[Adenosine deaminase activity in T-enriched and T-depleted preparations of human peripheral lymphocytes]

Adenosine deaminase activity has been determined in T-enriched and T-depleted preparations of peripheral mononuclear cells from 6 normal subjects. T-enriched populations showed ADA levels lower than unseparated mononuclear cells (1.84 +/- 0.30 vs. 2.36 +/- 0.59 nmol NH3/min/10(6) cells). The highest values were found in T-depleted populations (2.46 +/- 0.39). Considering T cells percentages in our mononuclear cell preparations, T cells account for 64% of the biochemical ADA activity of peripheral blood mononuclear cells and the remaining 36% is due to non-T cells. The method for cell separation and enzymatic activity determination we used could be highly suitable for monitoring ADA levels in pathological conditions.