A T Cell-based HIV Vaccine

The purpose of this research study is to develop a vaccine against Human immunodeficiency
virus (HIV), a disease that causes AIDS in people,. The investigator will be looking at
viruses similar to HIV in animals. Since these viruses are very similar to HIV, the blood
from humans who have been exposed to HIV will be tested to see if the immune system will
recognize the HIV and prevent infection.

HIV targets the immune system by attacking certain T cells called CD4+ T cells. There are
parts on the AIDS viruses that help the virus infect these cells and other parts that help
the immune system prevent viral infection by activating protective T-cells that fight HIV.
Different T-cell populations are very important in most vaccines as they act as "effectors"
that work as part of the immune system to recognize and fight off HIV infection. When
effector T cells are activated by appropriate "protective" part(s) of the virus they either
block HIV from reproducing or kill HIV infected cells. By finding these common protective
parts of each of these human and animal AIDS viruses, the investigator hopes to make a
vaccine that helps the immune system prevent HIV infection by avoiding parts that attack CD4+
T cells and may worsen HIV infection and selecting for parts that stimulate effector T cells
that fight HIV infection.