[Effect of repeated leukaphereses on the lymphocytogram of blood donors].

Donors risk lymphopenia as a result of thrombocytapheresis as well as leukapheresis. The importance of the removal of lymphocytes is speculative at present. In the study presented, 10 healthy blood donors underwent 5 consecutive, discontinuous flow-leukapheresis procedures in weekly intervals with the effect of a total loss of 2.6 X 10(10) lymphocytes. The number of peripheral lymphocytes decreased steadily from 1,850 +/- 417/microliter to 1,451 +/- 411/microliter over the 5-week period. A significant decrease comprised also OKT3+-, OKT4+- and B-lymphocytes but not OKT8+-cells. Accordingly the OKT4/OKT8 ratio was reduced though not significantly from 1.41 +/- 0.25 to 1.32 +/- 0.27. 6 months after the last apheresis, the total lymphocyte count, OKT3+- and B-lymphocytes were still significantly low. The long-lasting peripheral lymphopenia in cytapheresis donors has to be taken into account as one of the criteria for donor selection. Donors with less than 1,000 lymphocytes/microliter of peripheral blood should be excluded from cytapheresis procedures.