IL-6 and TNF-alpha are produced naturally by the body. High levels of TNF-alpha lead to increased IL-6 production and increased HIV replication, therefore helping the virus infect the body. HIV-positive patients who receive IL-2 (interleukin-2, a protein that helps the immune system fight infection) tend to have higher levels of IL-6 and TNF-alpha than patients not receiving IL-2. These increased levels may contribute to some of the flu-like symptoms related to IL-2 administration. TNFR:Fc can neutralize TNF-alpha to decrease the action of TNF-alpha and, in turn, decrease the amount of IL-6 in the body. TNFR:Fc may, therefore, have a role in the treatment of HIV disease or in relieving some of the symptoms related to IL-2 administration.