amfAR, The Foundation for AIDS Research

January 2007: New amfAR Research Grants Aim to Advance Understanding and Prevention of Rectal HIV Transmission

NEW YORK [January 18, 2007] — amfAR, The Foundation for AIDS Research, has awarded nearly $1 million for eight new research grants and fellowships aimed at increasing understanding and prevention of rectal HIV transmission, Dr. Rowena Johnston, amfAR’s vice president of research announced today.

“Twenty-five years after the first identification of AIDS, the taboos that surround an open discussion of sexual behavior are still haunting us in our efforts to contain this pandemic” said Dr. Johnston. “It is time for us to take an honest and unflinching look at how HIV is spread and how to minimize the risks. This new research should help us to further untangle this riddle.”

Sexual transmission accounts for the majority of HIV infections both in the United States and around the world, but how much of that transmission is due to anal intercourse remains unclear.

Although not often acknowledged, many heterosexual couples engage in anal intercourse and may not be aware that they are placing themselves at high risk for HIV and other sexually transmitted infections, Dr. Johnston said. In South Africa, a country with one of the highest rates of HIV infection in the world, little is known about the extent to which the virus is spread by anal intercourse. Dr. Joanne Mantell, a researcher at the Research Foundation for Mental Hygiene in New York, will use amfAR funding to gain insight into the frequency of anal intercourse in South Africa among heterosexuals and the circumstances under which it occurs.

Others, such as Drs. Charlene Dezutti of Magee-Women’s Research Institute and Foundation in Pittsburgh and Craig Hendrix of the Johns Hopkins School of Medicine in Baltimore, will strive to understand the interactions between the virus and the cells in the rectum and colon that can tip the scale towards the establishment of infection.

Understanding the extent to which anal intercourse spreads HIV infection will become increasingly important as researchers race to devise microbicides, which may be effective only when used vaginally. Findings made by these new amfAR researchers will contribute to the development of prevention technologies that can also be used by those engaging in anal intercourse.


The recipients of this $1 million (US) round of funding, and their projects are:

Alex Carballo-Dieguez, Ph.D.
Research Foundation for Mental Hygiene, Inc., New York, NY

Development of a standard rectal microbicide delivery device: Even if an effective rectal microbicide becomes available, people will not use it if it cannot be applied comfortably. Dr. Carballo-Dieguez plans to design a rectal microbicide delivery device that will ensure ease of use and comfort while appropriately delivering the microbicide. Incorrect delivery of such a product could negate its protective effects or even increase the risk of infection. Ultimately such a delivery device might be used in human trials of a rectal microbicide, to ensure that all products are tested in a standardized manner that allows comparison of the effectiveness of each of the microbicides.

Charlene Dezutti, Ph.D.
Magee-Womens Research Institute and Foundation, Pittsburgh, PA

Colorectal explants to study HIV transmission and microbicides: While details about HIV transmission in the female genital tract remain to be clarified, even less is known about such details in the rectum and colon. Dr. Dezzutti will study pieces of human colon and hemorrhoid tissue that will be exposed to HIV in a Petri dish. She will compare the differences in susceptibility to HIV infection of different regions of the colon, versus hemorrhoid tissue, and determine whether such differences are due to variability in the virus and/or in the cells first encountered by the virus. Such studies will allow researchers to develop ways of evaluating the effectiveness of rectal microbicides.

Craig Hendrix, M.D.
Johns Hopkins University School of Medicine, Baltimore, MD

Epithelial injury and HIV penetration after simulated ejaculation: The development of a rectal microbicide is even more complicated than a vaginal microbicide because the area to be protected from infection is so much larger and the tissues more delicate. Dr. Hendrix plans to explore which regions of the rectum and colon are most susceptible to HIV infection following intercourse, which will guide efforts in formulating a microbicide that will be most effective for rectal use. He also plans to delineate mechanisms whereby rectal and colon tissue are more prone to infection by HIV than the vagina, whether because of damage to the tissues due to intercourse itself or perhaps due to the chemical effects of semen.

Hongjie Liu, Ph.D.
Wayne State University, Detroit, MI

Mediation effects of network function on HIV risk behavior among Chinese MSM: Little is known about the extent to which men who have sex with men (MSM) also engage in sex with women. Dr. Liu plans to study this phenomenon among Chinese MSM, especially as regards their social networks. He will analyze the ways in which social networks, including sex partners, friends, and peers, as well as the Chinese collectivist culture, influence how many men engage in such behavior and how often it occurs. Ultimately Dr. Liu plans to develop an intervention to help reduce the rate at which Chinese MSM engage in unprotected sex with both men and women.

Joanne Mantell, Ph.D.
Research Foundation for Mental Hygiene, Inc., New York, NY

Anal sex practices in high-risk South African women and men: Very little is known about the extent to which anal intercourse contributes to the international HIV/AIDS epidemic, especially among heterosexuals. Dr. Mantell will study the prevalence of anal intercourse in South Africa, a country with one of the highest rates of infection in the world. After designing a culturally sensitive survey, she will describe how often anal intercourse takes place relative to vaginal intercourse, as well as attitudes that influence the likelihood of anal sex. Information about the frequency of condom use during anal versus vaginal intercourse will also help paint a picture of the spread of HIV in South Africa that will inform efforts to develop a rectal microbicide.

Roberto Speck, M.D.
University Hospital of Zurich, Zurich, Switzerland

Rectal transmission of HIV-1 in a novel mouse model: One of the limitations of HIV/AIDS research is the lack of a suitable animal model to conveniently study many of the biological phenomena associated with the disease. Dr. Speck has designed genetically engineered mice with an immune system that mimics that of humans, allowing him to study rectal transmission of HIV. He also plans to use the animals to discern whether virus-infected cells or virus particles alone are better suited for sexual HIV transmission, which cells are first infected and how, and whether damage to the rectum or colon is necessary for infection to occur.


Carolina Herrera, Ph.D./Mentor: Robin Shattock, Ph.D.
St. George’s University of London, London, United Kingdom

Colorectal responses to HIV-1 and modulation by microbicides: The cellular events leading to disseminated HIV infection following anal intercourse have never been fully elucidated. Dr. Herrera will study pieces of human rectal and colon tissue in a Petri dish to characterize the responses of those tissues after exposure to HIV or semen. In particular, she will look for indications of changes in the function of immune cells, and determine whether such changes always occur or only when HIV infection is established. In addition, she will compare those changes to responses induced by microbicides, which will ultimately help guide the design of a rectal microbicide.

Marjan Javanbakht, Ph.D./Mentor: Peter Anton, Ph.D.
University of California, Los Angeles, Los Angeles, CA

Anal intercourse, STIs, and HIV among STD clinic clients: The extent to which anal intercourse contributes to the spread of HIV between men who have sex with men, as well as heterosexuals, is not well understood. Dr. Javanbakht will analyze data collected from male clients attending a public STD clinic in Los Angeles, specifically those who have sex with both men and women. Behavioral and biological data will be pooled to form an overview of sexual behaviors that place clients and their partners at risk for HIV infection. The information she gleans will help predict what level of impact a rectal microbicide might have on slowing the spread of HIV/AIDS.

About amfAR

amfAR, The Foundation for AIDS Research, is one of the world’s leading nonprofit organizations dedicated to the support of AIDS research, HIV prevention, treatment education, and the advocacy of sound AIDS-related public policy. Since it’s founding in 1985, amfAR has been associated with important HIV/AIDS research. It has invested nearly $250 million in its programs and has awarded grants to more than 2,000 research teams worldwide since 1985.