Oct 29 2012
RUB-medical researchers want to trick the immune system
2.3 million Dollar funding from the Bill & Melinda Gates Foundation
To support their research for a vaccine against the HI-Virus, Prof. Dr. Klaus Überla of the Faculty for Medicine at the Ruhr-Universität Bochum and his research team will receive $2.3 million in funding within the next three years from the Bill & Melinda Gates Foundation. The scientists are part of the Collaboration for AIDS Vaccine Discovery (CAVD), which seeks to speed up the development of an HIV-vaccine through a rigorous exchange of information, methods and reagents. "The project rests upon our observation that certain immunological reactions seem to increase the risk of HIV-infection," Prof. Überla said. "We want to avoid these kinds of harmful immune system responses while still creating protective antibodies."
Earlier study: HIV-vaccine increases risk of infection
Prior attempts to develop vaccines against HIV have not been successful. The preparation that was used in the Merck Pharmacy's so-called STEP study actually increases HIV susceptibility. "It is extraordinarily important to understand why the vaccine has this effect," Überla said. "These findings could have an enormous impact on the development of future substances." By building on the findings of the STEP study, the research team plans to develop a new vaccine that will undergo in vivo testing.
T helper cells: HIV-proliferation vs. antibody production
Earlier studies have shown that certain antibodies against the envelope proteins of HIV could protect from HIV infection. Important for such antibody production are the CD4 T helper cells. Different kinds of these T helper cells recognize different pathogens in the body and signal other cells to create the appropriate antibodies in response to the invasive microorganisms. However, reactive CD4 T helper cells are also where HIV multiples particularly quickly. Therefore, if the number of HIV-responsive CD4 T helper cells increases as a result of the vaccine, the effect is simultaneously helpful and hurtful.
Helping, not hurting
The aim of the research project "Induction of affinity-matured HIV Env antibodies in the absence of HIV-specific T helper cells" is to investigate a new immunization method. Scientists associated with the project want to produce HIV antibodies through the use of T helper cells whose purpose is the recognition of other pathogens, rather than those which recognize the presence of HIV. This would mean that the number of T helper cells which respond to HIV would not go up through vaccination, thereby making it more difficult for HIV to multiply. The effectiveness of this new immunization method will be determined in cooperation with Dr. Stahl-Henning of the German Primate Center in Göttingen.