HIV is most commonly acquired by mucosal route during sexual intercourse. Therefore, blocking this means of transmission will rapidly decrease HIV incidence worldwide. In the first days following mucosal exposure HIV must overcome numerous barriers offering a window of opportunity to act before HIV establishes infection. Unfortunately, the critical events that take place after viral exposure are poorly understood. We propose that HSV-2 influences these early events by modulating the mucosal microenvironment and, to explore how, we will use our recently established macaque model of HSV-2 infection in combination with a model of SHIV vaginal transmission. This combination constitutes a new powerful tool to study the earliest stages of SHIV infection in a controlled manner, explore the effect of HSV-2 and identify the events that influence transmission. Interestingly, we found that rectal HSV-2 infection increases the percentage of ?4?7highCD4+ T cells in the site of infection (rectal tissue), blood, and draining lymph nodes. And in earlier wors we described a specific interaction between the HIV/SIV envelope and ?4?7. Mucosal CD4+ T cells expressing high levels of this receptor (?4?7high) constitute a preferential target for HIV infection. Recent data has further indicated that early-transmitted viruses exhibit increased reactivity for ?4?7 (compared to chronic isolates and to their reactivity for CD4), suggesting that this molecule is especially important during the initial stages of infection. Additionally, we foun that dendritic cells (DCs) infected with HSV-2 in-vitro expand the ?4?7high subset of CD4+ T cells in co-culture and increase HIV infection in these mixtures. Thus, we hypothesize that HSV-2 influences DC function within the cervico-vaginal tissue and that this, in turn, increases the presence of ?4?7highCD4+ T cells in the mucosa. We intend to use HSV-2 as a tool to dissect the role of ?4?7highCD4+ T cells during early events of HIV transmission across the cervico-vaginal mucosa. We will study how HSV-2 modulates T cell and DC biology within the cervico-vaginal tissues (cell migration, activation, phenotype) to determine how this influences susceptibility to repeated low-dose SHIVSF162P3 vaginal challenge. Moreover, using a drug that specifically inhibits HIV-envelope binding to ?4?7 versus a mutant virus that has increased affinity for ?4?7 we will further demonstrate the importance of the ?4?7-HIV interaction in the onset of SHIV infection. These studies will provide critical insight into the role of ?4?7 in the earliest moments of HIV infection across the cervico-vaginal mucosa and how this is influenced by HSV-2 infection, opening up novel approaches to tackle HIV spread.

Public Health Relevance

We believe that the receptor ?4?7, present on cells preferentially infected by HIV, has a critical role in HIV-1 transmission. In order prove our hypothesis we will use three different strategies, all of them involving a monkey model of HIV infection. We will study the effect of increasing the % of cells T expressing this receptor in the genital tract right before transmission, we will test a drug that blocks HIV interaction with ?4?7 and we will compare the infections of 2 HIV viruses that differ only in the strength of their binding to ?4?7. Our work aims to identify a novel target for blocking HIV transmission.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI098546-02
Application #
8440738
Study Section
AIDS Immunology and Pathogenesis Study Section (AIP)
Program Officer
Sharma, Opendra K
Project Start
2012-03-15
Project End
2017-02-28
Budget Start
2013-03-01
Budget End
2014-02-28
Support Year
2
Fiscal Year
2013
Total Cost
$677,582
Indirect Cost
$151,716
Name
Population Council
Department
Type
DUNS #
071050090
City
New York
State
NY
Country
United States
Zip Code
10017
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Aravantinou, Meropi; Frank, Ines; Arrode-Bruses, Geraldine et al. (2017) A model of genital herpes simplex virus Type 1 infection in Rhesus Macaques. J Med Primatol 46:121-128
Arrode-Brusés, Géraldine; Goode, Diana; Kleinbeck, Kyle et al. (2016) A Small Molecule, Which Competes with MAdCAM-1, Activates Integrin ?4?7 and Fails to Prevent Mucosal Transmission of SHIV-SF162P3. PLoS Pathog 12:e1005720
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Goode, Diana; Truong, Rosaline; Villegas, Guillermo et al. (2014) HSV-2-driven increase in the expression of ?4?7 correlates with increased susceptibility to vaginal SHIV(SF162P3) infection. PLoS Pathog 10:e1004567
Goode, Diana; Aravantinou, Meropi; Jarl, Sebastian et al. (2014) Sex hormones selectively impact the endocervical mucosal microenvironment: implications for HIV transmission. PLoS One 9:e97767