At the start of the meeting, Tony Fauci, director of AIDS research at NIH, said that the path forward is becoming clear. Analyzing vaccines such as the Thai Trial will allow us to identify the “correlates of protection,” which will tell us how to make a vaccine that will get the job done. Just a few years ago, experts were focused on developing a vaccine that would stimulate cell-based immune responses to kill virally-infected cells – the strategy behind the failed Merck vaccine.
However, it was clear from many presentations at the meeting that the pendulum has swung to antibodies. Many new antibodies with potent HIV activity are being identified. The work of a number of labs finds that it takes about two years for such antibodies to be developed in HIV-infected individuals, and about 10-20% of HIV-infected individuals develop such antibodies.
That's the good news.
The bad news is that these antibodies are formed by changes that take place slowly over time, and so it will be difficult to develop a vaccine that will stimulate this type of antibody. However, the Thai Trial vaccine did not generate these special, HIV-neutralizing antibodies. Other studies reported at the meeting suggested that different types of antibodies, which lack neutralizing activity, also can provide protection from infection. It will be interesting to see if such antibodies played a role in the protection observed in the Thai Trial.
One of my favorite things about big conferences like the AIDS Vaccine 2010 meeting is getting to see the other Elizabeth Glaser Scientists. When the Foundation was first established, Elizabeth and her team decided the best way forward was to identify promising young researchers and support their work with grants to assist pediatric AIDS research. They chose very wisely; most of the Glaser Scientists are now the leaders in the field.
We know each other well – we talk about experiments and results, we inspire and challenge each other, and we tease and torment each other. It's like being part of a big, extended family of driven, ambitious, successful, and sometimes crazy brothers, sisters, aunts, uncles, and cousins. As a family, we comfortably pick each other's brains for new ideas and perspectives.
We now appear to have a way forward and need to get busy defining the potential correlates of protection identified in the Thai Trial. Next year we will meet again in Bangkok, Thailand, a fitting place to investigate the next generation of vaccine development.
Thomas Hope, Ph.D., is a professor of Cell and Molecular Biology at the Feinberg School of Medicine at Northwestern University. He received the Elizabeth Glaser Scientist Award in 2004 for his use of state-of-the-art imaging methodologies to determine the mechanism of maternal-fetal transmission of HIV. Learn more about the Elizabeth Glaser Scientist Award and see other award recipients here.