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Extensive spread of tick-borne diseases poses a significant problem for public health and the health of the population living in endemic areas.The aim of the study was to search, analyze genetic material and identify new viral agents of the Phenuiviridae family in taiga ticks collected in Asian regions of Russia using the method of high throughput sequencing.Materials and methods. The study involved 1460 taiga ticks collected in suburban areas of the Tomsk, Yekaterinburg and Primorsky Territory. The genetic material isolated from ticks was sequenced using Illumina technology followed by phylogenetic analysis.Results and discussion. Analysis of the sequencing results made it possible to detect extended nucleotide sequences of the L-gene fragment characteristic of the Phenuiviridae family viruses. We were able to identify 20 nucleotide sequences the length of 250 bp on average in homogenates of Ixodes persulcatus ticks. Eighteen isolates have been identified as members of the genus Uukuvirus and two isolates have been assigned to the genus Phlebovirus, Phenuiviridae family. Phylogenetic analysis has shown that all isolates of the genus Uukuvirus fall under the cluster of Tacheng tick virus 2 belonging to the species Tacheng uukuvirus. They form a separate phylogenetic group which is closely related to two Romanian variants of 2019. Tacheng tick virus 2 was detected in all three surveyed regions of the Asian part of Russia. Two Tomsk isolates of phlebovirus were classified as Sara tick phlebovirus and they clustered with two isolates of phleboviruses from Karelia. Thus, the genetic material of Tacheng tick virus 2 and Sara tick phlebovirus belonging to two genera of the family Phenuiviridae was found in I. persulcatus ticks collected in three geographically different regions of the Asian part of Russia.

Introduction. Kindia tick virus (KITV) is a novel segmented unclassified flavi-like virus of the Flaviviridae family. This virus is associated with ixodes ticks and is potentially pathogenic to humans. The main goal of this work was to search for structural motifs of viral polypeptides and to develop a 3D-structure for viral proteins of the flavi-like KITV. Materials and methods. The complete genome sequences for KITV, Zika, dengue, Japanese encephalitis, West Nile and yellow fever viruses were retrieved from GenBank. Bioinformatics analysis was performed using the different software packages. Results. Analysis of the KITV structural proteins showed that they have no analogues among currently known viral proteins. Spatial models of NS3 and NS5 KITV proteins have been obtained. These models had a high level of topological similarity to the tick-borne encephalitis and dengue viral proteins. The methyltransferase and RNA-dependent RNA-polymerase domains were found in the NS5 KITV. The latter was represented by fingers, palm and thumb subdomains, and motifs A-F. The helicase domain and its main structural motifs IVI were identified in NS3 KITV. However, the protease domain typical of NS3 flaviviruses was not detected. The highly conserved amino acid motives were detected in the NS3 and NS5 KITV. Also, eight amino acid substitutions characteristic of KITV/2018/1 and KITV/2018/2 were detected, five of them being localized in alpha-helix and three in loops of nonstructural proteins. Conclusion. Nonstructural proteins of KITV have structural and functional similarities with unsegmented flaviviruses. This confirms their possible evolutionary and taxonomic relationships.

The south of Western Siberia traditionally belongs to the regions with unfavorable epidemiological situation for tick-transmitted infections. In Novosibirsk and its suburbs, approximately 20 thousand people annually seek for medical care after tick bites. The purpose of this work was to determine human-attacking tick species composition in the territory of Novosibirsk and its suburbs by identifying nucleotide sequence of tick mitochondrial gene cytochrome oxidase COI fragment during the 2018 spring-summer season, determination of infections of individual ticks with viral and bacterial tick-borne infections, followed by genotyping identified pathogens by PCR methods, by determining nucleotide sequences and phylogenetic analysis. It is established that ticks of five species attack the humans: Ixodes persulcatus, Ixodes pavlovskyi, Dermacentor reticulatus, Dermacentor marginatus, Dermacentor nuttali in the Novosibirsk metropolis. The majority of tick attacks on humans are associated with I. pavlovskyi (43.6%) and D. reticulatus (41.2%) ticks. The genetic material of the tick-borne encephalitis virus was detected in 3.6%, borrelia 13.8% and Rickettsia 23.1% individual ticks collected from humans. Genotyping of the tick-borne encephalitis virus (TBEV) in the collected ticks showed the presence of TBEV Siberian and Far Eastern genotype in 83% and 17% cases, respectively. The Kemerovo virus could not be detected. Genetic material from Borrelia spp. and Rickettsia spp. has been detected in all five tick species attacking the local human population. The bulk of the identified Borrelia spp. isolates were genotyped as Borrelia garinii (86%) and 13% of the isolates as Borrelia afzelii species. The genetic material of Borrelia miyamotoi was found in one individual tick. Ticks of the genus Dermacentor have been found to be infected by Rickettsia raoultii, and ticks of the genus Ixodes were largely infected with Rickettsia tarasevichiae, and I. persulcatus tick was infected by Rickettsia helvetica in a single case. Thus, the human population of Novosibirsk and its suburbs is attacked by five species of ixodid ticks dominated by I. pavlovskyi and D. reticulatus ticks. The genetic material of the following tick-borne pathogens was found: Siberian and Far Eastern TBEV genotype, B. garinii, B. afzelii, B. miyamotoi, R. raoulti, R. tarasevichiae and R. helvetica in the individual ticks collected from humans.

Mucosal immunity is realized through a structural and functional system called mucose-associated lymphoid tissue (MALT). MALT is subdivided into parts (clusters) depending on their anatomical location, but they all have a similar structure: mucus layer, epithelial tissue, lamina propria and lymphoid follicles. Plasma cells of MALT produce a unique type of immunoglobulins, IgA, which have the ability to polymerize. In mucosal immunization, the predominant form of IgA is a secretory dimer, sIgA, which is concentrated in large quantities in the mucosa. Mucosal IgA acts as a first line of defense and neutralizes viruses efficiently at the portal of entry, preventing infection of epithelial cells and generalization of infection. To date, several mucosal antiviral vaccines have been licensed, which include attenuated strains of the corresponding viruses: poliomyelitis, influenza, and rotavirus. Despite the tremendous success of these vaccines, in particular, in the eradication of poliomyelitis, significant disadvantages of using attenuated viral strains in their composition are the risk of reactogenicity and the possibility of reversion to a virulent strain during vaccination. Nevertheless, it is mucosal vaccination, which mimics a natural infection, is able to induce a fast and effective immune response and thus help prevent and possibly stop outbreaks of many viral infections. Currently, a number of intranasal vaccines based on a new vector approach are successfully undergoing clinical trials. In these vaccines, the safe viral vectors are used to deliver protectively significant immunogens of pathogenic viruses. The most tested vector for intranasal vaccines is adenovirus, and the most significant immunogen is SARSCoV-2 S protein. Mucosal vector vaccines against human respiratory syncytial virus and human immunodeficiency virus type 1 based on Sendai virus, which is able to replicate asymptomatically in cells of bronchial epithelium, are also being investigated.

Objective of the study was to assess the level of infection with Borrelia miyamotoi in ticks Ixodes persulcatus and Ixodes pavlovskyi collected in the south of Western Siberia.Materials and methods. 688 ticks I. persulcatus and I. pavlovskyi collected on the territory of Novosibirsk, Tomsk and Kemerovo Regions were examined. Borrelia DNA was detected by a two-round polymerase chain reaction with specifc primers to the omp66 gene region, followed by sequencing of the isolated fragments and phylogenetic analysis, including the sequences of prototype isolates published in the international GenBank database. Comparison and analysis of nucleotide sequences was carried out using the MEGA 7 software package. In parallel, the samples were examined for the presence of the agents of transmissible infections – West Nile fever and tick-borne encephalitis, anaplasmosis, ehrlichiosis, babesiosis, bartonellosis and candidate pathogens of tick-borne rickettsiosis through RT-PCR and PCR with species-specifc and genus-specifc primers.Results and discussion. The genetic material of B. miyamotoi was found in 2.2 % of I. persulcatus and I. pavlovskyi ticks in the Tomsk, Novosibirsk, and Kemerovo Regions and their appurtenance to the Asian genotype was determined. It was revealed that the degree of similarity of the omp66 gene fragments within the group of isolates of the Asian genotype was 100 %. No relation between B. miyamotoi and a specifc vector species was identifed.

Thirty nine water soluble nitroxyl radicals of various classes, belonging to piperidine, pyrrolidine and imidazolidine series were synthesized. Twenty seven of them were cytotoxic in vitro with respect to the tumor cell culture A431. The CC50 of the most active nitroxyl radicals with respect to cells SW480 and A431 was within 0.16-2.5 mM at the selectivity index of 3.91-7.81 in relation to cytotoxicity of the compounds for the cells of the normal L68 phenotype and tumor cells. The tests on the antiviral activity showed that 16 out of 22 nitroxyl radicals had antiviral activity in Vero cell culture with respect to the West Nile virus and Herpes simplex virus of type II respectively. The EC50 ranged within 0.09-3.45 mM. Some of the nitroxyl radicals had only antiviral activity, but a number of the compounds had both cytotoxic properties and antiviral activity.

Sixty preparations of basidiomycetes ( Ganoderma, Lentinus, Pleurotus, Laetiporus, Polyporus, Inonotus, Flammulina, Grifola, Trametes) were investigated with respect to their toxicity for Vero cells and antiviral activity. The antiviral activity was estimated with the use of the West Nile virus and type 2 Herpes simplex. It was shown that 11 preparations of Ganoderma, Lentinus and Pleurotus completely inhibited the infective activity in doses not lower than 1000 TCD50 (the West Nile virus) and 100 PPU (type 2 Herpes simplex). The antiviral activity of the preparations was likely due to the content of polysaccharides or their derivatives in the composition. It increased with increasing of the quantity of the total polysaccharide fraction or its concentration.

Toxicity and antiviral activity of aqueous extracts from higher mushrooms such as Lentinula edodes (Berk.) Pegler (shiitake), Pleurotus ostreatus (Jacq.) P. Kumm. (oyster), Inonotus obliquus (Ach. ex Pers.) Pilat (chaga), Hydnellum compactum (Pers.) P. Karst. (compact tooth) were studied. In doses of 0.8 to 4.0 mg (dry weight) per mouse administered orally or intraperitoneally the extracts showed no acute toxicity. When the dose of the chaga extract was increased to 20 mg per mouse, a half of the animals died. Intraperitoneal administration of the aqueous extracts in a dose of 0.4-2 mg per mouse prior to the contamination by a single LD50 of Herpes simplex type 2 provided 100-percent survival of the animals exposed to the Lentinula edodes or Pleurotus ostreatus extracts and 90-percent survival of the animals exposed to the Inonotus obliquus or Hydnellum compactum extracts.

Over the last years, an increasing rate of ixodes tick bites has been registered in the northern regions of the European Russia. In addition, the number of subjects request medical assistance due to tick bites has been dramatically increased in the Komi Republic. In addition, incidence of tick-borne encephalitis was also increased particularly starting since 2009. However, highly limited data on pathogen genetic diversity related to viral tick-borne infections in this region are currently available. Taiga ticks (Ixodespersulcatus) collected from the Komi Republic southern and central part vegetation were examined to identify and genotype tick-borne viruses. Individual ticks were used to identify by RT-PCR viral RNA coupled to tick-borne encephalitis and Kemerovo viruses. Viral genome fragment sequencing allowed to unambiguously identify these viruses. It was found that viral RNA tick-borne encephalitis was detected in 6.8±1.2% individual ticks. Moreover, tick-linked isolate genotyping based on analyzing E protein gene fragment nucleotide sequence derived from tick-borne encephalitis discovered that 35% and 65% isolates belonged to the Far Eastern and Siberian subtype, respectively. In addition, subsequent phylogenetic analysis demonstrated that at least four variants of the Siberian and Far Eastern subtypes of tick-borne encephalitis virus were detected, which were close to the viruses circulating in the Urals and Siberia. In contrast, prevalence of Kemerovo virus in taiga ticks was 0.8±0.2%. Sequencing of Kemerovo virus RNA-dependent RNA polymerase gene fragment showed around 94% homology with the remainder of the Kemerovo virus strains. Phylogenetic analysis of the Kemerovo virus genome fragments demonstrated at least two subtypes circulating in the Komi Republic. Thus, it was suggested that tick-borne encephalitis virus was introduced relatively recently from the Urals and Siberian region into the natural foci of the Komi Republic. Moreover, genetic differences found in Kemerovo virus strains presume for them a longer lasting evolution throughout the natural foci of this region. In addition, a potential role for birds and their ticks in rapid spreading of viral tick-borne infections in the Komi Republic is also discussed. Thus, the data on genetic diversity of the viral agents related to tick-born encephalitis and Kemerovo fever may be useful for improving their diagnostics, prevention and treatment in the Komi Republic.

The objectives of our study were to survey the prevalence of genetic markers for Rickettsia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., and Theileria spp. in Hyalomma anatolicum ticks collected in southwestern Tajikistan and to perform sequencing and phylogenetic analysis of fragments of the 16S rRNA gene and groESL ope-ron from Ehrlichia spp. and fragments of the 18S rRNA gene of Theileria spp. detected in H. anatolicum ticks. Hyalomma anatolicum ticks collected in the Tursunzade and Rudaki districts of Tajikistan were tested for DNA of Rickettsia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., and Theileria spp. by PCR with specific primers. The amplified fragments were sequenced and analyzed. DNA of Ehrlichia spp. (3.3 %) and Theileria spp. (3.3 %) was detected only in H. anatolicum ticks collected from the Rudaki district, and DNA of Ehrlichia spp. (0.7 %) was found in H. anatolicum ticks from the Tursunzade district. Sequence analysis of fragments of the 16S rRNA gene and groESL operon from Ehrlichia spp. revealed high similarity to Ehrlichia spp. The Tajik isolates of Theileria spp. were genotyped as Theileriaannulata based on the analysis of 18S rRNA gene sequences. The phylogenetic analysis demonstrates that Ehrlichia spp. isolates are highly similar to Ehrlichia spp. circulating in China and Brazil. The isolate Tajikistan-5 is closely related to the putative novel species Ehrlichia mineirensis. The Tajik isolates of Theileria spp. were clustered with T. annulata isolates from Turkey, Iran, Pakistan, and China by phylogenetic analyses.

The aim. Development of diagnostic kit for identifying markers of dengue fever at all stages of the disease. Materials and methods. In blood serum from patients with suspected dengue fever, NS1 antigen and specific IgM and IgG were detected by immune chromatography, dot immunoassay, enzyme-linked immunosorbent assay, using commercial test systems, as well as the “Dengue Spectrum” experimental kit. Results and discussion. A diagnostic kit has been developed for the detection of dengue fever markers, based on the mechanism of simultaneous differential detection of the agent NS1 protein and IgM and IgG class antibodies with the formation of specific complexes between markers from the test sample and known capture immune reagents, in a certain order, discretely fixed on a dense substrate. It was found that the effective detection of specific IgG and IgM to dengue virus can be carried out according to the scheme in which IgG is captured on the total antigen of the virus with detection using labeled anti-human IgG antibodies, and IgM is detected by capture on anti-human IgM antibodies with detection using total viral antigen. Detection of dengue virus NS1 protein can be performed using a substrate with immobilized monoclonal antibodies to NS1 and a gold immune sol bound to antibodies against NS1. This protocol of the dot analysis provides the limit for determining the recombinant analogue of the NS1 protein equal to 100 ng/ml. Comparative testing of the kit against the panel of clinical samples showed a good agreement between the results and the data obtained using imported commercial tests. The developed kit can be used for screening clinical samples, both in laboratory and in the field.

Introduction. The detection of the first cases of tick-borne human granulocytic anaplasmosis in Russia, discovery of genetic markers for Anaplasma spp. in ixodid ticks and reporting of a significant number of cases of tick-borne infections in the southern part of Western Siberia give reason to suppose that causative agents of tick-borne anaplasmosis may be transmitted in Tomsk and its suburbs. Objective. To study the distribution and species biodiversity of A. phagocytophilum in ixodid ticks in Tomsk Region. Materials and methods. The analysis of 690 individual ixodid ticks (larvae and adults) was carried out for Ixodes persulcatus (n = 530) and Dermacentor reticulatus (n = 160) ticks collected in 2015–2016 on the territory of urban and suburban biotopes of Tomsk. Primary screening of ticks for the presence of genetic material of A. phagocytophilum was conducted using two-round PCR with species-specific primers for the 16S rRNA gene. The amplification (1,220 kB) of the groESL fragment of the heat shock protein operon was performed for positive isolates with subsequent determination of the nucleotide sequence in the gene fragment for phylogenetic analysis. Results. The number of A. phagocytophilum positive samples for I. persulcatus (larvae) was 1.2 ± 0.6%, I. persulcatus (adult) was 1.8 ± 0.7%; and D. reticulatus (adult) was 0.6 ± 0.3%. Analysis of the nucleotide sequence of the gene fragments in groESL operon for nine isolates confirmed that the genetic material of the granulocytic anaplasmosis was detected. Phylogenetic analysis showed that all the isolates belonged to the first group of the “new cluster” of A. phagocytophilum. Conclusion. The causative agent of human granulocytic anaplasmosis has been newly detected in I. persulcatus ticks collected in urban and suburban biotopes of Tomsk and in D. reticulatus from urban foci.

Glioblastoma is a highly lethal brain cancer. Virotherapy with the use of oncolytic viruses has since recently been regarded as a promising approach for the clinic treatment of human glioblastomas. The purpose of this work was to perform a primary evaluation of the Zika virus as a potential oncolytic agent against glioblastomas. In vitro experiments showed that the Zika virus strain MR 766 is able to selectively infect and lyse neoplastic cells of the human glioblastoma cell line U87 MG. The selectivity index (SI, the ratio of infectious titer for tumor cells to titer on normal untransformed cells) was 2·102. The selectivity of the replicative activity of Zika virus in relation to U87 MG glioblastoma cells was additionally confrmed by indirect immunofluorescence. Using the model of immunodefcient SCID mice with subcutaneous xenografts of human glioblastoma U87 MG, a strong antitumor activity of the Zika virus under a course (daily for 4 days) of intratumoral administration of 5·105 TCID50 of Zika virus was shown. Treatment with Zika virus resulted in more than a 10­fold reduction in mean volumes of tumors. The tumor growth inhibition index was 92.63 %. Recurrences (metastases) of tumor re­growth were not registered within 64 days of observation. This result demonstrated the prospect of further in­depth studies of the Zika virus as a potential oncolytic agent against human glioblastomas.

Among the viruses transmitted by Chiroptera, filoviruses, lissaviruses, henipaviruses, and coronaviruses pose the major threat to humans. The featured review is devoted to the analysis of the results of studies on the role of African Chiropterans in the circulation sustenance of the viruses. Chronology of investigations on the search of natural reservoir of Filoviruses and the evidence of Chiroptera participation in their circulation are described in the paper. Presented are summarized data on the involvement of chiropterans in the circulation of lissaviruses on the African continent. Given is the information concerning the role of African species of Chiroptera in the circulation of henipaviruses - dangerous for humans viruses of Paramyxoviridae family, associated with chiropterans of South-Eastern Asia. Considered is the possibility of SARS and MERS-like coronaviruses circulation in the populations of certain species of African Chiroptera. Engagement of the Chiroptera from Guinean Republic in maintenance of circulation of the mentioned above viruses in potential natural foci in the territory of the country and possibility of occurrence of dangerous human infection outbreaks is also assessed. The necessity for further investigation of the role of Chiroptera as carriers of the stated viruses to clarify the current epidemiological and epizootiological situation on the viral pathogens in the Republic of Guinea is substantiated.

Chiroptera is one of the largest in numbers orders of mammals which can take on the role of natural host and vector of various viruses, bacteria, and pathogenic fungi. Over the period of 2007–2013, 248 new viruses pertaining to 24 families were detected in chiropterans. Lately, a range of novel infections that provoked severe diseases in humans were associated with bats-carriers. Presently they are viewed as a potential reservoir of Ebola, Marburg, and Hendra viruses, severe acute respiratory syndrome agents, as well as many other lethal diseases. Chiropterans started drawing particular attention after establishment of the fact that they are involved in circulation of ebolavirus Zaire and possibly participate in the formation of natural foci of this infection. Currently chiropterans are considered to be natural reservoirs of ebolavirus Zaire and some other filoviruses (Filoviridae). Accept from filoviruses, other significant for public healthcare viruses were isolated from chiropterans on the African continent – lyssaviruses (Rhabdoviridae, Lyssavirus), henipaviruses (Paramixoviridae, Henipavirus), and coronaviruses (Coronaviridae, Alphacoronavirus, Betacoronavirus) that can also circulate among chiropterans in West Africa. The data available from literature sources on dissemination of chiropterans in the territory of the African continent, their species diversity, peculiarities of ecology and behavior are analyzed in this paper. The information on the infections for which chiropterans can serve as potential reservoirs is also provided. Specifics of interaction between the population residing on African continent and bats of different species are described too. The review is devoted to the assessment of results of studies on population, ecological, and epidemiological factors contributing to maintenance of circulation of a number of dangerous for humans viruses (filoviruses, lyssaviruses, henipaviruses, and coronaviruses) among African chiropterans. The need for further investigation of the mentioned factors affecting chiropteran populations in the Republic of Guinea is substantiated.

The present work describes the construction of the gene encoding the recombinant protein flagG­protE, its synthesis, purification and study. The recombinant flagG­protE protein is a promising molecule for developing a candidate recombinant vaccine against tickborne encephalitis by the ability to bind to monoclonal antibodies (MCA) against native protein E of tick­borne encephalitis virus. The antigenic determinants of two recombinant proteins were studied: protE and flagG­protE using a panel of 8 MCA. The recombinant protein protE comprises the tick­borne encephalitis virus envelope protein and the flagGprotE recombinant protein has an additional flagG domain encoding flagellin G of Salmonella typhi. It was found that the MCA tested revealed epitopes on the recombinant protein protE. This indicates that the investigated recombinant protein has an antigenic structure similar to the antigenic structure of the native tick­borne encephalitis virus protein E. In the study of the recombinant protein flagG­protE by the ability to bind a panel of 8 MCA, only five of them react with epitopes of the tested protein. MCA 4F6, 7F10, and 6B9 did not recognize the corresponding epitope in the recombinant flagG­protE protein, while in the recombinant protein protE, these epitopes were detected successfully. Our data indicate that the antigenic structure of recombinant protE­protein can be changed under the influence of the flagellin domain, which in turn can lead to the unavailability of some antigenic determinants. This fact must be taken into account when constructing recombinant molecules with antigenic properties. Nevertheless, the fundamentally important regions in the region of the fusion peptide and III domain are antigenically present on the surface of the recombinant protein. This should ensure the formation of neutralizing antibodies, and the presence of a complete amino acid sequence of protein E in the recombinant protein induces the formation of a T­cell immune response. The emergence of a new generation of vaccines against tick­borne encephalitis with a higher level of safety and immunogenicity will improve the vaccine prevention of the population from tick­borne encephalitis.

Objective is to study the role of small mammals, habitant in the Republic of Guinea, in Lyssavirus circulation. Materials and methods. Investigations were conducted using RT-PCR; nucleotide sequence of Lyssavirus cDNA fragments was identified with the help of sequencing with further phylogenetic analysis. Results and conclusions. Tested have been 356 brain samples from small mammals for the presence of Lyssavirus RNA using RT-PCR with genus-specific primers. The animals were caught in the suburbs of Kindia city in 2016. The samples were obtained from wild animals pertaining to Rodentia, Chiroptera, Eulipotyphla, and Carnivora orders.Lyssavirus RNA was detected in 31 samples (8.7 %). For 14 PCR positive samples the appurtenance to Lyssavirus was confirmed through identification and analysis of nucleotide sequences of the collected short cDAN fragments of viral genome. The presence of rabies virus RNA in positive tests was excluded from PCR with the help of species specific primers. The pool of samples from black rats, Rattus rattus, positive for Lyssavirus RNA, contained RNA characteristic of Mokola lyssavirus species. Specified has been nucleotide sequence of matrix protein M gene fragment of Mokola virus. Genetic material of Mokola virus was detected in the Republic of Guinea for the first time ever.

The aim of this study was to investigate the outbreak of aseptic meningitis in theNovosibirskregion in 2008–2009. We studied genetic diversity and molecular-epidemiological characteristics of human enteroviruses that caused aseptic meningitis. Materials and metods. In the present study we investigated samples of cerebrospinal fluid from 199 patients with a diagnosis “aseptic meningitis”, based on the clinical characteristics of the disease (headache, stiff neck, fever, nausea, vomiting), and confirmed by laboratory tests of spinal fluid (lymphocyte cell count > 10 cells/ml).All samples were tested by PCR for RNA of Enterovirus and Flavivirus and DNA Myc. tuberculosis, Borrelia spp., Neisseria spp. In the samples there were not found RNA Flavivirus, DNA Myc. tuberculosis, Borrelia spp., Neisseria spp., but in 73 samples (37%) was identified RNA enterovirus (EV). Determination of nucleotide sequences of 5’UTR and VP1-region of EV revealed that they belong to the following genotypes: the highest percentage was presented by genotype ECHO 30 (62%); another genotypes were Cox A2 (8%), Cox A4 (5%), Cox A14 (3%), Cox A16 (5%), Cox B5 (8%), ECHO 6 (3%), ECHO 9 (3% ) and ECHO 25 (3%). In 2008 most of the EV that caused the symptoms of aseptic meningitis belonged to genotype ECHO 30 (76%). In 2009 the clinical specimens containing genotype ECHO 30 were not found, but the largest percentage of EV belonged to genotypes Cox A2 (33%) and Cox A4 (22%). Thus, in 2008 we recorded outbreak of aseptic meningitis, the major etiological factor was enterovirus ECHO 30. And the rise of the incidence of aseptic meningitis in 2009 is related to the circulation of new genotypes of EV. The investigated strains were deposited in an international database GenBank under accession numbers KP258231-KP258235, HM559584.

The review summarizes the literature data on the studies of viral antigens and antibodies, specific to Ebola virus, suitable for the development of a test-system for immune-diagnostics of the disease caused by them. Represented are the results of investigations on the obtainment of hybridoma monoclonal antibodies (MCA), specific to structural viral proteins NP, VP40, and VP35; recombinant proteins NP, VP40, and VP35 in prokaryotic system of E. coli; as well as the possibility to utilize MCA panels for EV viral and recombinant proteins’ detection in ELISA.

Developed has been the oligonucleotide liquid biochip based on xMAP technology, designed for the laboratory detection of particularly dangerous viral pathogens such as Ebola and Marburg filoviruses, and Machupo , Junin, and Lassa arenaviruses. The suggested approach allows for the detection of up to 100 viral genome equivalents in a sample. The sensitivity and specificity of oligonucleotide biochip is 100 % when the laboratory panels of positive and negative samples are used. These results indicate that the xMAP multiplexing for the detection and identification of tropical hemorrhagic fever agents, including Ebola virus, is not inferior to the conventional method such as real-time RT-PCR and can be applied for evaluation of viral load, and further on can easily be expanded for both the analysis of new viral agents and for the detection of critical mutations in viral genomes.

Antigenic profiles of envelope glycoproteins of hepatitis C virus presented by three genotypes 1b, 2a/2c and 3a, which are most widespread in the territory of Russia and, in particular, in Novosibirsk, were studied using a panel of overlapping synthetic peptides. It was shown that highly immunogenic peptide epitopes of Е1 and Е2 proteins common for all HCV genotypes, are located in amino acid positions 250-260, 315-325 (Е1 protein), 390-400 (hypervariable region 1), 430-440, and 680-690 (Е2 protein). The greatest inter-genotypic differences were recorded in positions 280-290, 410-430 and 520-540. A novel antigenic determinant was detected in the region of aa 280-290 of the Е1 protein which was typical only for HCV 2a/2c genotype. A broad variation in the boundaries for the most epitopes suggests a high variability of the Е1 and Е2 viral proteins; however, a similar repertoire of antibodies induced by different HCV genotypes indicates to an opportunity of designing a new generation of cross-reactive HCV vaccines based on mapping of the E1 and E2 antigenic regions.

A panel of monoclonal antibodies (MAbs) against VP35, VP40 and NP viral proteins of Marburg and Ebola viruses, as well as recombinant VP35, VP40 and NP proteins were generated and tested for their capacity to specific immune reactions. Monoclonal antibodies to appropriate viral proteins effectively recognized the VP35, VP40 and NP recombinant proteins, thus allowing to develop a variant of a MAb-based ELISA analysis with different types of biotin-labeled MAbs, using these antibodies for capturing viral and recombinant antigens of Marburg and Ebola viruses. These techniques were able to detect viral and recombinant proteins in a concentration range between 1 and 150 ng/ml. We conclude that the recombinant VP35, VP40 and NP proteins of filoviruses, as well as MAbs against these viral proteins represent a promising tool for a new generation of immunodiagnostic kits and studying immunological features of filovirus infection.

Determined is the complete genome sequence of Kolarovo-2008 strain (Siberia subtype) of Tick-borne encephalitis virus (TBEV), isolated from a tick in the suburbs of the Tomsk city. Nucleotide sequence analysis testifies of the fact that the level of genetic differences within the Siberian subtype of TBEV amounts to 10 % of the nucleotide sequence and to 7 % of amino-acid sequence for certain virus genes. 3'-HTO of the genome of Siberian subtype has the highest rate of variability and the homology level ranging from 65 to 97 %. Kolarovo-2008 and Vasilchenko (isolated in Novosibirsk in 1969) strains have the highest level of genome homology. The level of dissimilarity between the two Tomsk strains is substantially higher: the total number of amino-acid substitutions in Tomsk Zausaev and Kolarovo-2008 strains equals to 124, and 3'HTO level of homology is 79 %. Identified genetic variability of the Siberian subtype of TBEV is of a great importance for further development and enhancement of tick-borne encephalitis virus diagnostics.

Full-size genes coding matrix proteins VP40 of Ebola virus (VE) and Marburg virus (VM) and nucleoprotein (NP) of VE were cloned. These genes expression in Escherichia coli and purification of their products by affinity chromatography using Ni-NTA agarose permitted to obtain full-size recombinant VP40 and NP proteins of filoviruses. Immunological studies showed the recombinant polypeptides to possess antigenic properties similar to those of the native viral proteins. These proteins can be used for constructing of experimental vaccines against filoviruses and improving immunodiagnostic tests against filoviral infections.