Microbicide and vaccine both hit snags

PRO 2000, the microbicide gel, has failed to protect women against HIV infection in the largest microbicide study to date.

Meanwhile, scientists seeking to understand how to make an HIV vaccine have found the cause of a major roadblock. It turns out that the immune system can indeed produce cells with the potential to manufacture powerful HIVblocking antibodies, but at the same time, the immune system works equally hard to make sure these cells are eliminated before they have a chance to mature.