AIM:Study of macrophage migration inhibiting factor (MIF) effect after intracerebral administration on the course of experimental infection induced in mice by tick borne encephalitis virus (TEV), and study of sodium polyprenyl phosphate (PPP) and/or antibodies against MIF on the course of this infection against the background of MIF administration.MATERIALS AND METHODS:Phosprenil preparation was used as a source of PPP. PPP was administered intracerebrally. MIF--human recombinant (R&D, USA), mice--Balb/c line.RESULTS:In the sera of mice infected with TEV, MIF production stimulation was detected at days 8 through 10 after the infection--against the background of clinical signs presentation of tick borne encephalitis (TE). Administration of PPP to infected mice, on the contrary, resulted in MIF production suppression at the specified period. After administration of 20 ng of MIF to mice, lethality increased by 40% and average life span decreased by 2.3 days. Thus, MIF at high doses caused an increase of infection course severity, induced by TEV in mice, and administration of 60 microg of PPP resulted in the protection from infection in 100% of cases. Intracerebral administrationto mice of antibodies against MIF resulted in a decrease of lethality indicator up to 26% as compared with control and an increase of averagelife span by 5.5 days. During simultaneous administration into the brain of infected mice of MIF, PPP and antibodies against MIF, prevention of MIF-induced increase of TE course severity was registered.CONCLUSION:The data obtained allow to conclude that MIF may serve as an indicator of TE course severity, and possible prognostic indicator of meningo-encephalitic form development in humans.

Prospective anti-inflammatory activity of Phosprenyl (known veterinary drug with immunomodulating and antiviral activities) was studied using different in vitro and in vivo models. Phosprenyl exerted dose6dependent inhibitory effect on both 56lipoxigenase, and 156lipoxigenase activity. The inhibitory effect was observed even at a dose of 5 mcg/ml. Using yet another models of the hypostasis induced by the complete Freundt's adjuvant, or carraginan, we found that Phosprenyl exerted anti6inflammatory activity at both models of hypostasis, though it was weaker compared with indomethacin. In the in vivostudy Phosprenyl inoculation into mice infected with tick6born encephali6 tis virus (TBEV) led to decrease of the macrophage migration inhibitory factor (MIF) level in the blood serum, which was raised in the TBEV6infected mice. MIF inoculation into TBEV6infected mice led to the infection aggravation, while Phos6 prenyl inoculation into mice infected with TBEV, on the contrary, led to significant protection against the infection. Taking into account earlier established findings proving that Phosprenyl may function as a physiological counterregulator of MIF, a major proinflammatory cytokine, our data allow to conclude that Phosprenyl possesses anti6inflammatory activity

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.

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.

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.

Immunization with the polypeptide fragment of group A streptococcal protein M conjugated with the copolymer of acrylic acid and N-vinylpyrrolidone in complete Freund's adjuvant has been found to lead to a sharp increase in the level of antibodies to the type-specific determinants of protein M, detected in the enzyme immunoassay (EIA). The possibility of the application of such sera to preliminary typing of streptococci in EIA with the use of whole microbial cells as antigens has been shown. The data on high activity of the sera thus obtained in the bactericidal test with streptococci of the homologous type are presented. Recommendations on the use of sera obtained by the above method for highly precise typing of the virulent cultures of group A streptococci in the bactericidal test are given.

Monoclonal antibodies (MCA) D 4/1 were obtained by immunization of BALB/c mice with group A streptococci treated with pepsin. MCA D 4/1 react in ELISA test with streptococcal group A, C, L, and A-variant (V) polysaccharides (PS). D 4/1 are autoantibodies, cross-reacting in immunofluorescent test with all the epithelial layers and fibroblast-like structures of human and BALB/c mouse skin. The MCA react also with the interstitial connective tissue of human, mouse and bovine myocardium and with the fibroblast cultures explanted from the skin of donors and rheumatic patients. Tissue reactions partially inhibited purified streptococcal group A, C and L PS, however, complete inhibition was obtained only with V PS. It is suggested that MCA D 4/1 are directed to CR-antigen, common for fibroblasts, all the layers of skin epithelium and one of the rhamnose determinants of group A polysaccharide.