IL-27 inhibits HIV infection in macrophages. (A) Monocyte-derived macrophages were infected with 10³ TCID₅₀/mL BaL for 2 hours. Cells were washed, 10% DMEM added, and IL-27 at 0, 1, 10, and 100 ng/mL added only once after infection. Cells were fed every 3 to 4 days with 10% DMEM. Virus replication was measured by p24 ELISA at day 10 postinfection (n = 3). (B) Macrophages were infected with HIV for 2 hours, washed, 10% DMEM added, and IL-27 at 100 ng/mL added only once after the 2-hour infection period. Supernatant aliquots were obtained every 3 to 4 days and HIV measured by p24 ELISA (n = 3). (C) Macrophages (n = 3) were treated overnight with IL-27 (100 ng/mL) and the cells analyzed by flow cytometry after staining with antibodies specific for CD4, CXCR4, and CCR5. (D) In parallel to IL-27, IL-12 and IL-23 were added once at 100 ng/mL after HIV_BaL was washed out. Cells were fed every 3 to 4 days with 10% DMEM, and virus replication measured in day 10 supernatants by p24 ELISA (*P < .02; n = 3, representative data shown).