[Study of biological properties of HIV-1 variants resistant to antiretroviral preparations].

AIM: Separation of HIV-1 isolates from HIV infected patients who had received antiretroviral therapy courses. Analysis of genetic and replicative properties of the separated isolates, study of pol gene mutation stability sustentation that is responsible for the emergence of drug resistance. MATERIALS AND METHODS: HIV isolate separation was carried out by co-cultivation ofperipheral blood mononuclears of HIV infected patients with previously stimulated phytohemagglutinin cells of healthy donors. Virus replication was evaluated by the level of p24 virus specific protein accumulation determined in enzyme immunoassay. HIV-1 subtype identification, detection of HIV-1 genome mutations were carried out by pol gene nucleotide sequence determination and subsequent analysis of the data obtained - by using specialized program resources. RESULTS: 14 infectious HIV-1 subtype A, B and CRF02_AG isolates were separated containing various sets of mutations determining resistance to widely used in clinical practice nucleoside and non-nucleoside reversetranscriptase inhibitors. Comparative analysis of mutation specter detected in HIV-1 variant genomes before isolation and after their cultivation showed that during HIV-1 cultivation in mononuclear blood cells without the addition of antiretroviral preparations not only partial loss of mutations is observed but also emergence of new drug resistance mutations; and most of the mutation causing virus resistance to antiretroviral preparations remain. CONCLUSION: High reproductive properties of the HIV-1 isolates separated allow to use them to evaluate effectiveness of the drugs being developed against HIV-1 resistant to antiretroviral preparations.

[Prevalence of mutations responsible for resistance to antiretroviral preparations among HIV-1 variants circulating in Novosibirsk region].

AIM: Analyze the diversity and prevalence of mutations in human immunodeficiency virus type 1 (HIV-1) genome emerging in response to antiretroviral therapy isolated from HIV-infected individuals of Novosibirsk region in 2010, 2011. MATERIALS AND METHODS: Detection of mutations in HIV-1 genome responsible for the resistance to. antiretroviral preparations (ARVP) was carried out by determination of pol gene nucleotide sequence and subsequent analysis ofthe data obtained by program HIVdb: Genotypic Resistance Interpretation Algorithm. RESULTS: HIV-1 resistance mutations to antiretroviral preparations were detected in 23.6% of the total number of the studied samples. The most prevalent mutations are those conditioning resistance to nucleoside and non-nucleoside reverse transcriptase inhibitors (M184V, Y181C and K103N). In studies of HIV-1 isolated from 4 patients who had not received antiretroviral therapy (ARVT) transmission of HIV-1 resistant to various groups of preparations was detected. CONCLUSION: The detected facts of ARVP resistant HIV-1 circulation among patients who had not received ARVT and the data obtained on the mutations emerging in response to therapy underline the relevance of administration of HIV-1 resistance profile study during both decrease of ARVT effectiveness and primary administration of therapy to HIV infected patients.

[Molecular-genetic characteristic of HIV-1 A and B subtypes variants isolated in Novosibirsk region].

AIM: Study phylogenetic interconnections of HIV-1 subtype A and B variants circulating in Novosibirsk region (NSR). MATERIALS AND METHODS: 268 HIV-1 variants isolated in 2007 - 2010 from blood samples of HIV infected patients in NSR, Samara, Congo and Moscow. HIV-1 variant genotyping was performed by analysis of 1.3 kb long pol gene nucleotide sequences. Phylogenetic analysis of nucleotide sequences was carried out by program Mega version 4.1 by constructing phylogenetic trees by nearest neighbor method. Nucleotide distances were calculated by Kimura method. RESULTS: The studied HIV-1 subtype B variants form separate phylogenetic groups with a low HIV-1 nucleotide sequence homology level combined based on territorial principle and/or time of HIV infection in a territory but not possessing interconnection with a specific population risk group. Subtype A HIV-1 is a fairly homogenous monophyletic group. Phylogenetic differences during studies of HIV-1 isolated from risk group patients - injection drugs users and individuals infected through sexual contacts were not detected. HIV variants isolated from patients infected in Moscow and Samara generally grouped with HIV variants circulating in the European part of Russia. CONCLUSION: An independent circulation of genetically separate HIV-1 subtype B groups is observed on the territory of siberian region which is a result of multiple independent introductions of distant variants of the virus. The confirmed limited spread of this HIV-1 genetic variant with a subsequent territorial separateness creates a possibility of formation of genetically different virus populations. The studies of subtype A viruses performed confirm the high level of homogeneity detected earlier in other Russia territories of HIV-1 belonging to this genetic variant. Monophyly of subtype A HIV variants is explained by imposition of 2 factors - territorial mobility of the population inside the country and lack of specific transmission routes for HIV-1 subtype A.