The effect of immunomodulators on PHA or γ-IFN induced release of neopterin from purified macrophages and peripheral blood mononuclear cells

Immunomodulators cause changes in neopterin- release from purified macrophages or peripheral blood mononuclear cells by affecting the macrophage and T cell subsets activity, the intracellular cGMP/cAMP balance, or the intracellular pteridines-related biochemical pathways. Increased neopterin release was achieved by γ-IFN or its inducers (PHA, IL-2), by interfering with the biopterin production by increased levels of cGMP or by decreasing the activity of the T suppressor cells. The released neopterin levels decreased due to decreased macrophage and T-helper cell activity or due to increased levels of cAMP. The in vitro effect of the immunomodulators has to be taken into account when assessing the neopterin levels in immunomodulators-treated patients.