LEUKOCYTE FILTRATION DOES NOT AFFECT LYMPHOCYTE SUBPOPULATIONS AND NKCELL-FUNCTION IN RECIPIENTS OF BLOOD-TRANSFUSIONS

Background and objectives: The possible immunosuppressive action of bl ood transfusion has aroused great interest recently, particularly with respect to its effects on tumor growth and recurrence rate of maligna nt disease. Materials and methods: The effect of blood transfusion on lymphocyte subpopulations and NK cell function preoperatively and 6 mo nths postoperatively was studied in 129 patients treated with elective surgery for colorectal malignancy. Forty-two patients (33%) received blood transfusions, 21 of them randomly allocated to receive leukocyte -depleted blood products. Investigation was by means of conventional l aboratory methods. Results: In 21 patients receiving a median of 3 uni ts of non-leukocyte-depleted blood products (NLD), a significant reduc tion in CD4+ lymphocytes (44% vs. 40%, p<0.01) occurred. In contrast, no significant changes in CD4+ lymphocytes were observed in the 21 pat ients transfused with leukocyte-depleted blood products (LD). However, with respect to lymphocyte subpopulations and NK cell function, diffe rences between the NLD and LD groups were not significant. There was a marginal decrease in HLA-DR+ lymphocytes in the NLD patients without a history of previous transfusion. Conclusions: There seems to be no m ajor change in lymphocyte subpopulations and NK cell function 6 months after blood transfusion. Thus we cannot confirm our previous findings of a reduced number of CD20+ cells after blood transfusion.