The article presents the results of a long-term study of biological and genetic stability of tick-borne encephalitis strain 205 which is used by the FSUE «SPA «Microgen» to produce tick-borne encephalitis vaccines EnceVir (for adults) and EnceVir Neo for children, both of which are tissue cultured, inactivated, purified, and sorbed. The biological stability of strain 205 was studied at the seed lot stage using passages on outbred white mice: initial production strain 205 and production «stock strain». Lyophilisates of production seed lots were studied at different storage intervals at -20 °С (up to 9 years of storage and more). Biological activity parameters (tick-borne encephalitis virus (TBEV) titre in log LD 50 /ml) were studied by using different ways of infecting outbred white mice, and strain 205 identification (specificity) was determined by comparing it to a reference strain in a biological neutralization assay (BNA) according to the manufacturer’s specifications for the vaccines concerned. The same materials and a batch of TBEV vaccine produced from the production «stock strain» (lyophilisate of 1986) were analyzed by polymerase chain reaction (PCR) and sequencing for genetic stability during passaging and long-term storage. The results of the study made it possible to demonstrate the biological and genetic stability of strain 205 during production of TBEV vaccines.

The purpose of the present investigation was to comparatively evaluate the performance characteristics of the test systems designed to verify the positive results of screening survey for HIV infection, such as the solid-phase immunoassay DS-EIA-HIV-AB/AG-SPECTR (Diagnosticheskiye Sistemy (Diagnostic Systems) Research-and-Production Association, Nizhni Novgorod) and tests based on immune blotting (IB). The investigation examined 15 seroconversion panels produced by ZeptoMetrix (USA) and BBI (USA). The use of the DS-EIA-HIV-AB/AG-SPECTR test system determined 88 of the 167 seroconversion panels as HIV positive. The IB-based tests revealed only 45 of the 167 samples as positive. Consequently, the application of the DS-EIA-HIV-AB/AG-SPECTR test system is more effective than the IB-based tests in early HIV infection.

Vitaherpavac, a dry inactivated herpes simplex virus (HSV) culture vaccine, has been obtained, by using the Vero B continuous cell line as a substrate for accumulation of herpes simplex virus types 1 (US strain) and 2 (VN strain). Vitaherpavac and the similar vaccine Herpovax made by the Research Institute of Vaccines and Sera, Saint Petersburg (for which preparation a primary trypsinized chick embryo cell culture used as a substrate for accumulation of HSV types 1 and 2), underwent comparative clinical trials. The tolerability and therapeutic effectiveness of the vaccine were tested in patients diagnosed as having chronic frequently recurring herpes. The trials have yielded positive results that suggest that it is expedient to introduce of the new vaccine Vitaherpavac into practice to treat chronic recurrent herpetic infection of various localizations. Vitaherpavac has been registered in the Russian Federation and permitted for medical application.

Some parameters of hemostasis and cytokine production during the fatal and nonfatal course of experimental human versus murine infection caused by Dengue virus (DV) were studied. Its lethal dose administration induced a rapid development of anemia, thrombocytopenia and a change in packed cell volume. These changes were not so profound in the nonfatal group of infected mice. There was an excess production of both proinflammatory (TNF-alpha, IL-1beta) and anti-inflammatory (IL-6, IL-10) cytokines in the fatal group. In mice of this group, the early rise of IFN-gamma and IL-12 corresponded to the parameters observed in patients with severe forms of DV infection. The findings provide evidence that the proposed model may be used for the experimental study of the immunopathogenesis of the disease.

The quality of drugs used in the Russian Federation to prevent and diagnose tick-borne encephalitis (TBE) was analyzed. The TBE vaccines made in Russian were shown to be as effective as those manufactured in foreign countries and to have the similar production techniques and quality indices therefore they may be interchangeable in the population's vaccination. The specific activity of has recently increased in terms of the content of TBE virus antibodies. In Russia, a wide range of enzyme immunoassay systems have been designed and manufactured for the detection of human serum (plasma) IgM and IgG antibodies to TVE virus and for that of TBE viral antigen in the biological objects, primarily in the ticks.

The high rate of tick-borne encephalitis (TBE) morbidity is lasting for recent years in many areas of Russian Federation. Vac- cination with TBE vaccine is considered to be most effective mean of TBE prophylaxis in endemic areas. VIRION branch (in Tomsk) of MICROGEN State Company have been producing inactivated TBE vaccines for more than 40 years. Since 2001 VIRION have been producing and selling novel purified concentrated TBE vaccine EnceVir. Vaccine EnceVir contains inactivated TBE virus of Far Eastern subtype as active substance with high level of its purity. The vaccine substantiated high level of immuno- genicy and safety in adult and children clinical trials. Postmarketing surveillance during 2001—2005 has verified these conclusions. Hence EnceVir is effective, safe and most available regarding value vaccine for mass vaccination campaign in Russian Federation.

The paper deals with an investigation of an immune response in BALB/c mice immunized with tick-borne encephalitis (TBE) vaccine and infected with TBE virus and in non-immunized mice. The parameters of specific humoral (IgG and IgM) and cellular (gamma-interferon (IFN) and cell proliferation) immunities and the activity of cytokines (necrosis tumor factor-alpha, interleukin (IL)-1beta, IL-2, IL-6, IL-10, and IL-12) were studied. There were significant differences in the specific and nonspecific immune response of immunized and non-immunized animals. Noteworthy is the difference in the time course of changes in the levels of IL-6, IL-2, IL-12, and gamma-IFN in the immunized and non-immunized animals.

A preclinical trial of the vaccine HIVREPOL provided a complex of methods for assessing the identity and specific activity of vaccines against HIVIAIDS. The identity of "HIVREPOL" has been assessed by indirect enzyme immunoassay (EIA): the vaccine specifically binds the antibodies of the sera from HIV-infected individuals. Immune blot assay was the most informative method for assessing the identity of the candidate vaccine. The sera from HIVREPOL-vaccinated mice recognized the proteins gp41, p24, p55 of cultured HIV1 on "New-Lay-Blot1" strips. The bands corresponding to p24 were revealed in the line blots "Blot-HIV-1/2+O" and "INNO-LIA-HIV-Confirmation". The specific activity of the HIVREPOL vaccine was confirmed from the reactivity of sera of the mice vaccinated with recombinant proteins of the immunosorbents available in EIA test systems for the detection of HIV antibodies. Competitive EIA established the antigen-binding activity of sera from HIVREPOL-vaccinated mice against the native reference HIV-1 antigen.

Three foreign and one Russian ELISA test-systems for detection of IgM to Borrelia burgdorferi sensu lato were comparatively studied with the use of the clinical material in an encoded experiment. In the foreign ELISA test-systems based on the use of native antigens of borrelia, cross reactions with sera from patients with syphilis, Epstein-Barr infection, cytomegalovirus infection and systemic lupus erythematosus were detected. The Russian recombinant ELISA test-system Borreliosis-ELISA-IgM showed high sensitivity and specificity. The simultaneous use of the test-systems for detecting IgG and IgM significantly increased the efficacy of diagnosis of early borreliosis.

Four foreign and one Russian 1st generation test-systems for detecting class G antibodies or summary antibodies to Borrelia burkdorferi sensu lato were comparitively investigated with the use of the clinical material under conditions of an encoded experiment. Cross reactions with sera from patients with syphilis, Epstein-Barr infection, cytomegalovirus infection and systemic lupus erythematosus were observed. The best specificity and sensitivity parameters were provided by the Enzygnost Borreliosis test-system.

One foreign and two Russian recombinant enzyme immunoassay test-systems were comparatively investigated under conditions of an encoded experiment. Sensitivity in the experiment with the Russian test-systems Borreliosis-ELISA-IgG and Lyme Best was 63.8 and 68.8% respectively. As for the test-system Borrelia IgG Recombinant, it was 47.5%. All the test-systems were highly specific (94.4 to 99.5%). The test-systems Lyme Best and Borrelia IgG Recombinant revealed partial cross reactions with sera from patients with systemic lupus erythematosus and leptospirosis.