Humanized Mouse Model of HIV Infection.

The development of new drugs for the treatment of HIV infection requires testing of their efficacy in a relevant animal model, such as humanized mice, which, unfortunately, are not yet available in Russia. In the present study, we have developed conditions for the humanization of immunodeficient NSG mice with human hematopoietic stem cells. Humanized animals generated during the study showed a high degree of chimerism and harbored repopulation of the entire range of human lymphocytes required for HIV replication in the blood and organs. Inoculation of these mice with HIV-1 virus led to stable viremia, which was confirmed by the presence of viral RNA in blood plasma throughout the entire period of observation and proviral DNA in the organs of animals 4 weeks after HIV infection.

[HIV Restriction Factor APOBEC3G and Prospects for Its Use in Gene Therapy for HIV].

The mechanisms for the protection of the human body from viral or bacterial agents are extremely diverse. In one such mechanism, an important role belongs to the cytidine deaminase APOBEC3 family, which is the factor of congenital immunity and protects the organism from numerous viral agents. One of the proteins of this family, APOBEC3G, is able to protect against Human Immunodeficiency Virus type 1 in the absence of viral protein Vif. In turn, Vif opposes APOBEC3G action, causing polyubiquity of the protein and degradation in the proteasome. The review describes possible ways to increase the anti-HIV activity of APOBEC3G, giving it resistance to viral protein Vif, as well as potential approaches to the use of modified APOBEC3G in gene therapy for HIV.

[The Titer of the Lentiviral Vector Encoding Chimeric TRIM5α-HRH Gene is Reduced Due to Expression of TRIM5α-HRH in Producer Cells and the Negative Effect of Efla Promoter].

The chimeric protein TRIM5α-HRH is a promising antiviral factor for HIV-1 gene therapy. This protein is able to protect cells from HIV-1 by blocking the virus in the cytoplasm. We are developing protocol of HIV-1 gene therapy, which involves the delivery of the TRIM5α-HRH gene into CD4^(+) T-lymphocytes by lentiviral vectors (LVs). However, LVs containing TRIM5α-HRH have a low infectious titer, which prevents effective T cell modification. Here, we found that the expression of TRIM5α-HRH during pseudoviral particle production in HEK293 T cells, as well as the presence of the Eflα promoter in our construction are responsible for titer reduction. These results allow us to determine the directions for further optimization of LV with the TRIM5α-HRH gene to improve its infectious titer.

[Generation of SARS-CoV-2 Mouse Model by Transient Expression of the Human ACE2 Gene Mediated by Intranasal Administration of AAV-hACE2].

One of the most important steps in the development of drugs and vaccines against a new coronavirus infection is their testing on a relevant animal model. The laboratory mouse, with well-studied immunology, is the preferred mammalian model in experimental medicine. However, mice are not susceptible to infection with SARS-CoV-2 due to the lack of human angiotensin-converting enzyme (hACE2), which is the cell receptor of SARS-CoV-2 and necessary for the entry of the virus into the cell. In present work, it was shown that intranasal administration of the adeno-associated vectors AAV9 and AAV-DJ encoding the hACE2 provided a high level of expression of ACE2 gene in the lungs of mice. In contrast, the introduction of the AAV6 vector led to a low level ACE2 expression. Infection with SARS-CoV-2 of mice expressing hACE2 in the lungs led to virus replication and development of bronchopneumonia on the 7th day after infection. Thus, a simple method for delivering the human ACE2 gene to mouse lungs by intranasal administration of the AAV vector has been proposed. This approach enabled rapid generation of mouse model for studying coronavirus infection.

Serological diagnosis and prevalence of HIV-1 infection in Russian metropolitan areas.

BACKGROUND: HIV infection is a major health problem in Russia. We aimed to assess HIV prevalence in different population groups and to compare the characteristics of 4th generation immunoassays from Abbott, Bio-Rad, Vector-Best, Diagnostic Systems, and Medical Biological Unit. METHODS: The study included 4452 individuals from the general population (GP), 391 subjects at high risk of HIV infection (HR) and 699 with potentially interfering conditions. HIV positivity was confirmed by immunoblot and by HIV RNA, seroconversion and virus diversity panels were also used. HIV avidity was employed to assess recent infections. RESULTS: The prevalence in GP was 0.40%, higher in males (0.62%) and in people aged < 40 years (0.58%). Patients attending dermo-venereal centers and drug users had a high prevalence (34.1 and 58.8%). Recent infections were diagnosed in 20% of GP and in 4.2% of HR. Assay sensitivity was 100% except for one false negative (99,54%, MBU). Specificity was 99.58-99.89% overall, but as low as 93.26% on HR (Vector-Best). Small differences on early seroconversion were recorded. Only the Abbott assay detected all samples on the viral diversity panel. CONCLUSION: HIV infection rate in the high-risk groups suggests that awareness and screening campaigns should be enhanced. Fourth generation assays are adequate but performance differences must be considered.

[Retrovirus Restriction Factor TRIM5α: The Mechanism of Action and Prospects for Use in Gene Therapy of HIV Infection].

It is commonly known that the antiviral activity of the TRIM5α protein, the intracellular retrovirus restriction factor, underlies the resistance of the Old World monkeys to HIV-1. This fact suggests that TRIM5α can potentially be used to cure HIV-1 infection in humans. The present review considers the mechanisms of HIV-1 replication inhibition by the TRIM5a protein and the prospects for using it in gene therapy of HIV infection.

[Protection of Lymphocytes Against HIV using Lentivirus Vector Carrying a Combination of TRIM5α-HRH Genes and microRNA Against CCR5].

Gene therapy is considered a promising approach to treating infections caused by human immunodeficiency virus (HIV). One strategy is to introduce antiviral genes into cells in order to impart resistance to HIV. In this work, the antiviral activity of new anti-HIV lentiviral vector pT has been studied. The vector carries a combination that consists of two identical artificial miRNA mic13lg and the TRIM5α-HRH gene. Two mic13lg microRNAs suppress the expression of the CCR5 gene, which encodes the HIV coreceptor and, thus, prevents the penetration of R5-tropic HIV strains into the cell. It has been shown that pT effectively inhibits the expression of CCR5 in both the HT1080 CCR5-EGFP model cell line and in human primary lymphocytes. The second line of protection against R5- and X4-tropic HIV is provided by the TRIM5α-HRH protein, which binds virus capsids after the virus enters the cell. Indeed, when infecting cells of the SupT1 line, which contains four copies of the vector per cell, with the X-4 tropic HIV, more than 1000-fold suppression of viral replication has been observed. The process of generation of the pT vector and conditions of transduction of CD4^(+) lymphocytes were optimized for testing the antiviral activity of the vector on primary human lymphocytes. As a result, the transduction efficiency for the pT vector was 28%. After infection with the R5-tropic strain of the virus, the survival of cells in the culture of lymphocytes with the vector was significantly higher than in the control. However, the complete suppression of HIV replication was not achieved, presumably due to the inadequate fraction of cells that carry the vector in culture. In the future, it is planned to find the best way to enrich the lymphocyte culture with modified cells to increase resistance to HIV.

[Allele-specific polymerase chain reaction and electrophoretic detection in the detection algorithm clinically significant somatic mutations in the gene of calreticulin (calr).]

The detection of somatic mutations in the 9 exon of the calreticulin gene (CALR) is regulated by the clinical recommendations as a diagnostic criterion for chronic Ph-negative myeloproliferative neoplasms (MPN). Some methods of nucleic acids testing are used to identify CALR gene mutations with different requirements for special skills of personnel and expensive equipment. The purpose of this work is to compare the results of the detection of CALR gene mutations in venous blood samples by allele-specific RT-PCR with subsequent electrophoresis, fragment analysis and Sanger- or pyro- sequencing. We used 1284 blood samples of patients with suspected MPN and 20 blood donor samples. Mutations in the CALR gene of the I and II type were identified using PCR-RT with the original primers and TaqMan probes. Also, all samples were tested for mutations in the CALR gene by electrophoretic detection of PCR results in an agarose gel. The use of allele-specific RT-PCR followed by electrophoretic detection made it possible to determine clinically significant mutations in the CALR gene in 81 venous blood samples of JAK2- and MPL-negative patients, including 42 cases of type I mutation, 33 cases of type II mutation and 8 rare CALR mutations. Mutations in the 9 exon of the CALR gene were not detected in any of the 20 blood donor samples or in 121 blood samples of patients with polycythemia vera. In randomly selected 20 negative samples, CALR gene mutations were also not detected using Sanger sequencing. All positive samples were confirmed by fragment analysis, as well as with Sanger- sequencing and pyro- sequencing. The described combined approach to detect mutations of the CALR gene in peripheral blood samples can be used in clinical diagnostic laboratories that have a standard set of equipment for electrophoresis of nucleic acids and a PCR-RT. We also propose a confirmatory test based on the pyrosequencing of DNA using the system of genetic analysis "PyroMark Q24".

[The development and approbation of methodology on the basis of multiplex polymerase chain reaction in real-time to determine clinically significant micro-deletion in Y-chromosome.]

One of the prevalent genetic causes of idiopathic male sterility is related to micro-deletions in AZF locus located in Y-chromosome. In total population, rate of such micro-deletions makes up to 1:4000. however, in infertile males their rate varies from 2% to 10%. In AZF locus three subregions are distinguished: AZFa, AZFb and AZFc. The loss of one or several subregions can result in disorder of spermatogenesis of various degree - from decreasing of its activity to Sertoli-cell syndrome manifested by azoospermia or oligospermia of severe degree. Therefore, implementation of genetic testing for presence of micro-deletions in AZF locus is a necessary test in case of prognosis of male sterility and its treatment. The purpose of study is to develop and test a diagnostic system of detection of micro-deletions in subregions of AZF locus using multiplex polymerase chain reaction in real-time. As a reference method a technique was implemented described in guidelines of the European Academy of Andrology conjointly with European Molecular Genetics Quality Network. The technique testing specified analysis of 33 samples of DNA separated from blood of males with azoospermia and oligospermia of severe degree. No discordant results were received as compared with reference method. In 27 DNA samples the deletions were detected in AZF locus: 4 AZFa deletions (15%), 2 AZFb deletions (7%), 17 AZFc deletions (63%) and 6 combined deletions of AZFb+candи AZFa+b+с (22%). The proposed technique permits detect micro-deletions of subregions of AZF locus.

[Overexpression of DNA-methyltransferases in persistency of cccDNA pool in chronic hepatitis B]. / Rol' giperékspressii DNK-metiltransferaz v persistentsii kol'tsevoi kovalentno zamknutoi DNK pri khronicheskom gepatite V.

AIM: To define the role of DNA-methyltransferases of type 1 and type 3A in hepatitis B viral cycle. MATERIAL AND METHODS: Human hepatoma cells HepG2 with stable expression of 1.1-mer HBV genome were transfected with vectors encoding DNA-methyltransferase 1 (DNMT1), DNA-methyltransferase 3A (DNMT3A) or were co-transfected with these vectors. Total HBV DNA copy number, relative expression of pregenomic RNA (pgRNA), S-protein-encoding RNA (S-RNA) and cccDNA were analyzed by quantitative and semi-quantitative real-time PCR-analysis with TaqMan probes for assessment of DNMTs-mediated effects on HBV. RESULTS: DNMT1 and DNMT3A suppress HBV transcription and replication, though to different magnitude. cccDNA pool is enlarged statistically significantly ≈2-fold (P<0.005) after transfection of DNMT3A, but is unaltered under DNMT1 treatment. CONCLUSION: DNMT3A regulates the size of cccDNA pool and is important for persistency of HBV infection.

[Clinical presentation of Ixodes tick-borne borreliosis caused by Borrelia miyamotoi in the context of an immune response to the pathogen]. / Klinicheskie proiavleniia iksodovogo kleshchevogo borrelioza, vyzvannogo Borrelia miyamotoi, v kontekste immunnogo otveta na vozbuditel'.

Ixodes tick-borne borreliosis caused by Borrelia miyamotoi (ITBB-BM) is a previously unknown infectious disease discovered in Russia. AIM: The present study continues the investigation of the clinical features of ITBB-BM in the context of an immune system-pathogen interaction. SUBJECTS AND METHODS: The study enrolled 117 patients with ITBB-BM and a comparison group of 71 patients with Lyme disease (LD) that is ITBB with erythema migrans. All the patients were treated at the New Hospital, Yekateringburg. More than 100 clinical, epidemiological and laboratory parameters were obtained from each patient's medical history and included in the general database. A subset of patients hospitalized in 2015 and 2016 underwent additional laboratory examinations. Namely, the levels of B. miyamotoi-specific IgM and IgG antibodies were measured by the protein microarray containing GlpQ protein and four variable major proteins (VMPs): Vlp15/16, Vlp18, Vsp1, and Vlp5. The blood concentration of Borrelia was estimated by quantitative real-time PCR. RESULTS: In contrast to LD, first of all (p<0.001) the following clinical features were typical for ITBB-BM: the absence of erythema migrans (in 95% of patients), fever (93%), fatigue (96%), headache (82%), chill (41%), nausea (28%), lymphopenia (56%), thrombocytopenia (46%), the abnormal levels of alanine aminotransferase (54%) and C-reactive protein (98%), proteinuria (61%). Given the set of these indicators, the course of ITBB-BM was more severe in approximately 70% of patients. At admission, only 13% and 38% of patients had antibodies to GlpQ and VMPs, respectively; at discharge, antibodies to GlpQ and VMPs were detected in 88% of patients. There was no statistically significant association of the antibody response with individual clinical manifestations and laboratory parameters of the disease. However, patients with more severe ITBB-BM produced less IgM antibodies to VMPs and GlpQ at the time of discharge. CONCLUSION: ITBB-BM is a moderate systemic disease accompanied by the production of specific antibodies in virtually all patients.

[Molecular epidemiological analysis of HIV-1 variants circulating in Russia in 1987-2015]. / Molekuliarno-épidemiologicheskii analiz variantov VICh-1, tsirkulirovavshikh v Rossii v 1987-2015 gg.

AIM: To simultaneously analyze HIV-1 samples from all Russian regions to characterize the epidemiology of HIV infection in the country as a whole. SUBJECTS AND METHODS: The most extensive study was conducted to examine nucleotide sequences of the pol gene of HIV-1 samples isolated from HIV-positive persons in different regions of Russia, with the diagnosis date being fixed during 1987-2015. The nucleotide sequences of the HIV-1 genome were analyzed using computer programs and on-line applications to identify a virus subtype and new recombinant forms. RESULTS: The nucleotide sequences of the pol gene were analyzed in 1697 HIV-1 samples and the findings were that the genetic variant subtype A1 (IDU-A) was dominant throughout the entire territory of Russia (in more than 80% of all infection cases). Other virus variants circulating in Russia were analyzed; the phenomenon of the higher distribution of the recombinant form CRF63/02A in Siberia, which had been previously described in the literature, was also confirmed. Four new recombinant forms generated by the virus subtype A1 (IDU-A) and B and two AG recombinant forms were found. There was a larger genetic distance between the viruses of IDU-A variant circulating among the injecting drug users and those infected through heterosexual contact, as well as a change in the viruses of subtype G that caused the outbreak in the south of the country over time in 1988-1989. CONCLUSION: The findings demonstrate continuous HIV-1 genetic variability and recombination over time in Russia, as well as increased genetic diversity with higher HIV infection rates in the population.

[The development and comparative approbation of methods of increasing sensitivity of detection of mutation V617F in gene JAK2 by pyro-sequencing].

The possibilities of early detection of chronic myelo-proliferative tumors (MPT) are determined by sensitivity of techniques implemented for finding somatic mutation V617F in gene JAK2. The mutation V617F can also be found in individuals without unfolded picture of hematological diseases. The detection of mutation even in low concentrations is associated with increasing of risk of cerebral stroke and thrombosis of arterial and venous vessels. The study was carried out to develop techniques based on COLD polymerase chain reaction and allele-specific polymerase chain reaction targeted to increasing of sensitivity of finding mutation V617F detected using pyro-sequencing. The analytical sensitivity of techniques was evaluated by control samples with different ratio of alleles. For allele-specific polymerase chain reaction analytical sensitivity amounted to 0.25% of mutant allele at concentration of analyzed control sample 10 copies of DNA per mkl. For COLD polymerase chain reaction sensitivity amounted to 0.5% at concentration 10 copies of DNA per mkl. The comparative approbation of techniques was implemented using clinical material obtained from 106 patients with suspicion on MPT. The analysis of clinical samples using COLD polymerase chain reaction revealed 13 (14%) and using technique of allele-specific polymerase chain reaction - 15 (16%) positive samples. In all 15 cases of detection of mutation clinical confirmations of diagnosis of MPT was received. The proposed techniques permit increasing efficiency of amplification of mutant DNA in analyzed samples and hence to increase sensitivity of subsequent analysis of products of amplification using technique of pyro-sequencing. Therefore, the mentioned techniques can be recommended to be applied for confirmation of diagnosis of MPT and early identification of individuals with increased risk of development of venous and arterial thromboses.

Development and evaluation of the RT-PCR kit for the rabies virus diagnosis.

To improve the diagnosis, surveillance, and control for the rabies virus, a kit for hybridization-triggered fluorescence detection of rabies virus DNA by the RT-PCR technique was developed and evaluated. The analytical sensitivity of the kit was 4*10 GE per ml. High specificity of the kit was shown using representative sampling of viral, bacterial, and human nucleic acids.

[CONTEMPORARY MOLECULAR-GENETIC METHODS USED FOR ETIOLOGIC DIAGNOSTICS OF SEPSIS].

Etiologic diagnostics of sepsis is one of the most difficult problems of contemporary medicine due to a wide variety of sepsis causative agents, many of which are components of normal human microflora. Disadvantages of contemporary "golden standard" of microbiologic diagnostics of sepsis etiology by seeding of blood for sterility are duration of cultivation, limitation in detection of non-cultivable forms of microorganisms, significant effect of preliminary empiric antibiotics therapy on results of the analysis. Methods of molecular diagnostics that are being actively developed and integrated during the last decade are deprived of these disadvantages. Main contemporary methods of molecular-biological diagnostics are examined in the review, actualdata on their diagnostic characteristic are provided. Special attention is given to methods of PCR-diagnostics, including novel Russian developments. Methods of nucleic acid hybridization and proteomic analysis are examined in comparative aspect. Evaluation of application and perspectives of development of methods of molecular diagnostics of sepsis is given.

[Follow-up of patients with Ixodes tick-borne borrelioses caused by Borrelia miyamotoi or Borrelia burgdorferi sensu lato]. / Katamnez bol'nykh iksodovymi kleshchevymi borreliozami, vyzvannymi Borrelia miyamotoi ili Borrelia burgdorferi sensu lato.

Ixodes tick-borne borrelioses (ITBB) are caused by two different spirochetes: Borrelia from the group of Borrelia burgdorferi sensu lato, the agents of the classic Lyme borreliosis (LB), and Borrelia miyamotoi that belongs to the group of Borrelia causing tick-borne relapsing fevers. ITBB caused by B. miyamotoi (BM-ITBB) is a previously unknown infectious disease discovered in Russia. It is known that the LB sequelae may reduce the long-term life guality of convalescents. AIM: To study the follow-up of those who have recovered from new BM-ITBB infection in comparison with persons who have had LB. SUBJECTS AND METHODS: The investigation enrolled 41 patients with BM-ITBB and 41 patients with LB who were treated at the Republican Infectious Diseases Hospital of Udmurtia. Within a year after the disease, they were followed up through clinical and instrumental examination of cardiac performance, expanded biochemical analysis of blood and urine, which could; estimate kidney and liver functions, and psychological questioning. RESULTS: Asthenic syndrome and complaints about and objective signs of cardiac dysfunctions persisted supraventricular extrasystoles, left ventricular diastolic dysfunction, and elevated and/or unstable systolic blood pressure were detected in 20-30% of the convalescents for a long time. Kidney dysfunctions were manifested in albuminuria and the decrease of glomerular filtration rate. A year following the disease, 10-20% patients had persistently elevated concentrations of alanine aminotransferase, aspartate aminotransferase, and C-reactive protein and had higher levels of total cholesterol and low-density lipoproteins. The pathological consequences of ITBB were polymorphic and varied in different patients; in general, only 68% of them showed health improvement. CONCLUSION: We assume that a significant role in the pathogenesis of BM-ITBB and LB is played by vascular endothelial damage possibly associated with the inflammatory and autoimmune aspects of an immune response in Borrelia infection. The consequences of this damage may persist and even intensify during a year, which provokes chronic dysfunction of the heart, kidney, or liver in a number of convalescents.

[Infective endocarditis: Importance of molecular biological techniques in etiological diagnosis]. / Infektsionnyi endokardit: znachenie molekulyarno-biologicheskikh metodov v etiologicheskoi diagnostike.

AIM: To investigate the specific features of conventional bacteriological methods and current molecular biological techniques for the etiological diagnosis of infective endocarditis (IE). SUBJECTS AND METHODS: Examinations were made in 53 patients treated at City Clinical Hospital Sixty-Four, Moscow Healthcare Department, in 2012-2015 who underwent simultaneous bacteriological and molecular biological (polymerase chain reaction (PCR) or PCR with further sequencing) examinations of blood or resected cardiac valve tissues. RESULTS: The investigation included 53 patients (31 men; median age, 62 years) with IE (Duke 2009); its primary form was observed in 32 (60.4%) patients. Blood bacteriological tests and PCR assays were positive in 28 (52.8%) and 34 (64.2%) patients, respectively. There were concordant results in 21 of the 28 positive blood culture cases and discordant results in 7 (25%); at the same time 3 cases showed a compete discordance in the detected causative agents (the growth of Enterococcus spp. was revealed by bacteriological examination and that of Staphylococcus spp., Streptococcus spp., and Escherichia coli by DNA PCR) and a pathogen could not be identified by DNA PCR in 4 patients who had positive blood bacteriological results. The positive PCR results for cocci and fungi were obtained in 10 of the 25 (47.2%) examinees with culture-negative IE. Rare causative agents were not revealed. The tissues obtained from 8 resected damaged heart valves displayed a wider spectrum of pathogens than did blood samples, which was associated with the formation of bacterial films. CONCLUSION: The etiological agent of IE was revealed in venous blood by bacteriological examination in 52.8% of the examinees, by PCR in 64.2%, and by either in 71.7%. There were concordant and discordant results in 67.9 and 32.1% of the patients, respectively; among whom 18.9% were found to have pathogen DNA revealed by PCR in culture-negative IE.

[The comparison of three molecular genetic techniques for identifying major mutations in gene HFE related to development of inherent hemochromatosis.]

The three main mutations in gene HFE (C282Y, H63D, S65C) are the cause of development of 97% of cases of inherent hemochromatosis. It is known that about 85% of patients with inherent hemochromatosis are either homo-zygotic agents of mutation C282Y or carry compound-heterozygote C282Y/H63D. Therefore, the molecular genetic study intended for detection of these three mutations in gene HFE takes important place in diagnostic of inherent hemochromatosis. The study was organized to develop methods for detection of mutations C282Y, H63D, S65C on the basis of two molecular genetic methods - polymerase chain reaction in real-time and pyrosequenation. As reference method was used published method by Moyses C.B. et al. (2008). These methods were applied to analyzing 129 DNA samples. There were no discordant results. Among analyzed clinical DNA samples, mutant alleles of gene HFE were detected in 42 samples (32.5%)ю The mutation C282Y is detected in heterozygotic condition in 4 samples (3.1%); mutation H63D was detected in heterozygotic condition in 31 samples (24%) and in homo-zygotic condition in 4 samples (4%). The mutation S65C encountered in heterozygotic condition in one sample (0.8%) and in one sample compound-heterozygote H63D/S65C was detected (0.8%). The comparative characteristic of these three methods was made according the following parameters: time, number of analysis stages and convenience of interpretation of results. The main merit of method based on polymerase chain reaction in real-time is time of analysis implementation. The main merit of method based on pyrosequenation is automatic identification of genotype.

[The results of monitoring of antigen types of rotaviruses of group A on the territory of the Russian Federation in 2011-2015.]

The data of seasonal monitoring are presented concerning antigen types of rotaviruses group A circulating on the territory of the Russian Federation in the periods of seasonal uprising of morbidity in 2011-2015. Annually, the study included from 10 to 12 subjects of the Russian Federation with annual testing from 444 to 728 samples from children aged younger than 5 years with acute infection diarrhea. In the seasons of 2011-2012, 2012-2013, 2013-2014, 2014-2015 the most prevalent [P] G types of rotaviruses correspondingly made up to: G4[P]8 -50.2%-36.5%-43.8%-1.6%; G1[P]8 - 26.6%-14.3%-27.3%-22.5%; G3[P]8 - 4.4%-23.7%-4.2%-2.0%; G9[P]8 - 4.3%-5.3%-10.1%-7.1%; G2[P]4 - 7.7%-7.9%-9.0%-3.1%. The expressed territorial irregularity of prevalence of antigen types of retroviruses was observed.

[The blood coagulation system and microcirculatory disorders in ixodid tick-borne borreliosis caused by Borrelia miyamotoi].

AIM: To study blood coagulation and microcirculatory disorders as a possible cause of transient dysfunctions of organs (the kidney, liver, heart, lung, etc.) in patients with ixodid tick-borne borreliosis caused by Borrelia miyamotoi (Bmt). SUBJECTS AND METHODS; Twenty-four patients with Lyme disease (LD) and 28 Bmt patients treated at Izhevsk City Hospital (Udmurtia) were examined in the study. Platelet counts and the presence of D-dimers were determined; activated partial thromboplastin time, prothrombin time, thrombin time, fibrinogen and antithrombin III levels, and Factor XIIa-dependent fibrin clot lysis time were measured. Slit lamp microscopy of the conjunctiva was. also carried out. Results. Platelet counts'were less than 150,000 per pL of blood in 43% of the Bmt patients. All the Bmt patients had at least one abnormal coagulation parameter of the eight ones that were tested; 64% of them had marked coagulation disorders with three or more abnormal laboratory findings. In contrast, all the eight parameters were normal in 71% of the LD patients. The other seven LD patients had only one or two abnormal coagulation parameters (p < 0.001 in comparison with Bmt patients). Microscopic examination of eye capillary blood flow revealed pathological findings that included aggregates of erythrocytes and obstructed and/or sinuous capillaries in 22 (79%) of the Bmt patients, but none of the LD patients. A total of 14 Bmt patients had both coagulation and microcirculatory abnormalities. Eleven of them also had transient signs of organ dysfunction. CONCLUSION: As far as Borrelia secrete no known toxins, we hypothesized that uncovered disorders of blood coagulation and microcirculation in Bmt patients may contribute to organ dysfunction.