This article, OSU discovery may unlock AIDS cure, was published in my local newspaper (Corvallis Gazette-Times) on Friday. Researchers at Oregon State University (in Corvallis) have studied Mycobacterium avium, a common bacteria found in water and food. Most people are not affected by this bacteria, but people with compromised immune systems (e.g. AIDS patients) can be infected by it. When they are, it often kills them.
What makes this article relevant to us is that M. avium in its original state is incapable of infecting other cells. Over time, M. avium has evolved by acquiring DNA from other sources. This additional DNA codes for proteins that M. avium can release into potential host cells. As a result, the bacterium is incorporated into the host cell, rather than being phagocytosed (ingested) by it.
Potentially, blocking the proteins that allow the bacterium to be ingested may prevent infection of AIDS patients, and prolong the lives of AIDS patients who otherwise might be killed by M. avium.