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Secretory factors were isolated by lung wash followed by centrifugation to remove cells, dialysis of supernatant to remove NaCl salt, lyophilization of the lavage fluid and resuspention of the lyophilization product in an isotonic NaCl solution. It was shown that biological activity of influenza virus /Aichi/2/68 (3N2) significantly decreased (p = 0,01) from 8,17 +/- 0,10 to 7,14 +/- 0,20 IgEID50/ml during its incubation with secretory factors at 37 degrees C for 1 hr and to 7,92 +/- 0,17 IgEID50/ml in isotonic NaCl solution in the absence of these factors. Their concentration in the incubation medium was estimated to be 9.1 +/- 0.7% of their level in the lungs.

The seeding and working banks of a 4647-cell culture have been created. The 4647-cell culture in these banks has a high proliferative activity, as well as the morphology, typical of this line, and the karyotype and the enzymogram, which are characteristic for the cells of an African talapoin (Cercopithecus aethiops). The culture is not contaminated with bacteria, fungi, Mycoplasma, and viruses, including oncoviruses. The deposited 4647 cells have high viral productive properties for the accumulation of the recombinant virus strain b7,5S2-S vaccine and keep the stability of all biological properties during a long-term cultivation. The continuous 4647 cell line was tested at the L. A. Tarasevich State Institute of SK. The seeding and working banks of 4647-cell culture at passages 108 and 128 are recommended as a substrate for cultivation of the strain b7,5S2-S vaccinia, used to prepare a bivaccine against smallpox and hepatitis B.

The anticancer drug Cancerolysin has been developed, by using the mutant Adel2 variant of human adenovirus serotype 5 designed at the State Research Center of Virology and Biotechnology. Cancerolysin possesses a high degree of replication activity for complementary cells 293 and p53-deficient tumor cells and, at the same time, has significant replication limitations in normal human cells. Preclinical studies of the drug on laboratory animals (mice, rabbits, guinea pigs) have demonstrated its harmlessness and safety. When stored at -40 and -70 degrees C, the drug showed no significant activity throughout the control observational period (1 year).

Clinical trials of oral live recombinant embryonic variola and hepatitis B bivaccine as tablets (Revax-BT) were performed. When volunteers were prevaccinated with oral variola vaccine first in a small dose and, 7, 14, 30, 90, and 180 days later, in a larger dose, a slight reactoginicity was sometimes observed after the first vaccination (with a small dose) whereas revaccination with a larger dose did not give rise to any clinical manifestations. A month after vaccination, a protective level of virus-neutralizing antibodies to vaccinia virus (VV) was observed in 90-100% of the volunteers twice immunized with the bivaccine (in a small dose and in a larger one at an administration intervals of 1-2 weeks under remote revaccination while 6-9 months following vaccination, this level was recorded in 80% of the volunteers. A month following vaccination, 50-55% seroconversion to VV was observed in the volunteers twice immunized with the bivaccine (at an interval of 1 or 3-6 months). Cellular immunity to VV was low (0-20%). Double immunization of volunteers with the oral bivaccine under remote vaccination failed to produce the significant levels of humoral and cellular immune responses to hepatitis B markers. Recombinant VV was not recorded in any blood, saliva, and urine samples taken in the volunteers twice immunized with the bivaccine.

The process of the disease due to herpes simplex virus types 1 and 2 (HSV-1 and 2) was studied on white uninbred mice weighing 10 to 12 g. The animals were infected intracerebrally or intraperitoneally. Intraperitoneal contamination of the animals with MS strain of HSV-2 was used for the experimental model of the herpes simplex infection. The prophylactic antiherpes action of ultralow doses of the human gamma-interferon antibodies (ULD of anti-IFN-gamma) at a course of its intragastral administration was evaluated. The preparation was shown to have a significant (p < 0.05) protective effect in a dose of 10 LD50, evident from a 10-fold decrease of the HSV-2 accumulation in the brain, a lower percentage of the animal deaths and an increase of the average lifespan of the animals by 3.3 days. The study of the therapeutic action of ULD of anti-IFN-gamma at a course of its intragastral administration showed that the preparation had no significant positive effect on the disease process in the animals infected with HSV-2 in a dose of 10 LD50. However, a positive effect associated with delayed virus replication in the brain was observed in the study on the therapeutic effect of ULD of anti-IFN-gamma after its intragastral administration to the mice infected with a sublethal dose of the virus.

Combined application of ridostine with catonic liposomes was shown to essentially enhance the interferon-inducing and antiviral activity of the former in experiments with cell cultures L-929, which is apparently related with an improved efficiency of intracellular delivery of dsRNA. A comparative study demonstrated that ridostine, when combined with liposomes, is needed by 10(3)-10(4) times less as when it is used alone. A pretreatment of the cellular monolayer by cationic liposomes contributes also to enhancing the activity of ridostine, which can be explained by an enhanced permeability of cells for dsRNA holding on-for as long as 30 minutes after the removal of liposomes from the liquid culture. A separate successive administration of, first, liposomes and, then, of ridostine in BALB/c mice (20 mg/kg) leads to a more intensified induction of interferon in the upper respiratory tract tissues as compared with the administration of ridostine alone.

The most potent antigen among HSV-1 proteins are glycoproteins gB(UL27) and gD(US6). Multiple amino acid sequence alignment of these proteins shows that gD protein is the most specific for HSV-1. Analysis of gD protein epitopes detected the main antigenic determinants not cross-reactive with antigens of other viruses. Virus was isolated and genome DNA was prepared from morphological elements of a patient with herpes simplex infection. US6 gene fragment was cloned in pUC19 vector. Cloning in bacterial expression vectors helped obtain beta-galactosidase-fused recombinant HSV-1 gD protein with 6-histidines affine target for high-performance chromatography purification. ELISA with a set of HSV-1-positive and negative donor sera and a commercial panel of HSV-1 sera (Vektor-Best) showed that recombinant gD can be used as an antigen to HSV-1-specific IgG.

Analysis of published reports helped us single out the most potent antigens among HCMV proteins: phosphoproteins pp150(UL32) and p52(UL44). Theoretical computer analysis of p52 epitopes showed the main antigenic determinants not cross-reacting with antigens of other viruses. Virus-containing (strain AD169) material was obtained and genome DNA was isolated. Amplification of a site of gene UL44 coding for unique determinants detected a PCR fragment of required electrophoretic mobility. The fragment was cloned in vector pLBE. The specificity of cloning was confirmed by restriction analysis of theoretical sites. Nucleotide sequence of cloned fragment of UL44 gene was studied by Maxam-Gilbert's method. Cloning in expressing bacterial vectors helped obtain HCMV recombinant protein p52 in the pure form and fused with beta-galactosidase. Enzyme immunoassay with HCMV-positive and negative donor sera and ABBOTT HCMV sera showed that recombinant p52 increased the sensitivity and specificity of a previously obtained recombinant pp150 as an antigen to HCMV-IgG and HCMV-IgM. The sensitivity and specificity is 100% with 98-99% reliability.

There are known 3 likely mechanisms of virus conveyance into the central nervous system (CNS). These include hematogenic penetration, spread along the peripheral nerves, and the olfactory pathway which begins from the infected olfactory neuroepithelial cells. The possibility of viral spread into CNS via the olfactory pathway was shown for the representatives of togaviruses, herpesviruses, coronaviruses, rhabdoviruses, and for some others. This study suggests that the olfactory pathway of viral conveyance into CNS may be blocked by specific mucosal antibodies in the nasal mucosa. The recombinant TK- variant of WR vaccinia strain with inserted genes coding structural and nonstructural proteins of TBE virus is accumulated in the branches of the respiratory tract only while the parenteral vaccinia strain is detected in the brain regions, spleen, respiratory tract, and in blood. The protective activity of recombinant strain and inactivated TBE vaccine after mice immunization by escarification or intranasally, or subcutaneously was comparatively studied. The findings indicate that intranasal immunization by recombinant strain is the most protective against intraperitoneal challenge by TBE virus. The mucosal and humoral immune response that was induced by intranasal immunization seems to provide the highest levels of protection, which was experimentally observed.

The time dependence of interferon production in blood, tissues of the respiratory tract, brain and olfactory tract of mice BALB/c was investigated after administration of the interferon inductor ridostin by various routes. Intraperitoneal injection of ridostin in a dose of 5 mg/kg induced intensive accumulation of interferon in the blood serum with the peak in 8 hours (2560 U/0.2 ml) while no interferon was detected in the tissues of the respiratory tract and brain of the animals. Intracerebral injection of ridostin in the same dose induced accumulation of interferon in both the tissues of the brain (maximum 160 U/0.2 ml in 24 hours) and the blood serum (maximum 1280 U/0.2 ml in 8 hours). After respiratory administration of ridostin interferon was detected only in the site of the administration in the tissues of the upper respiratory tract and lungs of the mice.

Therapeutic and prophylactic effects of immunomodifiers ridostin, reaferon, and polyribonate used alone and in various combinations were assessed in experiments on guinea pigs infected with Venezuelan equine encephalomyelitis (VEE) (strain Trinidad), Marburg (strain Popp), and Ebola (M/C-8 variant of Zaire strain) viruses at doses 5 to 20 respiratory LD50 through the respiratory airways. Urgent prophylactic simultaneous intramuscular and intranasal administration of ridostin protected the animals infected with Marburg virus (p = 0.1) and prolonged their life span by 2.4 days (p = 0.15). In Ebola infection a combination of ridostin and reaferon appreciably prolonged the mean life span: by 2.9 days (p = 0.04). In VEE ridostin alone or in combination with reaferone appreciably increased the share of survivors; ridostin with reaferon and polyribonate notably prolonged the mean life span of infected animals. None of these drugs or combinations produced an appreciable therapeutic effect in any of the studied infections.

The investigation of the prevention and treatment action of some immunomodulators (ridostin, reaferon and polyribonate) used alone and in combinations was conducted on laboratory animals infected aerogenically by Venezuelan equine encephalitis (VEE) virus. A lower death rate of the aerogenically infected mice (10-30 respiratory LD50) was observed after intramuscular injection of ridostin. The preventive affect of ridostin and ridostin + reaferon administered intranasally and intramuscularly was achieved in the aerogenically infected guinea pigs (10 respiratory LD50). The results of the study on the early virus reproduction in the animals were used for the choice of the treatment scheme. The immunomodulators had no effect when the treatment was started 1 day after the VEE virus infection.