HIV infection is closely linked to the growth of the HIV virus in the body. Much of this information was obtained from studying how the HIV virus grows in circulating blood. Recent studies have shown that the lymphoid tissue (part of the immune system) is a major site where HIV is found in the body and is also where much of the HIV virus growth occurs. This study will examine not only blood but also lymphoid tissue to gain a better understanding of the disease and how to treat it.