Effects of Interferon-α on a Reduced Release of Interleukin-8 from Latently HIV-1-Infected Monocytic Cell Line U937 Cells

The effects of human interferon-α (IFN-α) on the release of an antimicrobial interleukin, interleukin-8 (IL-8), from human immunodeficiency virus type 1 (HIV-1)-infected myelomonocytic cell line, U937, were studied in vitro to evaluate the potential of IFN-α in the management of acquired immunodeficiency syndrome (AIDS)-associated opportunistic diseases. The latently HIV-1-infected U937 cells (U937/HIV-1(L)) showed a marked reduction of IL-8 secretion as compared to uninfected U937 cells, whereas IL-8 release from productively HIV-1-infected U937 cells was comparable to uninfected cells. The IFN-α recovered partially the reduced IL-8 level from U937/HIV-1(L) cells in a dose-dependent manner. Any significant inhibition of IFN-α-augmented IL-8 secretion by anti-IL-1 antibody was not observed, suggesting that the enhanced IL-8 secretion occurred without augmenting IL-1 production. The IFN-α-augmented IL-8 secretion from latently HIV-1-infected U937 cells may suggest a beneficial potential of IFN-α in a treatment of bacterial or fungal infection frequently seen in patients with progressive stages of HIV-1 infection.