HEXADECYLPHOSPHOCHOLINE INDUCES INTERFERON-GAMMA SECRETION AND EXPRESSION OF GM-CSF MESSENGER-RNA IN HUMAN MONONUCLEAR-CELLS

The effects of hexadecylphosphocholine (HePC) on secretion of interferon-γ (IFN-γ) and steadystate levels of IFN-γ and GM-CSF mRNA were studied in human mononuclear cells. Cells from healthy donors were stimulated with either interleukin 2 (IL-2) alone, IL-2 plus phytohemagglutinin (PHA), or IL-2 plus HePC. In IL-2-treated cultures, the concentration of IFN-γ was low, IFN-γ and GM-CSF transcripts were not detectable by Northern blot analysis. In contrast, IL-2 plus HePC strongly increased the expression of the IFN-γ and the GM-CSF genes and the secretion of IFN-γ in most analyzed cultures. A similar effect could be detected with IL-2 plus PHA. The HePC-mediated enhancement of cytokine expression appeared later than the PHA-induced stimulation. These data indicate that HePC is able to enhance the immune response of IL-2-stimulated mononuclear cells resulting in GM-CSF and IFN-γ gene expression and IFN-γ secretion. © 1992.