Synthesis and interferon-gamma controlled release of pteridines during activation of human peripheral blood mononuclear cells.

Lectin stimulation of human peripheral blood mononuclear cells causes an increase in neopterin, biopterin, 6-hydroxymethylpterin and 6-formylpterin, as was determined by HPLC after iodine oxidation of the acid extract. After 72 h, pteridines peak at levels 5-10 fold as compared to resting cells. Levels decline to initial values during the following 24 h. Changes in pteridine proportions indicate that the synthesis of tetrahydrobiopterin proceeding from dihydroneopterin triphosphate is controlled during the process of lymphocyte activation. The release of both cellular neopterin and biopterin, but not of 6-hydroxymethylpterin and its aldehyde, is controlled by interferon-gamma.