Browsing by Author "Korber, Bette T. M."

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Broadly neutralizing antibodies targeting the HIV-1 envelope V2 apex confer protection against a clade C SHIV challenge.
(American Association for the Advancement of Science., 2017) Julg, Boris.; Tartaglia, Lawrence J.; Keele, Brandon F.; Wagh, Kshitij.; Pegu, Amarendra.; Sok, Devin.; Abbink, Peter.; Schmidt, Stephen D.; Wang, Keyun.; Chen, Xuejun.; Joyce, M. Gordon.; Georgiev, Ivelin S.; Choe, Misook.; Kwong, Peter D.; Doria-Rose, Nicole A.; Le, Khoa.; Louder, Mark K.; Bailer, Robert T.; Moore, Penelope L.; Korber, Bette T. M.; Seaman, Michael S.; Abdool Karim, Salim Safurdeen.; Morris, Lynn.; Koup, Richard A.; Mascola, John R.; Burton, Dennis R.; Barouch, Dan H.
Abstract available in pdf.
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.
Features of recently transmitted HIV-1 clade C viruses that impact antibody recognition : implications for active and passive immunization.
(Public Library of Science., 2016) Rademeyer, Cecilia.; Korber, Bette T. M.; Seaman, Michael S.; Giorgi, Elena E.; Thebus, Ruwayhida.; Robles, Alexander.; Sheward, Daniel J.; Wagh, Kshitij.; Garrity, Jetta.; Carey, Brittany R.; Gao, Hongmei.; Greene, Kelli M.; Tang, Haili.; Bandawe, Gama P.; Marais, Jinny C.; Diphoko, Thabo E.; Hraber, Peter.; Tumba, Nancy Lola.; Moore, Penelope L.; Gray, Glenda Elizabeth.; Kublin, James.; McElrath, Margaret Juliana.; Vermeulen, Marion.; Middelkoop, Keren.; Bekker, Linda-Gail.; Hoelscher, Michael.; Maboko, Leonard.; Makhema, Joseph.; Robb, Merlin L.; Abdool Karim, Salim Safurdeen.; Abdool Karim, Quarraisha.; Kim, Jerome H.; Hahn, Beatrice H.; Gao, Feng.; Swanstrom, Ronald.; Morris, Lynn.; Montefiori, David Charles.; Williamson, Carolyn.
Abstract available in PDF file.
Identification of broadly neutralizing antibody epitopes in 1 the HIV-1 envelope glycoprotein using evolutionary models.
(Virology Journal, 2013) Lacerda, Miguel.; Moore, Penelope L.; Ngandu, Nobubelo K.; Seaman, Michael.; Gray, Elin Solomonovna.; Murrell, Ben.; Krishnamoorthy, Mohan.; Nonyane, Molati.; Madiga, Maphuti C.; Wibmer, Constantinos Kurt.; Sheward, Daniel J.; Bailer, Robert T.; Gao, Hongmei.; Greene, Kelli M.; Abdool Karim, Salim Safurdeen.; Mascola, John R.; Korber, Bette T. M.; Montefiori, David Charles.; Morris, Lynn.; Williamson, Carolyn.; Seoighe, Cathal.
Background: Identification of the epitopes targeted by antibodies that can neutralize diverse HIV-1 strains can provide important clues for the design of a preventative vaccine. Methods: We have developed a computational approach that can identify key amino acids within the HIV-1 envelope glycoprotein that influence sensitivity to broadly cross-neutralizing antibodies. Given a sequence alignment and neutralization titers for a panel of viruses, the method works by fitting a phylogenetic model that allows the amino acid frequencies at each site to depend on neutralization sensitivities. Sites at which viral evolution influences neutralization sensitivity were identified using Bayes factors (BFs) to compare the fit of this model to that of a null model in which sequences evolved independently of antibody sensitivity. Conformational epitopes were identified with a Metropolis algorithm that searched for a cluster of sites with large Bayes factors on the tertiary structure of the viral envelope. Results: We applied our method to ID50 neutralization data generated from seven HIV-1 subtype C serum samples with neutralization breadth that had been tested against a multi-clade panel of 225 pseudoviruses for which envelope sequences were also available. For each sample, between two and four sites were identified that were strongly associated with neutralization sensitivity (2ln(BF) > 6), a subset of which were experimentally confirmed using site-directed mutagenesis. Conclusions: Our results provide strong support for the use of evolutionary models applied to cross-sectional viral neutralization data to identify the epitopes of serum antibodies that confer neutralization breadth.
Optimal combinations of broadly neutralizing antibodies for prevention and treatment of HIV-1 clade C infection.
(Public Library of Science., 2016) Wagh, Kshitij.; Bhattacharya, Tanmoy.; Williamson, Carolyn.; Robles, Alexander.; Bayne, Madeleine.; Garrity, Jetta.; Rist, Michael.; Rademeyer, Cecilia.; Yoon, Hyejin.; Lapedes, Alan.; Gao, Hongmei.; Greene, Kelli M.; Louder, Mark K.; Kong, Rui.; Abdool Karim, Salim Safurdeen.; Burton, Dennis R.; Barouch, Dan H.; Nussenzweig, Michel C.; Mascola, John R.; Morris, Lynn.; Montefiori, David Charles.; Korber, Bette T. M.; Seaman, Michael S.
Abstract available in PDF file.
Potent and broad HIV-neutralizing antibodies in memory B cells and plasma.
(American Association for the Advancement of Science., 2017) Williams, LaTonya D.; Ofek, Gilad.; Schätzle, Sebastian.; McDaniel, Jonathan R.; Lu, Xiaozhi.; Nicely, Nathan I.; Wu, Liming; Lougheed, Caleb S.; Bradley, Todd.; Louder, Mark K.; McKee, Krisha.; Bailer, Robert T.; O’Dell, Sijy.; Georgiev, Ivelin S.; Seaman, Michael S.; Parks, Robert J.; Marshall, Dawn J.; Anasti, Kara.; Yang, Guang.; Nie, Xiaoyan.; Tumba, Nancy Lola.; Wiehe, Kevin.; Wagh, Kshitij.; Korber, Bette T. M.; Kepler, Thomas B.; Alam, Shabnam Munir.; Morris, Lynn.; Kamanga, Gift.; Cohen, Myron S.; Bonsignori, Mattia.; Xia, Shi-Mao.; Montefiori, David Charles.; Kelsoe, Garnett.; Gao, Feng.; Mascola, John R.; Moody, Michael Anthony.; Saunders, Kevin O.; Liao, Hua-Xin.; Tomaras, Georgia D.; Georgiou, George.; Haynes, Barton F.
Abstract available in pdf.
Quantitating the multiplicity of infection with human immunodeficiency virus type 1 subtype C reveals a non-poisson distribution of transmitted variants.
(American Society for Microbiology., 2008) Abrahams, Melissa-Rose.; Anderson, Jeffrey A.; Giorgi, Elena E.; Seoighe, Cathal.; Mlisana, Koleka Patience.; Liu, Pinghuang.; Athreya, G. S.; Treurnicht, Florette K.; Keele, Brandon F.; Wood, N.; Salazar-Gonzalez, Jesus F.; Bhattacharya, Tanmoy.; Chu, Haitao.; Hoffman, Irving F.; Galvin, S.; Mapanje, Clement.; Kazembe, P.; Thebus, Ruwayhida.; Fiscus, Susan A.; Hide, Winston.; Cohen, Myron S.; Abdool Karim, Salim Safurdeen.; Haynes, Barton F.; Shaw, George M.; Hahn, Beatrice H.; Korber, Bette T. M.; Swanstrom, Ronald.; Williamson, Carolyn.
Identifying the specific genetic characteristics of successfully transmitted variants may prove central to the development of effective vaccine and microbicide interventions. Although human immunodeficiency virus transmission is associated with a population bottleneck, the extent to which different factors influence the diversity of transmitted viruses is unclear. We estimate here the number of transmitted variants in 69 heterosexual men and women with primary subtype C infections. From 1,505 env sequences obtained using a single genome amplification approach we show that 78% of infections involved single variant transmission and 22% involved multiple variant transmissions (median of 3). We found evidence for mutations selected for cytotoxic-T-lymphocyte or antibody escape and a high prevalence of recombination in individuals infected with multiple variants representing another potential escape pathway in these individuals. In a combined analysis of 171 subtype B and C transmission events, we found that infection with more than one variant does not follow a Poisson distribution, indicating that transmission of individual virions cannot be seen as independent events, each occurring with low probability. While most transmissions resulted from a single infectious unit, multiple variant transmissions represent a significant fraction of transmission events, suggesting that there may be important mechanistic differences between these groups that are not yet understood.
Vertical T cell immunodominance and epitope entropy determine HIV-1 escape.
(American Society for Clinical Investigation., 2012) Liu, Michael K. P.; Hawkins, Natalie.; Ritchie, Adam J.; Ganusov, Vitaly.; Whale, Victoria.; Brackenridge, Simon.; Li, Hui.; Pavlicek, Jeffrey W.; Cai, Fangping.; Abrahams, Melissa-Rose.; Treurnicht, Florette K.; Hraber, Peter.; Riou, Catherine.; Gray, Clive M.; Ferrari, Guido.; Tanner, Rachel.; Ping, Li-Hua.; Anderson, Jeffrey A.; Swanstrom, Ronald.; Cohen, Myron S.; Abdool Karim, Salim Safurdeen.; Haynes, Barton F.; Borrow, Persephone.; Perelson, Alan S.; Shaw, George M.; Hahn, Beatrice H.; Williamson, Carolyn.; Korber, Bette T. M.; Gao, Feng.; Self, Steven G.; McMichael, Andrew.; Goonetilleke, Nilu.
HIV-1 accumulates mutations in and around reactive epitopes to escape recognition and killing by CD8+ T cells. Measurements of HIV-1 time to escape should therefore provide information on which parameters are most important for T cell–mediated in vivo control of HIV-1. Primary HIV-1–specific T cell responses were fully mapped in 17 individuals, and the time to virus escape, which ranged from days to years, was measured for each epitope. While higher magnitude of an individual T cell response was associated with more rapid escape, the most significant T cell measure was its relative immunodominance measured in acute infection. This identified subject-level or “vertical” immunodominance as the primary determinant of in vivo CD8+ T cell pressure in HIV-1 infection. Conversely, escape was slowed significantly by lower population variability, or entropy, of the epitope targeted. Immunodominance and epitope entropy combined to explain half of all the variability in time to escape. These data explain how CD8+ T cells can exert significant and sustained HIV-1 pressure even when escape is very slow and that within an individual, the impacts of other T cell factors on HIV-1 escape should be considered in the context of immunodominance.