Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: Genotypic and functional properties of early infant HIV-1 envelopes. | Kishko et al. Retrovirology 2011 8 67 http content 8 1 67 RETROVIROLOGY RESEARCH Open Access Genotypic and functional properties of early infant HIV-1 envelopes Michael Kishko1 Mohan Somasundaran2 Frank Brewster2 John L Sullivan2 3 Paul R Clapham3 and Katherine Luzuriaga2 3 Abstract Background Understanding the properties of HIV-1 variants that are transmitted from women to their infants is crucial to improving strategies to prevent transmission. In this study 162 full-length envelope env clones were generated from plasma RNA obtained from 5 HIV-1 Clade B infected mother-infant pairs. Following extensive genotypic and phylogenetic analyses 35 representative clones were selected for functional studies. Results Infant quasispecies were highly homogeneous and generally represented minor maternal variants consistent with transmission across a selective bottleneck. Infant clones did not differ from the maternal in env length or glycosylation. All infant variants utilized the CCR5 co-receptor but were not macrophage tropic. Relatively high levels IC50 100 pg ml of autologous maternal plasma IgG were required to neutralize maternal and infant viruses however all infant viruses were neutralized by pooled sera from HIV-1 infected individuals implying that they were not inherently neutralization-resistant. All infant viruses were sensitive to the HIV-1 entry inhibitors Enfuvirtide and soluble CD4 none were resistant to Maraviroc. Sensitivity to human monoclonal antibodies 4E10 2F5 b12 and 2G12 varied. Conclusions This study provides extensive characterization of the genotypic and functional properties of HIV-1 env shortly after transmission. We present the first detailed comparisons of the macrophage tropism of infant and maternal env variants and their sensitivity to Maraviroc the only CCR5 antagonist approved for therapeutic use. These findings may have implications for improving approaches to prevent mother-to-child HIV-1 transmission. Background .
