a cytokine, produced by activated monocytes and macrophages, that can destroy tumors. When
chronically elevated (as may occur in HIV disease), TNF-alpha may lead to fever, anorexia, hypermetabolism and wasting. TNF-alpha may block the production of enzymes that digest fats, leading to the breakdown of muscle tissue. In laboratory tests TNF-alpha has been shown to stimulate HIV replication. Some drugs (e.g., thalidomide, ketotifen) reduce TNF-alpha levels. TNF-beta is released by CD4 and CD8 T-cells when stimulated by an antigen. VERIFY TNF-BETA.