N V Tikunova

Institute of Chemical Biology and Fundamental Medicine, Novo-Nikolaevsk, Novosibirsk, Russia

Are you N V Tikunova?

Claim your profile

Publications (66)43.56 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The efficiency of several mouse monoclonal antibodies (mAbs) specific to the tick-borne encephalitis virus (TBEV) glycoprotein E in post-exposure prophylaxis was assessed, and mAb14D5 was shown to be the most active of all those studied. It was proven that the hybridoma cell line 14D5 produced one immunoglobulin H chain and two L chains. They were used to construct chimeric antibodies ch14D5a and ch14D5b, the affinity constants of which were 2.6×10(10)M(-1) and 1.0×10(7)M(-1), respectively, according to the SPR-based ProteOn biosensor assay. The neutralization index (IC50) of ch14D5a was 0.04μg/ml in the focus reduction neutralization test. In in vivo experiments, ch14D5a at a dose of 10μg/mouse resulted in a 100% survival of the mice infected with 240 LD50 of TBEV. This chimeric antibody is promising for further development of prevention and therapeutic drugs against TBEV.
    Vaccine. 05/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Complete genome sequences of previously unstudied human astrovirus subgenotypes - HAstV-2a and HAstV-2c - and two isolates of a rare genotype HAstV-4 have been determined. These isolates were recovered from fecal samples of young children hospitalized with acute intestinal infections in Novosibirsk (Russia). Three of the four sequenced isolates (HAstV-2a, HAstV-2c, and HAstV-4) are recombinants. It has been shown that all known HAstV-2 genomes have emerged via recombination; the HAstV-1 and HAstV-4 genotypes contain both recombinant and non-recombinant isolates; and all HAstV-3, HAstV-5, and HAstV-6 whole-genome sequences display no reliable signs of recombination. The average mutation accumulation rate has been determined based on an extended ORF2 fragment and amounts to 1.0×10(-3) substitutions per site per year. The evolutionary chronology of current HAstV genotypes has been reconstructed.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 01/2014; · 3.22 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Whole genome sequencing of Novosibirsk human bocavirus (HBoV) isolates has detected an isolate that emerged via recombination between HBoV3 and HBoV4 genotypes. The recombination site is located between regions with abnormally low and abnormally high GC contents in the genome. This site is a bocavirus recombination hotspot and coincides with one of two parvovirus recombination hotspots. The Novosibirsk recombinant isolate, which is similar to a previously studied isolate from Thailand, utilizes the strategy of borrowing ORF3, which encodes structural proteins, of a rare genotype HBoV4. The role of recombination in HBoV evolution is discussed.
    Infection, Genetics and Evolution. 01/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Штамм энтеровируса Коксаки В6, селективно инфицирующий и лизирующий опухолевые клетки человека in vitro и депонированный в Государственной коллекции Роспотребнадзора возбудителей вирусных инфекций и риккетсиозов Федерального бюджетного учреждения науки Государственный научный центр вирусологии и биотехнологии «Вектор» под регистрационным номером V-576.
    Ref. No: 2496873, Year: 10/2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: Silver nanoparticles possess antibacterial effect for various bacteria; however mechanisms of the interaction between Ag-NPs and bacterial cells remain unclear. The aim of our study was to obtain direct evidence of Ag-NPs penetration into cells of Gram-negative bacterium S. typhimurium and Gram-positive bacterium S. aureus, and to study cell responses to Ag-NPs. The Ag-NPs (most 8-10 nm) were obtained by gas-jet method. S. typhimurium (7.81 × 10(7) CFU), or S. aureus (8.96 × 10(7) CFU) were treated by Ag-NPs (0.05 mg/l of silver) in orbital shaker at 190 rpm, 37 °C. Bacteria were sampled at 0.5, 1, 1.5, 2, 5 and 23 h of the incubation for transmission electron microscopy of ultrathin sections. The Ag-NPs adsorbed on outer membrane of S. typhimurium and cell wall of S. auereus; penetrated and accumulated in cells without aggregation and damaging of neighboring cytoplasm. In cells of S. aureus Ag-NPs bound with DNA fibers. Cell responses to Ag-NPs differed morphologically in S. typhimurium and S. aureus, and mainly were presented by damage of cell structures. The cytoplasm of S. aureus became amorphous, while S. typhimurium showed lumping and lysis of cytoplasm which led to formation of "empty" cells. Other difference was fast change of cell shape in S. typhimurium, and late deformation of S. aureus cells. The obtained results showed how different could be responses induced by the same NPs in relatively simple prokaryotic cells. Evidently, Ag-NPs directly interact with macromolecular structures of living cells and are exert an active influence on their metabolism.
    Biology of Metals 05/2013; · 3.17 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Human bocavirus (HBoV) is associated with acute gastroenteritis in humans, occurring mostly in young children and elderly people. Four bocavirus genotypes (HBoV1-HBoV4) have been found so far. Since there were no data on the contribution of HBoV to gastroenteritis in Russia, 1781 fecal samples collected from infants hospitalized with acute gastroenteritis in Novosibirsk, Russia during one year were tested for the presence of nucleic acids from HBoV and three major gastrointestinal viruses (rotavirus A, norovirus II, and astrovirus). HBoV was detected only in 1.9% of the samples: HBoV1 was detected in 0.6% and HBoV2, in 1.3%. Complete genome sequencing of three Novosibirsk isolates was performed. An evolutionary analysis of these sequences and the available sequences of human and great apes bocaviruses demonstrated that the current HBoV genotypes diverged comparatively recently, about 60-300 years ago. The independent evolution of bocaviruses from chimpanzees and gorillas commenced at the same time period. This suggests that these isolates of great apes bocaviruses belong to separate genotypes within the species of human bocavirus, which is actually the primate bocavirus. The rate of mutation accumulation in the genome of primate bocaviruses has been estimated as approximately 9×10(-4) substitutions/site/year. It has been demonstrated that HBoV1 diverged from the ancestor common with chimpanzee bocavirus approximately 60-80 years ago, while HBoV4 separated from great apes bocaviruses about 200-300 years ago. The hypothesis postulating independent evolution of HBoV1 and HBoV4 genotypes from primate bocaviruses has been proposed.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 01/2013; · 3.22 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The objective. To determine various bacterial and viral causative agents of acute enteric infections (AEI) in hospitalized adults and to genotype the obtained isolated of viral pathogens. Patients and methods. Molecular and mictobiological methods were used to examine stool samples from 100 adult patients with AEI hospitalized in 2009 to CCH No 1 of Novosibirsk, for the presence of viral (human rota-, noro-, astro-, entero- and bocaviruses) and bacterial (Salmonella spp., Shigella spp., Escherichia coli, Staphylococcus spp., Klebsiella spp.) agents. Rotaviruses of group A were genotyped by the method of multiplex PCR. For genotyping other enteropathogenic viruses the appropriate variable gene segments were sequenced. Results. The studied microorganisms were found in 57% of patients: in 23% - bacteria, in 24% - viruses, in 10% - bacteria and viruses simultaneously. The most frequently Salmonella spp. (19%) and genotypes GII.4 and GII.3 noroviruses (15%) were detected. In 7%, group А rotavirus genotypes G1P [8], G2P [4], G3P [8], G4P [8], in 3% -genotype 1 astroviruses, also in 3% -Shigella spp were found. In single cases, group С rotavirus and genotype 6 astrovirus were detected. Conclusion. As is shown, viral and bacterial agents are detected in stools of adult patients with diarrhea with the approximately equal incidence - 23-24%.
    Infections Diseases (Moscow, Russia). 01/2013; 11(2):31-37.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Anti-cytokine autoantibodies (auto-Abs) are ubiquitous both in patients suffering from infectious, inflammatory and autoimmune diseases and in healthy individuals. Particularly anti-IFN-γ auto-Abs are shown to be elevated in blood of multiple sclerosis (MS) patients.OBJECTIVE: The aim of present study was to investigate whether repertoires of anti-IFN-γ auto-Abs differ in MS patients and healthy donors. Using phage display technique we have compared repertoires of the genes encoding anti-IFN-γ single-chain variable fragments selected from MS and naïve phage display libraries.RESULTS: The panel of anti-IFN-γ auto-Abs selected from MS library includes (i) 'fetal' auto-Abs, encoded by the V _{H} 6-1 gene segment and the combination proximal D segments with distal J _{H} segments; (ii) naïve auto-Abs; (iii) affinity maturated antibodies; and (iv) abnormal single-domain antibodies. Meanwhile, the panel of anti-IFN-γ auto-Abs selected from naïve library mainly contains the naïve antibodies. Moreover, the overall antibody repertoire of MS library is skewed compared to the overall repertoire of naïve library and also contained the antibodies carrying a 'fetal' V _{H} 6 domain and the ratio of κ and λ chains was reversed. These results suggest existence of a special mechanism or trigger that provides for reconstitution of the immune system in MS.
    Human antibodies 01/2013; 22(1):31-49.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Human astrovirus is one of the etiological agents of acute gastroenteritis in humans, mostly in young children and elderly people. Complete genome sequencing of four human astrovirus strains isolated in Novosibirsk, Russia was performed. Analysis of these sequences and the sequences available in GenBank database has detected numerous potential recombination breakpoints. For the first time the rate of human astrovirus evolution was estimated based on the genome fragments without recombination breakpoints; the determined rate is typical of the RNA viruses with high evolutionary rate, amounting to approximately 3.7 × 10(-3) nucleotide substitutions per site per year, and for the synonymous changes, 2.8 × 10(-3) nucleotide substitutions per site per year.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 03/2012; 12(2):435-42. · 3.22 Impact Factor
  • Source
    Infection Genetics and Evolution 02/2012; · 2.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Genetic analysis of group A rotavirus recovered from fecal samples of children admitted to hospitals in Novosibirsk and Omsk during four epidemic seasons 2007, 2007/2008, 2009/2010, 2010/2011 was performed. A total of 1416 rotavirus isolates were genotyped using multiplex PCR. The isolates of the most common rotavirus genotypes G1P[8], G4P[8], G2P[4], G3P[8] co-circulated in Western Siberia during 2007-2011. In isolated cases G9P[8], G2P[8], G3P[9], and G4P[6] genotypes were detected. Change of dominant genotype from G1P[8] to G4P[8] occurred in 2008 in Omsk and in Novosibirsk in 2009 as well. Incidence and distribution of rotavirus genotypes differed and changed every epidemic season in both cities. The phylogenetic analysis based on VP4 (VP8*), VP7, and VP6 gene sequences showed that the majority of isolates from Novosibirsk and Omsk were clustered together and demonstrated high level homology with rotavirus isolates found in other regions of Eurasia. In addition, a rare P[8]b (OP354-like) subtype of the VP4 gene was identified in fourteen isolates (G9, G1, and G4) in Novosibirsk and in a single isolate Omsk08-381/G9P[8]b in Omsk. The results obtained in this study demonstrate the necessity of long-term monitoring of rotavirus isolates in Western Siberia. This is important for selection of rotavirus vaccine for immunization of infants, improvement of diagnostic kits and understanding of the epidemiology and the evolution of group A rotaviruses
    Molecular Genetics Microbiology and Virology 01/2012; · 0.27 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The growing body of knowledge concerning the molecular biology of viruses and virus-cell interactions provides possibilities to use viruses as a tool in an effort to treat malignant tumors. As a rule, tumor cells are highly sensitive to viruses, which can be used in cancer therapy. At the same time, the application of viral oncolysis in cancer treatment requires that the highest possible safety be ensured for both the patient and environment. Human enteroviruses are a convenient source for obtaining oncolytic virus strains, since many of them are nonpathogenic for humans or cause mild disease. The current progress in genetic engineering enables the development of attenuated enterovirus variants characterized with high safety and selectivity. This review focuses on the main members of the Enterovirus genus, such as ECHO, coxsackievirus, and vaccine strains of poliovirus as a promising source for the development of oncolytic agents applicable for cancer therapy. We have summarized the data concerning recently developed and tested oncolytic variants of enteroviruses and discusses the perspectives of their application in cancer therapy, as well as problems associated with their improvement and practical use.
    Molekuliarnaia biologiia 01/2012; 46(5):639-650.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A panel of recombinant human antibodies to orthopoxviruses was isolated from a combinatorial phage display library of human scFv antibodies constructed from the Vh and Vl genes cloned from the peripheral blood lymphocytes of Vaccinia virus (VACV) immune donors. Plaque-reduction neutralization tests showed that seven selected phage-displaying scFv antibodies (pdAbs) neutralized both CPXV and VACV, and five of them neutralized Monkeypox virus (MPXV). Western blot analysis of VACV and CPXV proteins demonstrated that seven neutralizing antibodies recognized a 35 kDa protein. To identify this target protein, we produced a recombinant J3L protein of CPXV and showed that all the selected neutralizing antibodies recognized this protein. Neutralizing pdAb b9 was converted into fully human mAb b9 (fh b9), and scFv b9 displayed high binding affinities (K(d) of 0.7 and 3.2 nM). The fh b9 reduced VACV plaque formation in a dose-dependent manner.
    Virus Research 09/2011; 163(1):141-50. · 2.75 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Six unique phage antibodies against human tumor necrosis factor (TNF) were selected from the earlier constructed naïve combinatorial library of single-chain antibodies by affinity selection. The TNF binding of these antibodies was examined by enzyme immunoassay and Western blot analysis. The specificity of the selected antibodies was determined from their binding to interferons alpha and gamma, bovine serum albumin, ovalbumin, and ubiquitin. Two antibodies (sA1 and sB3) were converted into a soluble single-chain antibodies as individual molecules. Their affinity proved to be 2.5 and 13.7 nM, respectively.
    Russian Journal of Bioorganic Chemistry 01/2011; 37(3):298-306. · 0.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Twenty unique phage antibodies to human tumor necrosis factor alpha were selected from a naive combinatorial library of human single chain fragment variable. Analysis of gene segments encoding selected antibodies shown that repertoire of variable domains of heavy and light chains included variable domains of both naive autoantibodies and antibodies produced as a result of somatic hypermutagenesis.
    Molekuliarnaia biologiia 01/2011; 45(1):96-107.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A total of 1107 fecal samples from young children admitted to hospital for acute enteric infection in January to December 2007 were tested for astroviruses. Astroviruses were detected in 64 (5.8%) of the 1107 stool samples, only 50% of them were found as monoinfections. Astroviruses were recorded throughout the year; however, no seasonality for this infection could be ascertained. Cases of astrovirus infection were mainly observed in infants under one year of age (90%). Astroviruses were typed sequencing the ORF2 fragment; only HAstV-1 and HAstV-2 were found in Novosibirsk.
    Voprosy virusologii 11/2010; 55(6):19-23.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Two chimeric antibodies (ch) 13D6 and 10C2 against the glycoprotein E of tick-borne encephalitis virus (TBEV) were constructed by fusing variable regions of murine monoclonal antibodies (Mabs) 13D6 and 10C2 to human constant regions. Monovalent analogues of these antibodies in format of single-chain antibodies (scFv or sc) were developed, as well. The ch13D6, ch10C2, sc13D6 and sc10C2 exhibited binding characteristics similar to parental Mabs. Only the ch13D6 and sc13D6 were able to neutralize TBEV infectivity in vitro. The in vitro neutralization provided by ch13D6 suggests that this antibody can be further developed into a potent prophylaxis and therapy for tick-borne encephalitis (TBE) infection.
    Vaccine 07/2010; 28(32):5265-71. · 3.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rotavirus is a genus of double-stranded RNA viruses in the family Reoviridae. Group A rotaviruses are the leading cause of acute gastroenteritis in children worldwide. The rotavirus genome consists of 11 discrete segments, encoding six structural (VP) and six non-structural (NSP) proteins. Based on the outer capsid VP4- and VP7-encoding genes, binary classification system was established for rotaviruses [1]. To date, at least 31 P and 23 G genotypes were identified. The major human rotavirus genotypes are G1, G2, G3, G4 and G9 combining with P[8], P[6] and P[4]. Since the mid-1990s there has been a global emergence of rotavirus P[8]G9 genotype. At present, 4 different phylogenetic lineages within P[8] and 6 lineages within the G9 genotype have been described based on genetic variability of the VP4 and VP7 genes [2]. In this study, we investigated rotaviruses circulating in Novosibirsk during 2003–2009. P[8]G9 was the second prevalent genotype from January 2004 to June 2006 (up to 25%). Subsequently, P[8]G9 strains were only sporadic identified from June 2007 to January 2009. The phylogenetic analysis of the partial sequences of VP4 and VP7 genes from 25 clinical isolates showed that all P[8]G9 strains grouped together within the G9-III lineage, but isolates 2004/06 clustered within the P[8]-III lineage, whereas isolates 2007/09 clustered within the P[8]-IV lineage. All other rotaviruses circulated in Novosibirsk (genotypes P[8]G1, P[8]G3 and P[8]G4) grouped only within the P[8]-III lineage. Thus P[8]G9 strains belonging to lineage P[8]-IV are the novel genetic variant of rotaviruses emerging in Novosibirsk in the middle of 2007. This study was supported by ISTC 2935.
    2nd Moscow International Conference "Molecular Phylogenetics" (MolPhy-2), Moscow, Russia; 05/2010
  • [Show abstract] [Hide abstract]
    ABSTRACT: We recently isolated and characterized a human milk peptide, lactaptin, which induced apoptosis of cultured human MCF-7 cells. Lactaptin was identified as a proteolytic fragment of human kappa-casein. Here, we generated two recombinant analogs of the peptide, RL1 and RL2, containing truncated and complete amino acid sequences of lactaptin, respectively. Analogs were produced in E.coli, purified and assayed for biological activity on cultured human MCF-7 cells. RL1 was shown to induce only a small decrease in cell viability, whereas RL2 lowered the viability of MCF-7 cells by 60%. This reduction in MCF-7 cell viability was associated with apoptosis, which was indicated by phosphatidilserine externalization and caspase-7 activation. The viability of A549 and Hep-2 cells was also reduced by RL2, albeit to a lesser degree than seen with MCF-7 cells; this reduced viability was not accompanied by apoptosis. Non-malignant human mesenchymal stem cells (MSC) were completely resistant to RL2 action.
    The Protein Journal 03/2010; 29(3):174-80. · 1.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Four unique phage single-chain variable fragments (scFvs) to recombinant human interleukin 18 (IL-18) has been selected from a naïve combinatorial library of human scFvs. Binding of unique phage antibodies with IL-18 was tested by ELISA and Western-blotting. No cross reactivity with tumor necrosis factor α, interferons α and γ was shown for the selected antibodies. The gene segments encoding V(D)J regions of selected antibodies exhibited a high degree of homology to germline genes, therefore we suggest that the selected scFv's belong to repertoire of naïve autoantibodies.
    Human antibodies 01/2010; 19(2-3):71-8.

Publication Stats

67 Citations
43.56 Total Impact Points

Institutions

  • 2011–2014
    • Institute of Chemical Biology and Fundamental Medicine
      Novo-Nikolaevsk, Novosibirsk, Russia
  • 2007–2011
    • Russian Academy of Sciences
      • Institute of Chemical Biology and Fundamental Medicine
      Moskva, Moscow, Russia
  • 1995–2010
    • State Research Center of Virology and Biotechnology VECTOR
      Novo-Nikolaevsk, Novosibirsk, Russia