Male-to-female (M-*F) transmission of HIV is a major force driving expansion of the global AIDS epidemic, Our overall objective is to assess the potentially important role played by select viral and host factors in HIV transmission biology.
In Specific Aim 1, HIV transmission pairs will be used to test the hypothesis that the envelope proteins from viruses successfully transmitted to women differ from non-transmitted viruses by their fusogenic properties and/or target cell selectivity. Envelopes from transmitted viruses share common features including compact V1-V4 regions, decreased numbers of glycosylation sites, and a greater sensitivity to neutralizing antibodies. These viral envelopes may be imbued with special properties that favor virion fusion to target cells within the female reproductive mucosa.
In Specific Aim 2, biological features of recently identified fibrillar peptides in semen that can enhance HIV infection 10-100,000-fold will be tested. These peptides, termed semen enhancer of HIV infection (SEVI), are produced by endoproteolytic cleavage of prostatic acid phosphatase, a highly abundant semen protein. They enhance HIV infection by sharply increasing virion attachment to target cells. Our studies will test the hypothesis that SEVI propels M->F transmission of HIV and further that SEVI antagonists may impair HIV infection of women. Our studies specifically seek to: 1) identify the cellular protease(s) responsible for the generation of SEVI, 2) test whether SEVI enhances virion transcytosis, frans-infection, and cell-cell infection, 3) explore whether SEVI production varies among males and whether HIV infection alters SEVI levels, and 4) investigate novel approaches for inhibiting the action of SEVI. Effective SEVI antagonists could find application in future multi-component microbicides designed to prevent HIV transmission to women. This project will also interact extensively with Projects 2 and 3 of this P01 application. Viruses containing primary transmitted envelopes will be provided for use in these projects. Fusion assays will be performed collaboratively to monitor effects of progestin contraceptives, menopause, and microbicides on HIV target cells within female reproductive mucosa. Semen, SEVI, and SEVI antagonists will also be profiled for potential "harm" effects on endometrial and cervical mucosa. Together, the multiple lines of investigation described in Project 1 promise to expand our understanding of the molecular basis for M-?F transmission of HIV.

Public Health Relevance

An improved understanding of the molecular underpinnings of M->F transmission of HIV could result in new approaches for curbing HIV infection in women including rational approaches for development of female-controlled microbicides and prophylactic vaccines active at mucosal surfaces.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZAI1-TP-A)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
J. David Gladstone Institutes
San Francisco
United States
Zip Code
Cavrois, Marielle; Neidleman, Jason; Santiago, Mario L et al. (2014) Enhanced fusion and virion incorporation for HIV-1 subtype C envelope glycoproteins with compact V1/V2 domains. J Virol 88:2083-94
Roan, Nadia R; Liu, Haichuan; Usmani, Shariq M et al. (2014) Liquefaction of semen generates and later degrades a conserved semenogelin peptide that enhances HIV infection. J Virol 88:7221-34
Zirafi, Onofrio; Kim, Kyeong-Ae; Roan, Nadia R et al. (2014) Semen enhances HIV infectivity and impairs the antiviral efficacy of microbicides. Sci Transl Med 6:262ra157
Chen, Joseph C; Johnson, Brittni A; Erikson, David W et al. (2014) Seminal plasma induces global transcriptomic changes associated with cell migration, proliferation and viability in endometrial epithelial cells and stromal fibroblasts. Hum Reprod 29:1255-70
Usmani, Shariq M; Zirafi, Onofrio; Müller, Janis A et al. (2014) Direct visualization of HIV-enhancing endogenous amyloid fibrils in human semen. Nat Commun 5:3508
Shanmugasundaram, Uma; Critchfield, J William; Pannell, Jane et al. (2014) Phenotype and functionality of CD4+ and CD8+ T cells in the upper reproductive tract of healthy premenopausal women. Am J Reprod Immunol 71:95-108
Chen, Joseph C; Erikson, David W; Piltonen, Terhi T et al. (2013) Coculturing human endometrial epithelial cells and stromal fibroblasts alters cell-specific gene expression and cytokine production. Fertil Steril 100:1132-43
Chan, Jonathan K L; Greene, Warner C (2011) NF-ýýB/Rel: agonist and antagonist roles in HIV-1 latency. Curr Opin HIV AIDS 6:12-8
Shacklett, Barbara L; Ferre, April L (2011) Mucosal immunity in HIV controllers: the right place at the right time. Curr Opin HIV AIDS 6:202-7
Shacklett, Barbara L; Greenblatt, Ruth M (2011) Immune responses to HIV in the female reproductive tract, immunologic parallels with the gastrointestinal tract, and research implications. Am J Reprod Immunol 65:230-41

Showing the most recent 10 out of 16 publications