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Browsing by Author "Arney, Leslie."

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    CAPRISA 004 tenofovir microbicide trial: no impact of tenofovir gel on the HIV transmission bottleneck.
    (Oxford University Press., 2011) Valley-Omar, Ziyaad.; Sibeko, Sengeziwe.; Anderson, Jeffrey A.; Goodier, Sarah A.; Werner, Lise.; Arney, Leslie.; Naranbhai, Vivek.; Treurnicht, Florette K.; Abrahams, Melissa-Rose.; Bandawe, Gama P.; Swanstrom, Ronald.; Abdool Karim, Salim Safurdeen.; Abdool Karim, Quarraisha.; Williamson, Carolyn.
    Alterations of the genital mucosal barrier may influence the number of viruses transmitted from a human immunodeficiency virus–infected source host to the newly infected individual. We used heteroduplex tracking assay and single-genome sequencing to investigate the effect of a tenofovir-based microbicide gel on the transmission bottleneck in women who seroconverted during the CAPRISA 004 microbicide trial. Seventy-seven percent (17 of 22; 95% confidence interval [CI], 56%–90%) of women in the tenofovir gel arm were infected with a single virus compared with 92% (13 of 14; 95% CI, 67%–>99%) in the placebo arm (P = .37). Tenofovir gel had no discernable impact on the transmission bottleneck.
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    Comparison of viral env proteins from acute and chronic infections with subtype C human immunodeficiency virus type 1 identifies differences in glycosylation and CCR5 utilization and suggests a new strategy for immunogen design.
    (American Society for Microbiology., 2013) Ping, Li-Hua.; Joseph, Sarah B.; Anderson, Jeffrey A.; Abrahams, Melissa-Rose.; Salazar-Gonzalez, Jesus F.; Kincer, Laura P.; Treurnicht, Florette K.; Arney, Leslie.; Ojeda, Suany.; Zhang, Ming.; Keys, Jessica.; Potter, E. Lake.; Chu, Haitao.; Moore, Penelope L.; Salazar-Gonzalez, Maria.; Iyer, Shilpa.; Jabara, Cassandra.; Kirchherr, Jennifer.; Mapanje, Clement.; Ngandu, Nobubelo K.; Seoighe, Cathal.; Hoffman, Irving F.; Gao, Feng.; Tang, Yuyang.; Labranche, Celia.; Lee, Benhur.; Saville, Andrew.; Vermeulen, Marion.; Fiscus, Susan A.; Morris, Lynn.; Abdool Karim, Salim Safurdeen.; Haynes, Barton F.; Shaw, George M.; Korber, Bette T. M.; Hahn, Beatrice H.; Cohen, Myron S.; Montefiori, David Charles.; Williamson, Carolyn.; Swanstrom, Ronald.
    Understanding human immunodeficiency virus type 1 (HIV-1) transmission is central to developing effective prevention strategies, including a vaccine.We compared phenotypic and genetic variation in HIV-1 env genes from subjects in acute/early infection and subjects with chronic infections in the context of subtype C heterosexual transmission.We found that the transmitted viruses all used CCR5 and required high levels of CD4 to infect target cells, suggesting selection for replication in T cells and not macrophages after transmission. In addition, the transmitted viruses were more likely to use a maraviroc-sensitive conformation of CCR5, perhaps identifying a feature of the target T cell.We confirmed an earlier observation that the transmitted viruses were, on average, modestly under-glycosylated relative to the viruses from chronically infected subjects. This difference was most pronounced in comparing the viruses in acutely infected men to those in chronically infected women. These features of the transmitted virus point to selective pressures during the transmission event.We did not observe a consistent difference either in heterologous neutralization sensitivity or in sensitivity to soluble CD4 between the two groups, suggesting similar conformations between viruses from acute and chronic infection. However, the presence or absence of glycosylation sites had differential effects on neutralization sensitivity for different antibodies.We suggest that the occasional absence of glycosylation sites encoded in the conserved regions of env, further reduced in transmitted viruses, could expose specific surface structures on the protein as antibody targets.