antigen (DT-1) and DT common with antigen of the perinuclear zone of the cytoplasm of cells of differentiated layers (DT-2). Two other DT seem to contain only rhamnose; DT common with the cytoplasm of cells of differentiated layers (DT-3) and DT common with epidermal antigen, characteristic of the cytoplasm of cells of all epidermal layers (DT-4). Conclusion has been made that the presence of autoantibodies to epidermal basal cell antigens, common with DT-1 and DT-4 of A-PS, may serve as an additional indicator of the activity of the rheumatic process. Autoantibodies to cross-reacting DT-4 of A-PS are indicative of the chronization of the process with a tendency to relapses of rheumatic fever.

[The effect of streptococcal group A polysaccharide on PHA-induced T-cell proliferation]. / Vliianie polisakharida streptokokka gruppy A na proliferatsiiu T-kletok, indutsirovannuiu FGA.

The influence of group A streptococcal polysaccharide (A-PS) on the proliferation and functional activity of subpopulations CD4+ and CD8+ of human peripheral blood lymphocytes has been studied. As revealed in this study, A-PS, though having no mitogenic activity of its own, is capable of influencing the process of proliferation of two main T-cell subpopulations in the presence of PHA. Its action has a regulatory character and is manifested by the maintenance of the ration of lymphocytes CD4+ and CD8+ in the culture at a constant level (approximating 1). This effect is seemingly linked with changes in the functional activity of lymphocytes in both subpopulation CD4+ and subpopulation CD8+. The detected properties of A-PS make it possible to regard it as a pathogenic factor playing an important role in immunoregulatory disturbances in diseases connected with infection caused by group A streptococcus.

[Group A streptococcal polysaccharide--an inhibitor of the functional activity of T-suppressors induced by Con A in a culture of mononuclear cells of human peripheral blood]. / Polisakharid streptokokka gruppy A--ingibitor funktsional'noi aktivnosti T-supressorov, indutsirovannykh KonA v kul'ture mononuklearnykh kletok perifericheskoi krovi cheloveka.

It was found that group A streptococcal polysaccharide (A-PS) had no mitogenic effect on the intact human blood mononuclear cells' culture (MNC) and on its proliferation stimulated with ConA. Using a double staining technique for simultaneously determining cell surface phenotype and degree of cell activation by it's ability to include the tetrazolium dye MTT (3-[4,5-dimethylthiazol-2-yl] -2,5-diphenyl tetrazolium bromide) it was established that A-PS decreased the percent of activated (MTT+) cells in the subpopulation of CD8+ and increased the percent of MTT+ cells among CD4+ lymphocytes in the intact MNC. In the MNC stimulated with ConA A-PS caused only one of these effects: it decreased the percent of MTT+ cells in the subpopulation of CD8+ lymphocytes. The correlation was established between the results obtained with MTT-technique and cell transfer test, because the MNC preincubated with ConA and A-PS lost the ability to suppresses MNC proliferation stimulated with PHA. The data obtained supported the assumption that A-PS as a carrier of determinants common with thymus epidermal antigens (factors) may act as it's functional analogue and thus promote the development of autoimmune process during the rheumatic fever.

[Lymphocytes with receptors to streptococcal polysaccharide group A in the thymus of rheumatism patients. Change in the response of normal thymocytes to adenosine, theophylline and decantate]. / Limfotsity s retseptorami k polisakharidu streptokokka gruppy A v timuse bol'nykh revmatizmom, izmenenie ikh reaktsii na adenozin, teofillin i dekantat normal'nykh timotsitov.

With the help of immunomodulators (adenosine, theophylline, levamisole) and decantat of 3-hour culture of normal thymocytes, the features of thymocytes with the receptor for polysaccharide of streptococcus group A(A-PSC) (R = PSC+cells) in patients with rheumatism. It has been established that in patients' thymus the quantity of lymphocytes, able to express R-PSC (predecessors of R = PSC + cells) decreased under the influence of theophylline and adenosine. The predecessors of R = PSC+thymocytes in the majority of patients with rheumatism are areactive to decantat action. Moreover R = PSC+cells in comparison with normal ones lose this receptors under it's influence.

[Level of antibodies to different determinants of Streptococcus group A polysaccharide and autoantibodies to basal layer of the skin epithelium in rheumatism]. / Uroven' antitel k razlichnym determinantam polisakharida streptokokka gruppy A i autoantitela k bazal'nomu sloiu épiteliia kozhi pri revmatizme.

Direct dependence was established between the presence of autoantibodies reacting with the basal layer of the skin epithelium (BLSE) and the high level of antibodies to the streptococcal group A polysaccharide (APS). By the primary active rheumatic fever (PARF) autoantibodies to the BLSE are revealed. By the recurrent active rheumatic fever (RARF) and in the control sera, autoantibodies reacting with the BLES, apparently, are directed to the rhamnose determinants of APS. These data confirm: different level of antibodies to the GS and to the rhamnose determinants of APS by PARF, RARF and in the control sera; the experiments of the autoantibody inhibition, reacting with the BLSE by the APS or the polysaccharide of streptococci A-variant, containing only the rhamnose determinants.

[Comparison of the frequency of detection of autoantibodies to epidermal antigens with the level of antibodies to polysaccharide of group A Streptococcus and the number of T-suppressors in glomerulonephritis]. / Sopostavlenie chastoty obnaruzheniia autoantitel k antigenam épidermisa s urovnem antitel k polisakharidu streptokokka gruppy A i chislom T-supressorov pri glomerulonefrite.

By the acute glomerulonephritis (GN) of streptococcal etiology, autoantibodies (AA) reacting with the basal layer of skin epithelium (BLSE) are discovered. The presence of this AA's correlate with the high level of antibodies to the streptococcal group A polysaccharide (A-PS). In the control sera such AA's and the high level antibodies to A-PS are discovered very rarely. By the GN of non-streptococcal etiology, AA's to the BLSE apparently of other specificity are obtained in some cases, in spite of the absence of antibodies to A-PS. AA's reacting with the differentiated layers of skin epithelium are discovered in the high percent of cases by GN. The presence of these AA's do not correlate with the levels of antibodies to A-PS. The reduction of the number of T-lymphocyte suppressors is established in the blood by the presence of AA's to the BLSE by GN. This question is a subject of later investigations by the different autoimmune processes. Such data can apparently corroborate the previously expressed hypothesis, that AA's to BLSE, which as a rule react with endocrine thymus epithelium, are the cause of the beginning of immunoregulatory disorders, characteristic of autoimmune processes.

[Antibodies to the rhamnose determinants of the polysaccharide of streptococci group A in the sera of rheumatism patients and donors]. / Antitela k ramnoznym determinantam polisakharida streptokokkov gruppy A v syvorotkakh bol'nykh revmatizmom i donorov.

In the sera of patients with recurrent rheumocarditis, and especially in cases of primary rheumatism, the level of antibodies to group A streptococcal polysaccharide (A-PS) has been found, according to the results of the enzyme immunoassay, to be considerably higher than in the sera of healthy donors. The level of antibodies to rhamnose determinants (RD) of A-PS has been determined by the inhibition of the immunoenzyme reaction with A-PS under the influence of a variant of group A streptococcus and rhamnose disaccharides with the bonds alpha 1-2 and alpha 1-3. In patients with recurrent rheumocarditis the level of antibodies to A-PS has been shown to be considerably higher than in healthy donors having these antibodies. In acute primary rheumatism a high level of antibodies to A-PS has been detected only in a few cases, and at the same time the prevalence of antibodies to the specific RD of A-PS, bound with beta-N-acetylglucosamine, is observed. In the sera of patients with recurrent rheumocarditis and donors having a high content of antibodies to the rhamnose site of A-PS antibodies, seemingly active against at least two RD, have been detected. In acute primary rheumatism an insignificant amount of antibodies to the rhamnose site of A-PS may probably cause the autoimmune process accompanying rheumatism. This suggestion is substantiated by the previously established capacity of these antibodies for inducing the suppression of cytotoxic cell reactions to microbial antigens.

[The suppression of delayed hypersensitivity to BCG antigens in BALB/c mice during the production of antibodies to the rhamnose determinants of Streptococcus group A polysaccharide]. / Supressiia giperchuvstvitel'nosti zamedlennogo tipa k antigenam BTsZh u myshei linii BALB/c pri produktsii antitel k ramnoznym determinantam polisakharida streptokokka gruppy A.

The data obtained for the first time in our studies indicate that the production of antibodies to group A streptococcal polysaccharide (A-PS), one of the cross-reacting streptococcal antigens, may suppress delayed hypersensitivity (DH) to microbial antigens. The existence of sharply pronounced correlation between the suppression of DH and the presence of antibodies to the rhamnose area of A-PS in the blood of BALB/c mice immunized with the pepsin-treated culture of group A streptococci has been shown. The suppression of DH is absent in the immunized animals of the same group whose blood contains antibodies to the determinant, specific for A-PS. As revealed in this study, the effect of the suppression of antigen-specific cytotoxicity linked with DH to BCG antigens can be reproduced by mixing lymph node cells taken from these two groups of the animals. The data thus obtained are possibly linked with the activation of nonspecific T suppressors in the production of antibodies to the rhamnose determinants of A-PS in the animals immunized with streptococci. The mechanism of the newly discovered phenomenon is discussed.

[Suppression of cytotoxic cellular reactions by the production of antibodies to rhamnose determinants of streptococcal group A polysaccharide cross-reacting with antigens of the skin epithelium]. / Supressiia tsitotoksicheskikh kletochnykh reaktsii pri produktsii antitel k ramnoznym determinantam polisakharida streptokokka gruppy A, perekrestno-reagiruiushchikh s antigenami épiteliia kozhi.

By the BALB/c mice after different periods of immunization with the streptococci group A, treated with pepsin, antibodies belonging to autoantibodies to the determinants (DT) of polysaccharide (A-PS), cross-reactive (CR) with the epithelial skin cells, were investigated. In one of the mice groups, in the autologous system, on the target cells--macrophages of lymph nodes, the suppression of cytotoxic (CT) reactions was obtained. The CR are bound with the delayed type hypersensitivity appearing after the sensibilization with BCG. The suppression effect correlate (z-0.95) with the presence in the sera antibodies to the rhamnose DT'S of A-PS, which cross-react with the cells of basal and superbasal layers of skin epithelium. Antibodies to the group specific of the A-PS, cross-react only with the basal skin layer and not produce the suppression of CT reactions. It is possible that they also prevent the suppression of CT reactions, bound with the CR antibodies to the rhamnose DT-S of A-PS. The obtained data corroborate the earlier supposition that the autoantibodies to the CR DT'S of A-PS reacting with the skin epithelial cells as a rule common the thymus epithelial cells. It is possible that different IRD'S can prevent or stimulate the development of autoimmune processes by the infections with the streptococci group A.

[Characteristics of cytoplasmic antigens of cells from differentiated epidermal layers in human thymic epithelium]. / Osobennosti lokalizatsii antigenov tsitoplazmy kletok differentsirovannykh sloev épidermisa v épitelii timusa cheloveka.

It was found that donor's serum and serum of patients with rheumatic fever, erysipelas and myasthenia gravis contained autoantibodies to the cytoplasmic antigens and to the antigen of perinuclear zone of differentiated layers cells of human epidermis. Using the serum with different level of autoantibodies to these epidermal antigens it's localization in the human thymus epithelium was determined. It was shown that perinuclear antigen of differentiated epidermis cells is localized in the cytoplasm of cortical and medullar thymus epithelial cells and in the perinuclear zone of some cells in Hassall's corpuscles. The cytoplasmic antigen of differentiated epidermal cells is detected only in the cytoplasm of the Hassall's corpuscle cells. The ability of many tissues (possibly all of them) and in the first turn of epidermis to produce lymphokine along with immunomodulating properties of thymus hetero-organic antigens enables to consider these thymus antigens as a complex of immunomodulating factor proper for other tissues. These factors may provide the competence of certain T-cell subpopulations to different organ's tissues necessary for proceedings them the immunological survey both in normal and pathological conditions.

[Group A streptococcal polysaccharide--stimulator of nonspecific cytotoxic reaction in autologous system of spleen cells]. / Polisakharid streptokokka gruppy A--stimuliator nespetsificheskikh tsitotoksicheskikh reaktsii v autologicheskoi sisteme kletok selezenki.

p4 was shown the ability of group A streptococcal polysaccharide (A-PS) to stimulate nonspecific cytotoxic effect of spleen cells on autologous adherent cells (macrophages). The stimulating effect can be observed in vivo under the treatment of spleen cells with A-PS and any antigen (BSA, PPD, M-protein of group A streptococci). In the presence of antigen A-PS can induce nonspecific cytotoxic effect of normal spleen cells (mice CBA, BaLB/c) and of the mice with DHT and therefore these two immunologic phenomena do not depend on each other. Because A-PS has cross-reactive (CR) determinant with thymus epithelial antigen (factor), it can be assumed that via the CR determinant A-PS links with T-cells receptor for this thymus factor and thus realized the stimulating effect as it's functional analogue.

[The effect of immunization with Streptococcus group A on the development of delayed hypersensitivity to BCG antigens in mice of different strains]. / Vliianie immunizatsii streptokokkom gruppy A na razvitie giperchuvstvitel'nosti zamedlennogo tipa k antigenam BTsG u myshei raznykh linii.

Antibodies to group A streptococcal polysaccharide (A-PS) have been shown to appear within three weeks after the injection of group A streptococcus culture, heat-killed and treated with pepsin (A-STP), in the blood of not only BALB/c mice, but also CBA mice. As revealed in this study, in BALB/c mice antibodies are mainly active against the group-specific antigenic determinant (AD) of A-PS and in CBA mice, against the rhamnose AD of A-PS, common for streptococci of different groups. This study has revealed that the appearance of antibodies to the rhamnose AD of A-PS in the blood of CBA mice inhibits antigen-specific cytotoxicity, appearing with the development of delayed hypersensitivity to BCG antigens. This effect is not linked with the immunization of the animals with high doses of streptococci. Experiments have shown that the in vitro transfer of the inhibition of antigen-specific cytotoxicity to lymph node cells of normal BCG-sensitized animals may be carried out with lymph node cells of CBA mice, immunized with A-STP and having antibodies to the rhamnose AD of A-PS, but not with the serum containing these antibodies. The mechanisms of this effect are discussed.

[Autoantibodies to different layers of epidermis during immunization of BALB/c mice with a culture of Group A Streptococcus treated with pepsin]. / Autoantitela k razlichnym sloiam épidermisa pri immunizatsii myshei linii BALB/c kul'turoi Streptokokka gruppy A, obrabotannoi pepsinom.

As revealed in the indirect immunofluorescence test, antibodies to the cross-reacting group A streptococcal polysaccharide determinant (A-PS), common to the antigen of the basal cell layer of the epidermis, regularly occur at the end of the first cycle and disappear after further immunization of BALB/c mice with the pepsin-treated culture of group A streptococci. This model may be used for the study of antibodies to A-PS, cross-reacting with the cells of the basal layer of the epidermis, in the development of the autoimmune process linked++ with group A streptococcal infection.

[Receptors for polysaccharides of group A streptococci on human thymic lymphocytes. Stimulation of their expression by action of adenosine, theophylline and supernatant of thymocytes]. / Retseptory k polisakharidu streptokokka gruppy A na limfotsitakh timusa cheloveka. Stimuliatsiia ikh ékspressii pri deistvii adenozina, teofillina i dekantata timotsitov.

It was established by indirect immunofluorescence that thymic lymphocytes bear receptors for polysaccharide of group A streptococci (Rps). The ability of thymic lymphocytes to express Rps depends on the cAMP concentration in the cell, because the treatment of thymocytes with adenosine and theophylline increases the number of cells with Rps (Tps cells). Supernatant of thymic lymphocytes is also capable of stimulating expression of Rps. Because the A-polysaccharide has common antigenic determinant with thymus epithelium antigen it can be assumed that A-polysaccharide links with the thymocytes via receptor for this epithelial antigen. This assumption needs a detailed study in view of the hypothesis about the important role of cross-reactive antigens of group A streptococci in generating autoimmune process during rheumatic fever and other streptococcal diseases. It should also be noted that Rps may be a useful marker for identification and studying the changes of Tps subpopulation in the thymus and peripheral lymphoid organs of patient with different streptococcal diseases.