Dendritic cells are a type of white blood cell used by the body to fight infection. They are instrumental in presenting antigens (such as HIV antigens) to the body's immune system. Since dendritic cells are not functioning maximally in HIV-infected patients, infusion of dendritic cells from an HIV-negative sibling may enable the affected sibling's immune system to recognize foreign particles more readily and increase immune response against the virus.

Dendritic cells from an HIV-negative sibling are obtained and treated with various viral proteins (HIV vaccines) or immunomodulators. The treated dendritic cells are infused into the HIV-infected patient monthly for 6 months. Siblings must be able to donate on multiple occasions, and patients are followed every 2-4 weeks during the study. Patients are screened over 3 months prior to study entry.