Interleukin-2 inhibits HIV-1 replication in human macrophages by modulating expression of CD4 and CC-chemokine receptor-5

Abstract

Objective: To determine the effect of recombinant human interleukin (IL)-2 on HIV-1 replication and macrophage colony stimulating factor (M-CSF) production by HIV-1-infected monocyte-derived macrophages (MDM).

Design: Therapeutic use of IL-2 increases the number and function of CD4+ T cells. IL-2 also increases M-CSF production and M-CSF receptor expression by human monocytes, but the subsequent effects on HIV-1 replication in MDM have yet to be determined. MDM from HIV-1-seronegative donors were cultured in the presence and absence of IL-2 and infected with HIV-1. Harvested supernatants were monitored for reverse transcriptase activity and M-CSF production.

Results: Reverse transcriptase activity was significantly lower when MDM cultures were treated with IL-2 for 10 days prior to infection with HIV-1. IL-2 did not stimulate production of inhibitory chemokines or cytokines, but FACS analysis revealed that expression of CD4, the primary HIV-1 receptor, and CC-chemokine receptor-5, a coreceptor used by macrophage-tropic viruses, are down modulated after treatment with IL-2.

Conclusion: IL-2 may not only be of benefit in restoring immune function in AIDS patients, but may also help to prevent the infection of healthy macrophages by decreasing their expression of HIV-1 receptors.