The former Soviet Union republics have experienced an explosive human immunodeficiency virus type 1 (HIV-1) epidemic among injecting drug users (IDUs), consisting mainly of subtype A viruses originated from a point source (Bobkov et al.: AIDS Res Hum Retroviruses 1997;13:1195-1201). To determine whether new HIV-1 subtypes have entered the IDU population, 46 samples derived from IDUs in Russia (n = 39) and the Ukraine (n = 7) were genotyped by heteroduplex mobility assay (HMA). It was shown that 83% of IDU HIV-1 strains found in both countries belong to genetic subtype A. However, env subtype B was also found in 17% of cases. The sequence data showed a marked intrasubtype homogeneity of HIV-1 (the average means of interpatient genetic distance were 1.1 and 1.7% [in the gag gene] or 1.8 and 2.3% [in the env gene] for subtype A and subtype B, respectively), confirming the hypothesis of a point source of virus for each subtype variant. Moreover, recombinant gagA/envB variants originating from those two strains were also found in two samples collected in the Kaliningrad region of Russia. In conclusion, our results suggest that two strains of HIV-1 belonging to different genetic subtypes, A and B, as well as gagA/envB recombinants between genomes of these strains, are now circulating simultaneously among IDUs in the former Soviet Union.

During the period 1996-1997, three highly homogeneous variants of HIV-1 were identified, circulating among injecting drug users (IDUs) in the former Soviet Union republics. One of these belonged to HIV-1 genetic subtype A (IDU-A), another belonged to HIV-1 genetic subtype B (IDU-B) and the third was a recombinant between the first two variants (CRF03_AB). However, since 1997, the HIV-1 epidemic has affected an increasing number of geographic regions in Russia. This study was undertaken to survey the prevailing genetic variants and to estimate the current proportions of these three HIV-1 genetic subtypes in Russia. Blood samples were taken in 1999-2003 from 1090 HIV-infected individuals and analysed by gag/env HMA. The IDU-A variant was found to be the majority variant (89.7-100%) in 44 of 45 regions of the Russian Federation studied. The IDU-A variant was also found to spreading rapidly through heterosexual transmission in 1999-2003 (30/34, 88%). CRF03_AB predominates in the Kaliningrad region only (28/29, 96.6%). The IDU-B variant is currently of minor importance in the IDU epidemic but other European subtype B variants predominate among men having sex with men (18/18, 100%). Sequence analysis of the env V3 encoding regions derived from HIV-1 infected individuals in Yekaterinburg (the main centre of the HIV-1 epidemic in Russia in 2002-2003) showed that the IDU-A variant is still highly homogeneous. The mean pairwise nucleotide distance (n = 9) was 2.89 +/- 1.14 (range 1.36-6.14). However, the mean genetic distance between each sequence within the samples collected from the Yekaterinburg IDU-A variant subset and the IDU-A consensus is 2.51 +/- 1.06 (range 1.36-4.66) and considerably higher than in South Russia in 1996 (0.79 +/- 0.51, range 0.38-1.90). The current HIV-1 epidemic in Russia is almost entirely caused by a highly homogeneous A-subtype strain, which will influence vaccine development strategies and must be taken into account in the quality control of molecular tests for the diagnosis of HIV-1.

Epidemiological data have demonstrated rapid growth of HIV-1 infections among injecting drug users (IDUs) in the Ukraine and Russia, during 1996. Here we describe the results of genetic analysis of isolates derived from 12 HIV-1-infected IDUs in different sites of Russia and the Ukraine. The blood samples were taken within a 1- to 2-month period after the first HIV-1-positive test. The results of the heteroduplex mobility assay as well as gag/env phylogenetic analysis reveal that all sequences belong to gag/env genetic subtype A. Moreover, interpatient genetic distances between the nucleotide sequences encompassing the C2-V3, the V4-V5, and p17-encoding regions within this group were low (the average means were 0.9, 1.3, and 0.4%, respectively). These data show a marked homogeneity of HIV-1, probably spreading during primary infection. It is possible that the current epidemic of subtype A HIV-1 among IDUs in the former Soviet Union is caused by a point source exposure.

An explosive epidemic of human immunodeficiency virus type 1 (HIV-1) has been documented among injecting drug users (IDUs) in the former Soviet Union republics. In 1999, the two largest local IDU outbreaks of HIV-1 infection in the Russian Federation were registered in the Moscow and Irkutsk regions, where 13,004 HIV-1 cases were identified (44% of the total number of HIV-1 infections in Russia in 1999). To study the prevailing genetic variants and to estimate the genetic diversity of HIV-1 in these outbreaks, 60 samples from Moscow (n = 36) and from Irkutsk (n = 24) were analyzed using the gag/env heteroduplex mobility assay, and the env gp120 V3 encoding regions obtained from 23 individuals were sequenced. Both virus populations were highly homogeneous (the means of pairwise nucleotide distance were 1.75 +/- 0.83 and 2.35 +/- 1.59 for Irkutsk and Moscow, respectively), and similar to the subtype A viruses obtained earlier from IDUs in the former Soviet Union. The subtype A HIV-1 variant thus dominates in the largest HIV-1 outbreaks among IDUs in the Russian Federation.

HIV-genetic subtypes were analyzed in 130 subjects from the Russian Federation, by the HMA technique. Six subtypes were identified in heterosexuals, including A, B, C, D, G, and H; however, homosexual men were infected predominantly with the B subtype (33 of 35). The subtype A isolates were found in population of intravenous drug users. HMA successfully identifies 128/130 DNA samples; the phylogenetic analysis of the V1/V5 gp120 encoding region derived from another two samples demonstrated that these isolate belong to subtype H.

Disulfide bonding in the major proteins of influenza virus A, WSN strain, was studied by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels under reducing and nonreducing conditions. The electrophoretic behavior of the proteins correlated with their localization in the virions and their chemical composition. The internal proteins of the viral particles, i.e. matrix and nucleoproteins, were shown to contain a relatively small number of cysteine residues. Electrophoresis under nonreducing conditions yielded multiple forms of the proteins which could be discriminated by small but readily observable, reproducible differences in their migration rates in the gel. The multiplicity of the protein forms was caused by the formation of intramolecular disulfide bonds in matrix and nucleoproteins that arose during or after solubilization in sodium dodecyl sulfate. On the other hand, we failed to detect native interand intramolecular linkages in matrix and nucleoproteins. External glycoproteins of the virions (HA and NA) had, in contrast to the internal ones, a higher number of cysteine residues and native disulfide bonds. At least three disulfide linkages were revealed in HA and NA in our experiments. In uncleaved HA all of the linkages were intramolecular. In NA at least one disulfide bond linked two identical polypeptides into a dimer. It was established that the reduction of the different disulfide linkages in HA and NA required different concentrations of the reducing agent.

SUMMARYThe rate of protein synthesis in chicken embryo cells infected with Sendal virus 18 to 20 h previously was about two times greater than in mock-infected controls. At this time of infection six stable virus-induced proteins, four major structural proteins (P, NH, NP and M) and two non-structural proteins (28K and 6IK), were identified by electrophoresis in SDS-polyacrylamide gel of total cell extracts. The structural glycopeptide F was not detected in the infected cell extracts. Pulse-chase experiments showed that P, NP, M and 28K proteins either did not undergo any post-translational processing or the processing occurred very rapidly. By contrast, a glycopeptide NH was apparently derived from one of two unstable precursors, 69K or 63K, which were revealed only after a short pulse. The synthesis of virus-specific proteins appeared to be regulated since its rate varied for individual classes of proteins.In nucleocapsid-like particles isolated from infected cells two major structural proteins (P and NP) were found. A minor component with a very large tool. wt. was revealed in these particles as well as in the virus particle.

The stability of the human immunodeficiency virus type 1 (HIV-1) strain IIIB in drug solutions was studied. The data demonstrate that HIV-1 infectivity can be retained in drug solutions (e.g. , heroin, “Khanka,” and “Vint”) for long periods of time. This fact must be taken into account when designing health education programs for the prevention of HIV and AIDS in Eastern Europe