Medicine and Health Sciences Commons^™

Boosting Of Hiv Envelope Cd4 Binding Site Antibodies With Long Variable Heavy Third Complementarity Determining Region In The Randomized Double Blind Rv305 Hiv-1 Vaccine Trial, David Easterhoff, M. Anthony Moody, Daniela Fera, Hao Cheng, Margaret Ackerman

Dartmouth Scholarship

The canary pox vector and gp120 vaccine (ALVAC-HIV and AIDSVAX B/E gp120) in the RV144 HIV-1 vaccine trial conferred an estimated 31% vaccine efficacy. Although the vaccine Env AE.A244 gp120 is antigenic for the unmutated common ancestor of V1V2 broadly neutralizing antibody (bnAbs), no plasma bnAb activity was induced. The RV305 (NCT01435135) HIV-1 clinical trial was a placebo-controlled randomized double-blinded study that assessed the safety and efficacy of vaccine boosting on B cell repertoires. HIV-1- uninfected RV144 vaccine recipients were reimmunized 6–8 years later with AIDSVAX B/E gp120 alone, ALVAC-HIV alone, or a combination of ALVAC-HIV and AIDSVAX B/E gp120 …

Directed Evolution Of A Yeast-Displayed Hiv-1 Sosip Gp140 Spike Protein Toward Improved Expression And Affinity For Conformational Antibodies, Sebastian K. Grimm, Michael B. Battles, Margaret E. Ackerman

Dartmouth Scholarship

Design of an envelope-based immunogen capable of inducing a broadly neutralizing anti- body response is thought to be key to the development of a protective HIV-1 vaccine. How- ever, the broad diversity of viral variants and a limited ability to produce native envelope have hampered such design efforts. Here we describe adaptation of the yeast display sys- tem and use of a combinatorial protein engineering approach to permit directed evolution of HIV envelope variants. Because the intrinsic instability and complexity of this trimeric glyco- protein has greatly impeded the development of immunogens that properly represent the structure of native envelope, …

Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman

Dartmouth Scholarship

Understanding the coordination between humoral and cellular immune responses may be the key to developing protective vaccines, and because genetic studies of long-term HIV-1 nonprogressors have associated specific HLA-B alleles with spontaneous control of viral replication, this subject group presents an opportunity to investigate relationships between arms of the adaptive immune system. Given evidence suggesting that cellular immunity may play a role in viral suppression, we sought to determine whether and how the humoral immune response might vary among controllers. Significantly, Fc-mediated antibody effector functions have likewise been associated with durable viral control. In this study, we compared the effector …

Interactions Of Peptide Triazole Thiols With Env Gp120 Induce Irreversible Breakdown And Inactivation Of Hiv-1 Virions, Arangassery Bastian, Mark Contarino, Lauren D. Bailey, Rachna Aneja, Diogo Rodrigo Magalhaes Moreira, Kevin Freedman, Karyn Mcfadden, Caitlin Duffy, Ali Emileh

Dartmouth Scholarship

Background: We examined the underlying mechanism of action of the peptide triazole thiol, KR13 that has been shown previously to specifically bind gp120, block cell receptor site interactions and potently inhibit HIV-1 infectivity.

Results: KR13, the sulfhydryl blocked KR13b and its parent non-sulfhydryl peptide triazole, HNG156, induced gp120 shedding but only KR13 induced p24 capsid protein release. The resulting virion post virolysis had an altered morphology, contained no gp120, but retained gp41 that bound to neutralizing gp41 antibodies. Remarkably, HIV-1 p24 release by KR13 was inhibited by enfuvirtide, which blocks formation of the gp41 6-helix bundle during membrane fusion, while …

Breast Milk From Tanzanian Women Has Divergent Effects On Cell-Free And Cell-Associated Hiv-1 Infection In Vitro, Magdalena A. Lyimo, Matilda Ngarina Mosi, Molly L. Housman, Muhammad Zain-Ul-Abideen, Frederick V. Lee, Alexandra L. Howell, Ruth I. Connor

Dartmouth Scholarship

Transmission of HIV-1 during breastfeeding is a significant source of new pediatric infections in sub-Saharan Africa. Breast milk from HIV-positive mothers contains both cell-free and cell-associated virus; however, the impact of breast milk on HIV-1 infectivity remains poorly understood. In the present study, breast milk was collected from HIV-positive and HIV-negative Tanzanian women attending antenatal clinics in Dar es Salaam. Milk was analyzed for activity in vitro against both cell-free and cell-associated HIV-1. Potent inhibition of cell-free R5 and X4 HIV-1 occurred in the presence of milk from all donors regardless of HIV-1 serostatus. Inhibition of cell-free HIV-1 infection positively …

Selective Impact Of Hiv Disease Progression On The Innate Immune System In The Human Female Reproductive Tract, Timothy Lahey, Mimi Ghosh, John V. Fahey, Zheng Shen, Lucy R. Mukura, Yan Song, Susan Cu-Uvin, Kenneth H. Mayer, Peter F. Wright, John C. Kappes, Christina Ochsenbauer, Charles R. Wira

Dartmouth Scholarship

Background: We have previously demonstrated intrinsic anti-HIV activity in cervicovaginal lavage (CVL) from HIV-infected women with high CD4 counts and not on antiretroviral therapy. However, the impact of HIV disease progression on CVL innate immune responses has not been delineated.

Methods: CVL from 57 HIV-infected women not on antiretroviral therapy were collected by washing the cervicovaginal area with 10 ml of sterile normal saline. We characterized subject HIV disease progression by CD4 count strata: >500 cells/µl, 200-500 cells/µl, or <200 cells/µl of blood. To assess CVL anti-HIV activity, we incubated TZM-bl cells with HIV plus or minus CVL. Antimicrobials, cytokines, chemokines and anti-gp160 HIV IgG antibodies were measured by ELISA and Luminex.

Uterine Epithelial Cell Regulation Of Dc-Sign Expression Inhibits Transmitted/Founder Hiv-1 Trans Infection By Immature Dendritic Cells, Daniel O. Ochiel, Christina Ochsenbauer, John C. Kappes, Mimi Ghosh, John V. Fahey, Charles R. Wira

Dartmouth Scholarship

Background:

Sexual transmission accounts for the majority of HIV-1 infections. In over 75% of cases, infection is initiated by a single variant (transmitted/founder virus). However, the determinants of virus selection during transmission are unknown. Host cell-cell interactions in the mucosa may be critical in regulating susceptibility to infection. We hypothesized in this study that specific immune modulators secreted by uterine epithelial cells modulate susceptibility of dendritic cells (DC) to infection with HIV-1.

Methodology/Principal Findings:

Here we report that uterine epithelial cell secretions (i.e. conditioned medium, CM) decreased DC-SIGN expression on immature dendritic cells via a transforming growth factor beta (TGF-β) …

Anti-Hiv Activity In Cervical-Vaginal Secretions From Hiv-Positive And -Negative Women Correlate With Innate Antimicrobial Levels And Igg Antibodies, Mimi Ghosh, John V. Fahey, Zheng Shen, Timothy Lahey, Susan Cu-Uvin, Zhijin Wu, Kenneth Mayer, Peter F. Wright, John C. Kappes, Christina Ochsenbauer, Charles R. Wira

Dartmouth Scholarship

Background: We investigated the impact of antimicrobials in cervicovaginal lavage (CVL) from HIV(+) and HIV(2) women on target cell infection with HIV. Since female reproductive tract (FRT) secretions contain a spectrum of antimicrobials, we hypothesized that CVL from healthy HIV(+) and (2) women inhibit HIV infection.

Methodology/Principal Findings: CVL from 32 HIV(+) healthy women with high CD4 counts and 15 healthy HIV(2) women were collected by gently washing the cervicovaginal area with 10 ml of sterile normal saline. Following centrifugation, anti- HIV activity in CVL was determined by incubating CVL with HIV prior to addition to TZM-bl cells. Antimicrobials and …

Improving Outcomes In Infants Of Hiv-Infected Women In A Developing Country Setting, Francine Noel, Sapna Mehta, Yuwei Zhu, Patricia De Matteis Rouzier, Abdias Marcelin, Jian R. Shi, Claudine Nolte, Linda Severe, Marie Marcelle Deschamps, Daniel W. Fitzgerald, Warren D. Johnson, Peter F. Wright, Jean W. Pape

Dartmouth Scholarship

Background: Since 1999 GHESKIO, a large voluntary counseling and HIV testing center in Port-au-Prince, Haiti, has had an ongoing collaboration with the Haitian Ministry of Health to reduce the rate of mother to child HIV transmission. There are limited data on the ability to administer complex regimens for reducing mother to child transmission and on risk factors for continued transmission and infant mortality within programmatic settings in developing countries.

Methods and Findings: We analyzed data from 551 infants born to HIV-infected mothers seen at GHESKIO, between 1999 and 2005. HIV-infected mothers and their infants were given “short-course” monotherapy with antiretrovirals …

Innate Antiviral Response Targets Hiv-1 Release By The Induction Of Ubiquitin-Like Protein Isg15, Atsushi Okumura, Gengshi Lu, Ian Pitha-Rowe, Paula M. Pitha

Dartmouth Scholarship

The goal of this study was to elucidate the molecular mechanism by which type I IFN inhibits assembly and release of HIV-1 virions. Our study revealed that the IFN-induced ubiquitin-like protein ISG15 mimics the IFN effect and inhibits release of HIV-1 virions without having any effect on the synthesis of HIV-1 proteins in the cells. ISG15 expression specifically inhibited ubiquitination of Gag and Tsg101 and disrupted the interaction of the Gag L domain with Tsg101, but conjugation of ISG15 to Gag or Tsg101 was not detected. The inhibition of Gag-Tsg101 interaction was also detected in HIV-1 infected, IFN-treated cells. Elimination …

Human Immunodeficiency Virus Type 1 Infection Of Cells And Tissues From The Upper And Lower Human Female Reproductive Tract, Alexandra L. Howell, Robert D. Edkins, Sherry E. Rier, Grant R. Yeaman, Judy E. Stern, Michael W. Fanger, Charles R. Wira

Dartmouth Scholarship

Viable tissue sections and isolated cell cultures from the human fallopian tube, uterus, cervix, and vaginal mucosa were examined for susceptibility to infection with human immunodeficiency virus type 1 (HIV-1). We examined infectivity by using the monocytotropic strain HIV-1_JR-FLand several primary isolates of HIV-1 obtained from infected neonates. HIV-1 infection was measured by p24 production in short-term culture and by immunofluorescence detection of HIV-1 Nef and p24 proteins by laser scanning confocal microscopy. Three-color immunofluorescence was used to phenotype HIV-infected cells within tissue sections from each site. Our findings indicate that epithelial, stromal, and dendritic cells and cells …