[Genetic characteristics of HIV-1 subtype G reverse transcriptase gene].

The paper presents data of a study of the structure of reverse transcriptase gene in the population infected with HIV subtype G formed during the 1989 HIV infection outbreak in the North-Caucasian region. The authors analyzed 3 samples obtained in 1993-1994 and 17 samples taken in 2000-2001. The phylogenetic analysis indicated that polymerase of the test virus variants belonged to HIV-1 subtype G. The mutations occurring with azidothymidine therapy did not differ from those in subtype B. Analysis of the mutations of resistance to other nucleoside and non-nucleoside reverse transcriptase inhibitors did not show great differences from subtype B either.

[Prevalence of mutations of resistance to HIV-I reverse transcriptase inhibitors among HIV-infected patients in the Southern Federal District].

To study the regularities in the spread of drug-resistant HIV-1 strains among HIV-infected patients in the Southern Federal District (SFD), the HIV-1 pol gene site encoded for reverse transcriptase was sequenced in the samples taken from 22 HIV-infected SFD patients who received or did not receive antiretroviral therapy (ARVT). Analysis of the primary sequences of the HIV-1 pol gene in SFD patients untreated with antiviral agents revealed the absence of both primary and secondary mutations of resistance to a nucleoside reverse transcriptase inhibitor (NRTI) and a non-nucleoside reverse transcriptase inhibitor (NNRTI). The group of patients receiving antiviral treatment was found to have different drug resistance mutations in the HIV-1 pol gene: K70R, M184V, K219Q, T215Y/F, L74V, etc. Moreover, the patients on ARVT had higher CD4 T lymphocyte levels and higher immunoregulatory index in the presence of significantly lower HIV replication than the untreated patients. The authors make recommendations how to study HIV resistance in patients who are to be treated and are receiving ARVT and advise to monitor the spread of drug-resistant HIV strains in the SFD.

[Analysis of changes in the gp120 V3 region as observed in some patients with HIV infected from a common infection source]. / Analiz izmenchivosti oblasti V3 gp120 u otdel'nykh patsientov v kogorte VICH-infitsirovannykh, imeiushchikh edinyi istochnik zarazheniia.

HIV-1 genome regions encoding the gp120 V3 part were sequenced in samples isolated from persons belonging to the category of those infected in the Rostov-Elista outbreak and having the common infection source. Samples were obtained from 5 patients in 1992 and in 2001. A total of 27 sequences obtained in 1992 and 35 sequences obtained in 2001, 2 to 8 sequences for each patient, were analyzed. The diversity level of V3 sequences made, in some patients, 2.2% in 1992 and went up to 4.2% in 2001 samples (p < 0.07). The ratio between the synonymous and non-synonymous substitutions was determined for the gp120 V3 region. The mean ratio value made 0.12 in 1992 samples and 0.23 in 2001 samples. The obtained data confirm the assumption, made previously in a population analysis, on the evolution of the gp120 V3 epitope towards substitution of the Lg initial structure in positions 14 and 15 (through intermediate stages represented by the IG and FG structures) for the FA structure.

[HIV-1 serotyping of V3-mimicking peptides circulating in the Republic of Tajikistan among intravenous drug users]. / Serotipirovanie na osnove V3-imitiruiushchikh peptidov variantov VICH-1, tsirkuliruiushchikh v Respublike Tadzhikistan sredi lits, upotrebliaiushchikh narkotiki vnutrivenno.

The paper summarizes the results of HIV-1 serotyping by using 56 positive sera collected in the territory of the Republic of Tajikistan (RT) from intravenous drug users (IVDU). It was made by solid-phase ELISA based on synthetic peptides, mimicking different variants of the apical epitope of the HIV-1 gp120 V3-loop. Two types of conjugates, those specific to human IgG and IgA, were used to detect the immune complexes. Serotypes, as determined according to IgG and IgA-based ELISA, coincided, however, the latter were proven to be more suitable for serotyping. There is a high level of HIV-1 serotype heterogeneity among IVDU in RT; altogether, 4 serotypes were identified, i.e. B (10%), B+A/C (18%), A/C (20%) and A/C+B (52%). The modern serotype HIV-1 diversity in RT resembles the epidemiologic situation in the territory of the former USSR as observed in the late 80-ies-early 90-ies of the last century.

[A retrospective analysis of population type variability of the region V3 gp120 in HIV infected patients with a unified infection focus]. / Retrospektivnyi analiz populiatsionnoi izmenchivosti oblasti V3 gp120 v kogorte VICH-infitsirovannykh, imeiushchikh edinyi istochnik zarazheniia.

Regions of HIV-1 genome, encoding the V3 gp120 region, were sequenced in materials that were sampled from persons belonging to the category of individuals infected from a single source during the Rostov-Elista outbreak. The samples were obtained in 1991-1992 (10 pieces) and in 2000-2001 (16 pieces), which amounts to 8% and 13%, respectively, of a total number of patients infected by the beginning of 1990. It was established that the level of the population variability of amino-acid sequences in region V3 amounted, in 1991-1992, to 5.2% and increased to 9.1% in the samples of 2000-2001. A comparison of amino-acid sequences in region V3 from the collections of 1991-1992 and of 2000-2001 revealed the below amino-acid substitutions: from Ser13 to His, from Ley14 to Phe, from Phe to Ley and from Ley to Ala. An analysis of V3 B-epitope showed that the basic trend of its evolution consists in reciprocal transitions of L to F in position 14 and of F to L in position 20. Such substitutions ensure further changes at the "top" of the V3-loop from GPG to APG.