Cytokine regulation of the myeloid glycoprotein CD14

Monocyte membrane CD14 (mCD14) antigen expression was measured in normal human monocytes and blood monocyte-derived macrophages. Seven-day culture of monocytes in serum-containing medium lead to an increase in mCD14. Addition of interferon-gamma (IFN gamma) or interleukin-4 (IL-4) to monocytes caused a dose-dependent reduction in mCD14 within 3 or 45 h respectively. These effects were strong in monocytes, weak in macrophages, and they were blocked by anti-IFN gamma and anti-IL-4 antibodies, respectively. Interleukin-2 and interferon-alpha produced a decrease in mCD14 in mononuclear leukocyte cultures but not in purified monocytes. Their effect was abolished in the presence of anti-IFN gamma. Other cytokines (TFN alpha, Ill beta, IL-6, IL-3, IL-5, GM-CSF, TGF beta 1) did not change mCD14. In conclusion, IFN gamma and IL-4 are revealed to be the only cytokines which directly affect monocyte CD14 expression.