HIV-infection and in vivo lipopolysaccharide-induced release of cytokines. An amplified mechanism of damage to the host.

Bacterial lipopolysaccharides (LPS) or endotoxins are potent triggers of the cytokine (CK) cascade. These CKs are immune mediators which produce many biological effects and could play a detrimental rather than beneficial role in the host. In this review emphasis will be placed on the participation of two CKs, tumor necrosis factor [TNF-alpha and interleukin (IL-1) beta], in the pathogenetic development of HIV infection. We have found that TNF and IL-1 circulate in exaggerated amounts in the blood of HIV-infected subjects from the earliest phases of infection. Furthermore, we have observed a strict correlation between plasma LPS and IL-1 beta levels, thus indicating that endotoxins could account for the production of CKs in the course of HIV infection. Finally, the demyelinating role of TNF-alpha either in experimental models or in the course of AIDS dementia complex is outlined.