Specificity of monoclonal antibodies obtained by immunization of mice with trypsin-treated group a streptococcus culture

Hybridomas producing monoclonal antibodies intensively reacting with group A streptococcus antigens in enzyme immunoassay were obtained as a result of immunizing mice with pepsin-treated cultures of group A streptococcus. All antibodies were referred to class M immunoglobulins. The reactions of monoclonal antibodies were completely inhibited by the pepsin-treated culture of group A streptococcus. The degree of inhibition with A-polysaccharide was lower, being 17.5 to 50.0 in different monoclonal antibodies. All the monoclonal antibodies obtained cross-reacted with antigens of murine and human epithelial tissues of the thymus and skin. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 492–495, November, 1994 Presented by A. G. Skavronskaya, Member of the Russian Academy of Medical Sciences     

The past,present, and future of research on the regulation of nonlymphoid cell proliferation by lymphoid cells

Reviewed are data on the capacity of T lymphocytes to stimulate or inhibit nonlymphoid cell proliferation, on the correlation of this capacity with the activity of respective immunoregulatory cells (T helpers and suppressors), and on the possible cell-mediated and humoral mechanisms through which lymphocytes execute their morphogenic function. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 230–234, September, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Effect of embryo irradiation on development of the thymus and formation of the T-lymphocyte population

Irradiation of pregnant mice causes destruction of the embryonal thymus and delays its colonization with lymphocytes, T-helper maturation, and elimination of T-lymphocyte precursors. After birth splenic colonization with lymphocytes, particularly with T helpers and T suppressors, is decresed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 416–421, April, 1994     

Formation of colonies of clonogenic stromal precursors in bone marrow and splenic cell cultures in the presence of streptococcal antigens in the culture medium

The presence of streptococcal M protein and A polysaccharide in culture medium is shown to have an inhibitory effect on the growth of clonogenic stromal precursors in cultures of healthy murine bone marrow and of healthy guinea pig bone marrow and spleen. The efficacy of colony formation dropped 1.5- to 2-fold in the presence of antigens in a concentration of 25 μg/ml in the medium. The inhibitory effect was absent if antigens were added to adhesive cell cultures. The addition of antigens to cultures originating from animals immunized with streptococcus resulted in inhibition of the efficacy of colony formation in complete cultures and in cultures of adhesive cells. The presence of streptococcal antigens in guinea pig stromal fibroblast cultures of different strains did not affect their growth or colony formation. These data indicate that the effects of streptococcal antigens appear to be aimed at the stromal cells not directly, but rather via another cellular category in the bone marrow and splenic cell cultures, probably lymphocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 489–492, November, 1994     

Size of lymphocyte subpopulations in the spleen and level of hemopoietic tissue proliferation in mice during surgical interventions

The percent and absolute content of T helpers increases in the spleen of mice 4 and 17 h after resection of the liver or removal of a kidney, which is associated with an increase of the mitotic index of splenocytes. The number of T suppressors and the bone marrow cell mitotic index are unchanged. The T-helper/T-suppressor ratio in the spleen increases 1.7–2 times during surgery on the liver and kidney. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 301–303, March, 1996 Presented by N. K. Permyakov, Member of the Russian Academy of Medical Sciences     

Participation of methylcobalamin inin vitro DNA methylation

Two DNA-methylases from nuclei of rat liver are compared for their ability to methylate thymic DNA in the presence of methyl group donors, radiolabeled³H-S-adenosyl-L-methionine and methylcobalamin. DNA-methylase with an isoelectric point of 5.2 is found, which uses both donors of methyl groups although its activity is more expressed with³H-S-adenosyl-L-methionine.³H-S-adenosyl-L-methionine and methylcobalamin presumably interact with different sites of the enzyme. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 616–618, June, 1995 Presented by T. T. Berezov, Member of the Russian Academy of Medical Sciences     

Preparation and characterization of monoclonal antibodies to group-specific antigenic determinant of group a streptococcus polysaccharide

Group A streptococcus polysaccharide contains at least two different group-specific determinants including N-acetyl-β-D-glucosamine (more important) and rhamnose. Monoclonal antibodies to group-specific determinants of group A streptococcus polysaccharide do not react with tissue antigens. Cross reactions with tissues were detected in tests with monoclonal antibodies to rhamnose-enriched epitopes of group A streptococcus polysaccharide. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 10, pp. 433–436, October, 1999     

Inhibitory effect of C-reactive protein on streptolysin O-mediated hemolytic activity. Comparison of conformational variants

It is shown that C-reactive protein binds to streptolysin O, an exotoxin of hemolytic streptococcus, and neutralizes its hemolytic activity. Incubation of C-reactive protein with the working dose of streptolysin O for 15–20 min at 37°C abolished the hemolysis of subsequently added erythrocytes. The concentration of C-reactive protein that reduced hemolysis by 50% was on average equal to 2.28±0.19 μg/ml. C-reactive protein antihemolytic activity was not affected by blocking of its phosphorylcholine-specific sites with free phosphorylcholine, but decreased as a result of blocking with pneumococcal C-polysaccharide and, particularly, with L-α-phosphatidylcholine. This indicates a hydrophobic nature of C-reactive protein-streptolysin O interaction. C-reactive protein subunits retained antihemolytic activity, while the aggregated C-reactive protein lost part of it. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5 pp. 506–509, May, 1995 Presented by A. A. Totolyan, Member of the Russian Academy of Medical Sciences     

Antioxidant and immunomodulating effects of ceruloplasmin in experimental influenza infection

Exogenous ceruloplasmin is shown to increase the resistance of mice to influenza virus, reduce the immunodepressive effect of the virus, and improve the biochemical parameters in the acute period of experimental infection. A possible positive effect of ceruloplasmin on delayed complications of influenza is discussed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 285–287, September, 1994 Presented by T. T. Berezov, Member of the Russian Academy of Medical Sciences     

Effect of chorionic gonadotropin on lactate dehydrogenase and alcohol dehydrogenase activity in the pathologically altered liver

Chorionic gonadotropin is shown to alter lactate dehydrogenase and alcohol dehydrogenase activity in the pathologically altered liver and to exert a regulatory effect on the catalytic properties of these enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 590–591, June, 1994 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Evalution of changes in secretion of active oxygen forms by polymorphonuclear lymphocytes

The increased NBT activity of leukocytes in immunized rabbits is found to be dependent on the antigen concentration and is probably related to the direct effect of antigen on the cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 163–165, February, 1994 Presented by Yu. A. Vladimirov, Member of the Russian Academy of Medical Sciences     

Formation of T lymphocytes inactivating allogeneic stem cells in the course of macrophage-thymocyte interaction

Allogeneic stem cells interact with T lymphocytes which are formed when intact thymocytes are cultured with syngeneic mononuclear phagocytes. The capacity of these T cells to inhibit the colony-stimulating activity of stem elements in endo- and exocolony formation tests is demonstrated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 298–300, March, 1996 Presented by N. N. Trapeznikov, Member of the Russian Academy of Medical Sciences     

Regulation of human natural killer activity with autologous interferon

A study is performed of the effects of α-interferon and γ-interferon induced in 8 healthy donors and 9 patients with multiple sclerosis on thein vitro cytotoxic activity of natural killers in an autologous and allogeneic systems. The general characteristics of regulation are estimated on the basis of the results. There is found to be an inhibitor regulating the effect of interferon on natural killer activity, which is produced in parallel with interferon in response to interferon induction, the efficacy of this inhibitor being dependent on the initial natural killer activity; the inhibitor is absent in commercial interferon preparations. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 281–284, September, 1994     

Effect of amiridine and tacrine on the functional degeneration of the isolated neuron

Amiridine and tacrine are found to have a concentration-dependent effect on the spontaneous activity of an isolated neuron from crawfish. Amiridine in a concentration of 1 μM reliably prolongs the lifetime of the neuron, whereas lower concentrations are inactive and a high concentration (10 μM) reduces spontaneous activity. Tacrine is unable to prolong the lifetime of the neuron. It is suggested that, unlike tacrine, the therapeutic effect of amiridine stems from its ability to prolong neuronal functioning. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 52–54, January, 1996 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Stimulation of peritoneal macrophage activity in rats with experimental peritonitis during transfusion of UV-irradiated blood

Three transfusions of blood irradiated at 254 nm induce an increase of phagocytic activity of peritoneal macrophages in rats with peritonitis in comparison with infusion of intact blood. Addition of aspirin, an inhibitor of enzymatic peroxidation of lipids, to the irradiated portion of the blood before irradiation abolishes this stimulating effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 140–142, February, 1994 Presented by Yu. A. Vladimirov, Member of the Russian Academy of Medical Sciences     

Antiopsonizing effect of extracellular staphylococcal products

The ability to inhibit the opsonizing activity of immunoglobulins and the C3 component of the complement is demonstrated forStaphylococcus aureus. This ability is due to the presence of extracellular products such as the anticomplement factor and protein A. An independent and statistically significant determination of the antiopsonizing effect of these extracellular products by the given parameters is established. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 639–641, June, 1994 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Radiometric evaluation of the effect of xenobiotics on proliferation of bone marrow cells in mice

A radiometric method of evaluating the effect of chemical compounds on the proliferative activity of bone marrow cells is described which consists of measuring the incorporation of labeled³H-thymidine in DNA. Results are reported on a comparative study of the effect of known immunotropic substances on bone marrow cell proliferation using the present method and the method of evaluating endogenous colony formation. Analysis of the results obtained by two variants ofin vivo andin vitro experiments provides additional information regarding the mechanism of action of the substances. Translated fromByulleten Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 222–224, August, 1995 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Effect of polycation based on alkaloid lupinin-antihepolin and its complex with heparin on DNA synthesis in rat hepatocytes

The effect of the antiheparinate antihepolin on the intensity of replication processes in rat hepatocytes was studied. A single intravenous infusion of polycation caused an approximately 6-fold increase in the intensity DNA synthesis on day 2 postinjection followed by a drop to thebaseline level on days 5–6. If antihepolin was injected in parallel with heparin, DNA synthesis was intensified after just 24 hours. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 627–629, June, 1994 Presented by B. T. Velichkovskii, Member of the Russian Academy of Medical Sciences     

Antiviral activity of some vasodilative preparations

The effect of no-spa, papaverine, euphylline, and nitroglycerin on reproduction of influenza viruses A and B is studied in the chorioallantois of chick embryos and in cultured canine renal cells. The optimal effect was produced by no-spa, while euphylline was somewhat less effective. Neither papaverine nor nitroglycerin had any effects on reproduction of influenza viruses A and B. The antiviral activity of no-spa has also been proven in experiments with influenza infection in white mice. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 167–169, February, 1996     

Hemispheric peculiarities of serotonin involvement in the processing of relevant and irrelevant information in mice

Stimulus-dependent hemispheric-regional changes are found in the activity of the serotoninergic system. Determination of stimulus novelty is provided by a decrease of serotonin and its metabolite content in the frontal cortex of the left hemisphere as well as in the striatum without the effect of lateralization. Presentation of an extinct stimulus is attended by a serotonin increase in the hippocampus of the left hemisphere and in the amygdaloid complex of both hemispheres. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 279–281, March, 1996 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences