In vitro infection of macrophages by HIV: correlation with cellular activation, synthesis of tumour necrosis factor alpha and proteolytic activity.

Macrophages were obtained after differentiation of healthy donor monocytes. Seven to 9 days after isolation, cells were infected with HIV1. Tumour necrosis factor alpha (TNF alpha) biological activity, TNF alpha- and 1-6-fructose-diphosphatase-gene expression and gelatinase activity were sequentially determined and correlated with viral infection and replication. TNF alpha was only detectable when mature viral particles were isolated in cell culture supernatants; 1-6-fructose diphosphatase mRNA was hyperexpressed in infected cells and its proteolytic activity was tremendously decreased during the early days postinfection. These results would seem to indicate that in human macrophage activation, cytokine secretion and microbicidal proteolytic activity are strongly modified by HIV infection.