NTPDase activity in human lymphocytes is not affected by therapeutic doses of anti-HIV drugs

Abstract

NTPDase (EC 3.6.1.5) is an enzyme that hydrolyzes extracellular nucleoside tri- and/or diphoshates forming AMP that can serve as a substrate for an ecto-5′-nucleotidase (EC 3.1.3.5) with liberation of adenosine, a modulator of vascular tone and inhibitor of platelet aggregation. These enzymes also occur in lymphocytes playing an important role in immune function. In this study, it was investigated if anti-HIV therapy could affect NTPDase activity in human lymphocytes. Samples of lymphocytes were incubated with different concentrations of anti-HIV drugs and NTPDase activity was determined by colorimetric assay with quantification of inorganic phosphate released. There is not significant difference of NTPDase activity among samples with therapeutic doses of anti-HIV drugs tested when compared with controls. NTPDase activity in peripheral human lymphocytes is not altered by anti-HIV therapy.