Ebola fever is an acute, highly contagious viral disease with a mortality rate that can reach 90%. There are currently no licensed therapeutic agents specific to Ebola in the world. Monoclonal antibodies (MAbs) with viral-neutralizing activity and high specificity to the Ebola virus glycoprotein (EBOV GP) are considered as highly effective potential antiviral drugs. Over the past decade, nanobodies (single-domain antibodies, non-canonical camelid antibodies) have found wide use in the diagnosis and treatment of various infectious and non-infectious diseases. In this study, a panel of nanobodies specifically binding to EBOV GP was obtained using recombinant human adenovirus 5, expressing GP (Ad5-GP) for alpaca (Vicugna pacos) immunization, for the first time. Based on specific activity assay results, affinity constants, and the virus-neutralizing activity against the recombinant vesicular stomatitis virus pseudotyped with EBOV GP (rVSV-GP), the most promising clone (aEv6) was selected. The aEv6 clone was then modified with the human IgG1 Fc fragment to improve its pharmacokinetic and immunologic properties. To assess the protective activity of the chimeric molecule aEv6-Fc, a lethal model of murine rVSV-GP infection was developed by using immunosuppression. The results obtained in lethal model mice have demonstrated the protective effect of aEv6-Fc. Thus, the nanobody and its modified derivative obtained in this study have shown potential protective value against Ebola virus.

Введение БЦЖ (Бацилла-Кальмета-Герена) вакцина - единственная разрешенная к применению, позволяющая противостоять Mycobacterium tuberculosis. Разработка международных требований к производству и контролю БЦЖ вакцины находится под контролем экспертного комитета ВОЗ по биологической стандартизации (Expert Committee on Biological Standardization, ECBS). В 2009 г. ECBS учредил референсы ВОЗ для БЦЖ вакцины на основе трех субштаммов: Danish1331, Tokyo 172-1 и Russian BCG-I, а также требования к контролю, включающие генетическую характеристику произведенных и посевных серий вакцинного субштамма. Согласно требованиям ВОЗ и надлежащей производственной практики (GMP) было выполнено секвенирование трех посевных серий BCG Russia на платформе 454 Roche в нашей лаборатории. БЦЖиты (лимфадениты, остеомиелиты - осложнения при вакцинации БЦЖ) составляют 1% у здоровых реципиентов, однако занимают третье место среди поствакцинальных осложнений в Российской Федерации. Цель наших исследований заключалась в выявлении генетических особенностей субштамма BCG Russia для разработки экспресс-типирования при осложнениях. Методы Полногеномное секвенирование на платформе 454 Roche. MIRU-VNTRplus database для анализа отличий в профилях BCG субштаммов. Набор биоинформационных ресурсов для аннотирования и исследования геномов. Результаты Геном BCG Russia 368 был секвенирован и депонирован в GenBank (Accession Number NZ_CP009243.1). Сравнение геномов последней генерации субштамма и двух предшествующих продемонстрировало стабильность субштамма BCG Russia. Отличие от ближайшего раннего субштамма BCG Tokyo 172 включало 2 RD (region of difference): инсерцию 22 bp и делецию 1602 bp, десять ins/del (1-9 bp) и 52 SNP. Профиль выявленных профагов в геномах M. bovis и M. bovis BCG отражал эволюцию вакцинных субштаммов. Геномы M. bovis содержали профаги 7.5 и 20.3 kb, ранние BCG субштаммы имели профаги 7.5 and 11.2 kb. Большинство поздних субштаммов утратило профаг 11.2 kb. Исключение составили BCG Montreal and BCG Tice, в геномах которых выявлено 6 и 15 профагов, соответственно. Анализ 27 MIRU-VNTR локусов в геноме BCG Russia 368, их сравнение с профилями локусов штаммов M. bovis и BCG субштаммов в MIRU-VNTRplus database позволили обосновать специфичность семи локусов для субштамма BCG Russia. Мы выбрали Mtub21 и Mtub04 - локусы без повторов в геноме BCG Russia, Mtub-30, QUB-26, QUB-323222 -наиболее вариабельные среди M. bovis и M. bovis BCG, и VNTR-3820 и VNTR-4120 как гипервариабельные локусы. Фрагмент анализ этих локусов позволит провести экспресс тестирование при БЦЖитах. Заключение Полногеномное секвенирование - успешный подход в сравнении близкородственных субштаммов и в выявлении специфических локусов для диагностической панели.

The investigation of the bacterial populations’ heterogeneity contributes to the control of natural foci, causative agents of nosocomial infections, to the analysis of the microbial evolution. Multilocus sequence typing (MLST) was employed for the analysis of the diversity and features of the distribution of polyhostal ubiquitous microorganisms of the genera Burkholderia, Leptospira, and Listeria, which belong to three bacterial phyla: Proteobacteria, Spirochaetes, and Firmicutes. According to the bacterial samples analysis microbial genotypes prevalent and unique to Russia were identified; their occurrence in different Federal Regions was investigated; their similarity with global spread genotypes was appreciated. Obtained results allowed identifying common regularities of the selection of the microorganisms capable to cause the diseases of human and animals. The formation of genotypes that are most pathogenic for the host was demonstrated for all groups of bacteria. Leptospira spp. and Listeria monocytogenes strains with these genotypes have been circulating for a long time, being supported by natural foci. The formation of a wide variety of genotypes with different pathogenicity was demonstrated in the local geographic areas. In Russia, the zonal difference in all three groups of bacteria is most clearly traced to the Far Eastern Federal Region. The results are thought to contribute to analyzing the factors of selection and the phylogeny of the taxa under study.

Background and aims. Achromobacter spp., as causative agent of the nosocomial infections, has caught the eye last Decades. The growth of the infecting of the respiratory tract of the cystic fibrosis patients by this microorganism is formidable. The aim of this investigation was the Achromobacter spp. identification in expanded cohort of the Russian CF patients, genotyping of the microorganism according to the international standards and molecular epidemiological analysis of the situation with this opportunistic microorganism. Methods. Clinical samples from about 300 patients: sputum, tracheal aspirate, throat swabs and strains, isolated from the samples, were the material for the investigation. Method of the multilocus sequence typing (MLST), extended by the additional targets, was the base for the research. Results. 25 percents of the patients routinely hospitalized because of the severity of the disease, were infected by Achromobacter spp. of five species: A. xylosoxidans, A. ruhlandii, A. marplatensis, A. dolens, A. pulmonis, and one genogroup. The species A. ruhlandii has dominated (58.5%). One of the drug resistance indicator – oxacillinase gene blaOXA – helps in the differentiation of the genera Achromobacter and Burkholderia, and also some species in the genus Achromobacter. From 26 identified Achromobacter spp. genotypes (sequence type, ST) 16 STs relate to the species A. xylosoxidans, five – to A. ruhlandii. ST263 is specific to the patients from the Far Eastern Federal District. ST261 and 36 are the most numerous: the patients of all Federal Districts are infected by this ST. The chronological analysis allows suggesting the replacement of the genotype 261 by the genotype 36 in the end of the 1990s years and the A. ruhlandii ST36 nosocomial outbreak. At present 39% of the patients with Achromobacter spp. are infected by A. ruhlandii ST36, transmissivity of which is proved the coinfection cases of the siblings and simultaneously hospitalized patients. The influence on the respiratory function of the CF patients was the most expressed for the A. ruhlandii ST261strains. For the younger age group (1997 year of birth and younger), infected by A. ruhlandii ST36, the median of the FEV1 was slightly lower than in older age group, infected by those strain, that can indicate the accumulation of the pathogenic properties by the A. ruhlandii ST36 during the circulation between the patients. Conclusions. A. ruhlandii ST36 strain by the combination of the identified properties may be considered as the Russian epidemic strain.