Vol 49, No 2 (2004)

The detection frequency of antibodies to Hepatitis E Virus (HEV) was studied in residents of the South and of the Middle European Part of the Russia Federation as well as of Siberia. Antibodies to HEV were most often found both in patients with hepatic pathologies and in subjects with diseases unrelated with a primary hepatic lesion, in particular, in patients with skin and venereal diseases and with HEV. A higher concentration of antibodies to HEV was noted also in blood donors, medical personnel and isolated communities, like prisons or psychiatric clinics. A correlation was established between the rate antibodies to HEV are registered and such risk factor as contacting with blood or a gross violation of the hygienic rules.

Reproduction of the Ebola strains (ES) virus causing lethality in guinea pigs as well as in peritoneal macrophages and aorta explants of animals was investigated in vitro and in vivo; besides, production of interferon-y (IFN-y) and of tumor necrosis factor-a (TNF-a) by macrophages and endotheliocytes of guinea pigs was also studied. The interplay "macrophage - ES" by the example of 2 models of susceptibility to ES demonstrates that the ES lethality is not unambiguously related only with a level of virus reproduction in macrophages. The interplay "endotheliocyte - ES" is indicative of that the ES lethality is inversely dependent on a level of production of the IFN-y and of TNF-a by endotheliocytes. In general, the Eboly fever lethality is not conditioned only by the ability or inability of ES to reproduce in macrophages and endotheliocytes; it also depends on a variety of pathogenetic factors, one of which could be the cytotoxic action of immune complexes shaping in the process of infection progression.

The dynamic hemolytic activity of complements (НАС) was investigated in blood of guinea pigs in lethal and nonlethal Ebola infection. The increasing НАС dynamic activity in the animal blood was found to correlate with the infection lethal course. НАС as observed in animals with lethal infection was sweepingly increasing after they, were infected with Ebola virus, and yet after 15 hours from the infection time the complement activity parameters topped 2-fold the basic values in 100% of guinea pigs. They began to be dropping by the end of day 1, their decrease reached, when the incubation time was over (days 3-4 after infection) the basic value, after which they continued to go down to the zero value in 2-3 days before the lethal outcome. The described phenomenon, like the phenomenon of accelerated death, was even more pronounced, when the animals were infected after a single immunization by activated Ebola virus. In case, guinea pigs were infected by a non-lethal Ebola virus strain, the compliment synthesis was observed to be activated only at the end of the incubation period; the process was accompanied with a gradual raise and with a plateau-type or wave-type increase of the complement during the treatment time - it was equally accompanied with normalizing activity parameters during recovery. The detected specificity could be important in prognosticating a disease outcome. A reliable correlation was demonstrated between the complement hemolytic activity and the level of circulating immune complexes in blood of experimental animals, which can be traced both in lethal and non-lethal infection.

Data are described in the paper on the significance of hormonal and immunological impairments and on their interrelation within the pathogenesis of herpetic keratitis in males. An evaluation of contents of testosterone, Cortisol, CD8*, CD95*lymphocytes, interleukin-6 and tumor necrosis factor-a (TNF-a) as well as definition of interrelations between them has a prognostic value for males with herpetic keratitis. A dropping concentration of testosterone as observed in males with severe herpetic keratitis is indicative of the feasibility to add some hormonecorrecting drugs to the combined therapy.

The baculovirus expression system was made use of to derive the recombinant nucleocapsid (N) proteins of the American and European virus types and of the porcine reproductive and respiratory syndrome (PRRS). The obtained products were purified by metal-affine chromatography and their specificity was confirmed in immunechemical reactions with reference monoclonal antibodies. The antigenic activity of recombinant proteins was studied by indirect immune enzyme assay (IEA) with porcine serum, which had been in advance characterized by the "HerdCheck" kit (IDEXX Co.). It was shown as possible to apply the derived recombinant antigens in determining, by indirect IEA, antibodies to the PRRS virus.

A Russian immune-enzyme test-system ("HERPES-DIAGNOST") was designed on the basis of detection of lowavidity IgG antibodies in order to promote the laboratory value of serological examinations of patients with different clinical manifestations of the herpetic infection. The key test parameters were tuned; the immunosorbent production based on antigens (herpes simplex virus - HSV), types 1 and 2, was optimized; and the concentration was chosen for the main reagent that removes the low-avidity antibodies (8 M urea solution) and .finally, the temporal and temperature regimes were selected for testing. A system was elaborated for registering and interpreting the results. The avidity index of antibodies lower than 35% was found to be a reliable criterion confirming the presence of acute primary infection triggered both by HSV-1 and by HSV-2. If there is a relapse of herpetic infection, the avidity index of antibodies can range from 30 to 45%.