Dynamic variation of HIV-1 CRF07_BC env gene in early HIV-1 infection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the evolution of HIV-1 CRF07_BC envelope, we performed a longitudinal study on two patients during their early HIV-1 infection.</p><p><b>METHODS</b>RNA was extracted from the plasma of the individuals and the C2-C5 fragments of the gp120 gene of HIV-1 were amplified by RT-PCR. Purified DNA segments were inserted into T easy vector and transformed into E. coli Top 10 competent cells. Positive clones were identified by blue-white screening, confirmed by PCR and sequenced by ABI 3700.</p><p><b>RESULTS</b>The samples were collected from the patients every 6 months from seroconversion time. The genetic diversity and divergence in env gene showed consistent increases over time. Our sequence analysis also revealed obvious non-synonymous change in env C1, C3 and V4 regions among these samples.</p><p><b>CONCLUSION</b>The results support the concept that the consistent pattern of viral evolution existed during early phase of HIV-1 infection. C1, C3 and V4 region of env gene may be mainly immunological target during AIDS progression.</p>

Subtype and sequence analysis of gag and env genes among HIV-1 strains circulating in Beijing residents during 2006 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the subtype distribution and the prevalence of sequence characteristics of HIV-1 strains in Beijing residents during 2006 and to analyze the relationship between distribution of HIV-1 subtypes and transmission routines.</p><p><b>METHODS</b>Blood samples from 32 new confirmed HIV-1 infected individuals from Beijing residents in 2006 and separated plasma specimens were collected. RNAs were extracted and the gag and env gene were amplified by RT-PCR and nest-PCR. PCR products were sequenced directly and phylogenetic analyses of gag and env gene were performed using the MEGA2 software.</p><p><b>RESULTS</b>Among 32 HIV-1 plasma samples, 22 gag and 4 env gene fragments were amplified and analyzed. Five HIV-1 subtypes or circulating recombinant forms(CRFs) of HIV-1 including Thai B (2 strains), B (9 strains), C (2 strains), CRF07_BC (5 strains), CRF01 AE (4 strains) were identified being circulated in Beijing. The gene divergences of gag gene inside the subtypes were 6.6%, 4.3%, 6.8%, 4.9% and 3.0% in subtype B, Thai B, C, CRF01_AE and CRF07_BC respectively. Subtypes B were predominant in Beijing, accounted for 40.9% among 22 samples.</p><p><b>CONCLUSION</b>Five HIV-1 subtypes were identified in Beijing and the surveillance of HIV-1 gene variation should be paid more attention to.</p>