[Protease and reverse transcriptase genetic polymorphism in HIV type 1 subtype A variants predominating in cis countries].

To define frequencies of drug resistance mutations among HIV-1 variants circulating within the territory of Russia, subtype A HIV-1 nucleotide sequences encoding protease and reverse transcriptase were analyzed. The analysis was carried out in 141 antiretroviral-naive individuals. Low frequency (less than 1%) of primary drug resistance mutations was shown. However, high frequencies of secondary mutations V77I in protease and A62V in RT (67% H 63%, respectively) linked to each other in most cases were observed. The HIV-1 isolates bearing both substitutions (MutV77I/A62V) were also characterized by the presence of several synonymous mutations, suggesting common origin for these viruses. HIV Biochip Hybridization microarray and/or Restriction fragment-length polymorphism analyses were performed to characterize gene pol polymorphism in additional 178 subtype A HIV-1 isolates. Among total 319 samples studied, Mutv77IA62V variant accounted for 56%, and was found to predominate in Russia in terms of both its geographical distribution and number of cases caused. Moreover, these viruses were prevalent in the regions known to have highest incidence of HIV-1 infection (Irkutsk, Samara, and Moscow regions). In addition, three other variants were found: viruses not containing the substitutions V77I or A62V, and variants bearing only one of them. Evolutional relationships between all four HIV-1 variants, as well as potential impact of the gene pol polymorphism on HIV-1 replicative fitness and drug resistance development are discussed.

[Development of microchips for the detection of mutations of HIV-1 variability to protease inhibitors and the usage results]. / Razrabotka biologicheskikh mikrochipov dlia vyiavleniia mutatsii ustoichivosti VICH-1 k ingibitoram proteazy i rezul'taty ikh primeneniia.

An original biochip was constructed for the detection of 34 mutations of HIV-1 resistance to protease. A technology was worked out, which is based on the hybridization of a fluorescence-labeled amplified fragment of the pol gene of the HIV-1 provirus DNA with a set of specific oligonucleotides immobilized in 3-D hydrogel pads of the biological microchip. The biochip was used to analyze 115 samples of the subtype-1 provirus HIV-1 DNA isolated from untreated IDUs and their sexual partners in 15 regions of former USSR countries. Substitution of Val/IIe in position 77 of protease (V771) is known as secondary mutation of resistance to Nelfinavir detected in 55 (47.8%) of 115 HIV-1 variations. Its first appearance was registered in a patient with HIV in April 1997 in Tver, where its carrying variant caused an HIV outbreak. It is demonstrated that the V771-substitution variant, that dominates in Moscow, caused outbreaks in Irkutsk and Yekaterinburg and spread into separate districts of Perm and Perm Region. At the same time, no V771 HIV-1 was detected in any of the HIV studied cases diagnosed before 1998 in Moldova, Ukraine and Rostov Region.

[The genetic variability of the protease-encoding region in HIV-1 A isolates and in CRF03_AB recombinants as observed in the CIS territory]. / Geneticheskaia izmenchivost' oblasti, kodiruiushchei proteazu, u izoliatov VICH-1 podtipa A i rekombinantov CRF03_AB na territorii SNG.

Protease-encoding nucleotide sequences of 27 HIV-1 variants isolated in Russia and other CIS countries from seropositive intravenous drug-users were analyzed. None of the above persons did ever take antiretroviral drugs. The nucleotide sequences were shown to belong to subtypes A and to be have a high degree of genetic homogeneity (0.00-3.23; mean--1.38 +/- 0.79). No isolates contained any primary mutations of resistance to protease inhibitors. At the same time, above one half of the isolates bore the V771 substitution, which, according to published data, is the secondary mutation of resistance that conditions a higher resistance to Nelfinavir. Moreover, the substitution was associated with 2 synonymous mutations in triplets 31 and 78, which denotes a single origin for all V771 variants.

[Identification of Mycobacterium tuberculosis strains and a simultaneous identification of their drug resistance by the hybridization method on oligonucleotide microchips]. / Opredelenie shtammov Mycobacterium tuberculosis s odnovremennym opredeleniem ikh lekarstvennoi ustoichivosti metodom gibridizatsii na oligonukleotidnykh mikrochipakh.

A method of multiplex polymerase chain reaction (PCR) with subsequent hyoridization on oligonucleotide microchips was worked out to identify the Mycobacterium tuberculosis complex and to determine simultaneously the bacterial sensitivity to 2 first-line drugs, i.e. rifampin and isoniazid. The method provides for detecting above 95% of rifampin-resistant and around 80% of isoniazid-resistant strains within 1 day.