Scientific American has an interesting note about breakthrough HIV research being conducted at Harvard Medical School, where Bing Chen and his colleagues have been able to get the first sharp pictures of the gp120 protein, which enables HIV to fool the immune system effort to destroy it, while continuing to infect host cells. 

gp120 is a highly variable protective membrane that allows HIV to evade the attack and survive in the body long term. The research undertaken at Harvard studies how the molecule changes shape once it recognizes and binds to the cell. This is yet another important milestone in understanding how HIV infects a cell and how to stop that from happening.