SUMMARYMultiple sclerosis (MS) is assumed to result from autoaggressive T cell-mediated immune responses, in which T helper type 1 (Th1) cells producing cytokines, e.g. IFN-g and lymphotoxin promote damage of oligodendrocyte-myelin units. Dendritic cells (DCs) as potent antigen presenting cells initiate and orchestrate immune responses. Whether phenotype and function of DCs with respect to Th1 cell promotion are altered in MS, are not known. This study revealed that blood-derived DCs from MS patients expressed low levels of the costimulatory molecule CD86. In addition, production of IFN-g by blood mononuclear cells (MNCs) was strongly enhanced by DCs derived from MS patients. IFNb and IL-10 inhibited the costimulatory capacity of DCs in mixed lymphocyte reaction (MLR) and showed additive effects on suppression of IL-12 production by DCs. Correspondingly, DCs pretreated with IFN-b and IL-10 significantly suppressed IFN-g production by MNCs. IFN-b in vitro also upregulated CD80 and, in particular, CD86 expression on DCs. In vitro, anti-CD80 antibody remarkably increased, while anti-CD86 antibody inhibited DC-induced IL-4 production in MLR. We conclude that DC phenotype and function are altered in MS, implying Th1-biased responses with enhanced capacity to induce Th1 cytokine production. In vitro modification of MS patients' DCs by IFN-b and IL-10 could represent a novel way of immunomodulation and of possible usefulness for future immunotherapy of MS.

This article describes a lethal case of leptospirosis that occurred in Southern Russia. The Leptospira strain was isolated and characterized using a microscopic agglutination test, MALDI-TOF mass spectrometry, targeted PCR, and high-throughput sequencing. We show that molecular and mass-spectrometry methods can be an alternative to conventional methods of leptospirosis diagnostics and Leptospira study, which require highly qualified staff and can be performed only at specialized laboratories. We also report the first whole genome of L. interrogans isolated in Russia.

Objective: The uptrend in the incidence of Tick-borne Diseases (TBD) is a new challenge for public health in many countries, especially those in the Arctic zone. The objective of our study was to assess the TBD seroprevalence in the population of Komi Republic (KR) located in the northeast of European Russia. Materials and methods:Blood serum was sampled from 343 (183 men, 160 women) healthy donors aged 20-70 and tested with Enzyme-Linked Immunosorbent Assay (ELISA).Results: IgG antibodies to TBD pathogens were detected in 66 (19.2%) samples: 47 (13.7%) samples contained antibodies to TBE virus, 18 (5.3%) those to Borrelia, and 5 (1.5%) those to Anaplasma phagocytophilum, 4 samples contained antibodies to TBE mixed with those to another TBD. The results were compared with those of an earlier serological survey and showed a significant increase in the seroprevalence IgG antibodies to TBE (13.7 ± 1.9% in 2013, and 3.5 ± 0.75% in 2001, respectively). In the sera samples of occupationally-risk professionals the IgG antibodies to TBD were more common than in the rest of donors (36.2 ± 7.0% and 16.6 ± 2.2%; p<0.05), in men more common than in women (25.1 ± 3.2% and 12.5 ± 2.6%; p<0.01), and young men (20-34 years) were the most affected. Discussion:The situation in KR justifies the need for professional advancement of medical practitioners in TBD treatment, and revision of regional plans for anti-epidemic measures. Attention should be given to the effectiveness of health education, particularly among indigenous people who inhabit territory where tick bites are recorded. Conclusion:Significant growth of TBE seroprevalence evidences the increased risk of acquiring TBE by KR population, including the inhabitants of settlements where this infection was never reported previously.

Aim. An attempt to use MALDI-TOF mass-spectrometry method for identification of leptospiral isolates on the serovar level. Materials and methods. 8 reference Leptospira spp. and 11 leptospira strains isolated from leptospiral patients and infected animals in the North-VNfestem region of Russia were included into the study. Mass-spectra of all the studied strains were obtained by direct profiling of cell extracts. The created main spectral profiles (MSP) of reference strains were used for identification of isolates. Evaluation of identification was carried out by calculating coefficients of matching rate of separate spectra of each isolate with MSP of all the reference strains. Results. Results of identification have shown the similarity of spectra of isolates belonging to Pomona, Icterohaemorrhagiae and Canicola serogroups, with MSP of saprophyte strain L. biflexa Patoc I. It is assumed that spectra of the studied strains contained peaks of polysaccharide O-antigens. Wherein maximum mean values of matching rate coefficients between spectra of isolates and MSP of pathogenic reference strains of leptospira correctly matched serovar type of the isolate. Conclusion. Further extended studies may form the base of development of a simple and rapid method of typing of leptospirosis causative agents on the level of serovars using MALDI-TOF mass-spectrometry.

Introduction. Knowledge about tick-borne disease (TBD) distribution is necessary to improve prevention, whereas detection of human serum IgG antibodies against relevant pathogens is a method for monitoring TBD prevalence in local population. The study objective was to estimate seroprevalence of IgG antibodies against tick-borne encephalitis virus (TBEV), Borrelia burgdorferi sensu lato, Coxiella burnetii, Anaplasma phagocytophilum, and Ehrlichia chaffeensis/E. muris in healthy residents from the five territories of the Northwestern Federal District of the Russian Federation (Arkhangelsk Oblast, Leningrad Oblast, Pskov Oblast, the Republic of Komi and the Republic of Karelia). Materials and methods. In 20172019, a total of 1244 serum samples from healthy residents, not vaccinated against TBDs or other flavivirus-caused infections was studied by ELISA. Results. 21.7% of the sera samples contained IgG antibodies against a single TBD pathogen, whereas 2.1% showed signs of coinfection with two or more pathogens. The most common were IgG antibodies against TBEV (5 territories, 12.2%), followed by Borrelia burgdorferi sensu lato (5 territories, 3.5%), C. burnetii (4 territories, 2.9%), Anaplasma phagoсytophilum (3 territories, 1.6%), E. chaffeensis/E. muris (5 territories, 1.5%). The IgG antibodies were more common in men (55.2%) than in women (44.8%), being found virtually evenly in age-independent manner (from juniors under 18 to seniors over 60). Conclusion. The results of this first comprehensive serosurveillance study in the Northwestern Federal District of the Russian Federation assessing serum IgG antibodies against tick-borne diseases indicate a wide distribution of such pathogens. Moreover, infections caused by C. burnetii, Anaplasma phagocytophilum, and Ehrlichia chaffeensis/E. muris might be highly underdiagnosed.

Aim. Comparative typing of Leptospira spp. strain collection based on analysis of 16S RNA fragment. Materials and methods. 2 pairs of primers were used for PCR, that jointly flank 1423 b.p. sized fragment. Sequences of Leptospira spp. strain 16S rRNA, presented in the international database, were used for phylogenetic analysis. Results. A high similarity, including interspecies, of the 16S fragment in Leptospira spp. strains was shown independently of the source, serovar and serogroup. Heterogeneity ofthe primary matrix, spontaneous mutations of hotspots and erroneous nucleotide couplings, characteristic for 16S sequence of pathogenic Leptospira spp. strains, are discussed. Molecular-genetic characteristic of certain reference Leptospira spp. strains by 16S sequence is obtained. Conclusion. Results of the studies give evidence on expedience of introduction into clinical practice of identification of Leptospira spp. by 16S sequence directly from the clinical material, that would allow to significantly reduce identification time, dismiss complex type-specific sera and other labor-intensive methods.

Species-specific recombinant proteins of leptospira are genetically engineered by the method of gene manipulation. Their high activity and antigenic specificity are established. On the basis of these proteins an immunoassay test kit for detecting JgG to Leptospira is constructed. Key words: leptospirosis, diagnostics ВведениеЛептоспироз является широко распространен-ной и социально значимой зооантропонозной ин-фекцией. Полиморфизм клинических проявлений лептоспироза и отсутствие патогномоничных сим-птомов болезни приводят к поздней диагностике, нерациональному лечению, что становится одной из причин высокой летальности при этой инфекции [1 -3]. Относительно низкие показатели регистри-руемой заболеваемости людей, несопоставимые с множественностью потенциальных источников ин-фекции, в большинстве стран мира, включая Рос-сию, обусловлены неудовлетворительным состоя-нием лабораторной диагностики [4].В значительной степени трудности серологиче-ской диагностики лептоспироза вызваны тем, что, как правило, она осуществляется с помощью реак-ции микроагглютинации (РМА), признанной Между-народным обществом лептоспирологов основным тестом для диагностики этой инфекции [5]. Для по-становки РМА необходимо поддерживать в лабора-торных условиях стандартный набор живых культур лептоспир. Культивирование лептоспир осущест-вляется лишь в специализированных лаборатори-ях, поскольку это связано с большими трудностями. Кроме того, стандартизация учета результатов РМА весьма затруднительна, так как они оценивают-ся визуально с помощью микроскопа. Сказанное аргументирует разработку лептоспирозных диа-гностических систем со стандартными способами оценки результатов анализа, применение которых будет возможно практически в любой серологиче-ской лаборатории. Одним из перспективных под-ходов к решению этой задачи является получение на основе современных методов генной инжене-рии родоспецифичных рекомбинантных антиге-нов лептоспир для конструирования на их основе диагностических тест-систем. Анализ литературных данных показал, что наиболее перспективными в данном отношении могут быть гены lipL32, lipL41 и lipL45 [6, 7].Цель данной работы -получение родоспе-цифических белков лептоспир, пригодных для кон-струирования иммуноферментной тест-системы для диагностики лептоспироза. Материалы и методыВ работе были использованы патогенные леп-тоспиры серогрупп Icterohaemorrhagiae, Canicola, Grippotyphosa из коллекции НИИ эпидемиологии и микробиологии им. Пастера.ДНК из лептоспир были выделены стандартным методом c использованием протеиназы К и фенол-хлороформной экстракции [8]. Гены lipL32, lipL41,

.