To determine whether non-productive infection of monocytes occur, we analyzed gag and tat mRNA, and gp120 expression in freshly elutriated and HIV-exposed monocytes cultured 2 to 48 hours in media with and without human recombinant macrophage colony stimulating factor (MCSF, induce monocyte differentiation to macrophage). The gene discussed is ITIH4; the disease is infection.