Investigation of the effect of long-term whole blood donation on immunologic parameters

Few studies addressing possible immune sequelae of long-term whole blood donation have been published. The purpose of this study was to determine if there were any differences in lymphocyte subsets, monocyte and neutrophil receptors, and antigens important to host defense in committed whole blood donors and in nondonor controls. Blood samples were obtained from 27 whole blood donors who had been donating on a regular basis for at least 4 years and from 21 nondonor controls. A panel of single- and dual-labeled monoclonal antibodies was used to characterize peripheral white cells, and then the cells were analyzed by flow cytometry. Lymphocyte subsets included T (CD3) cells, helper T (CD4) cells, suppressor T (CD8) cells, B (CD19) cells, natural killer (NK) (CD56) cells, and subpopulations of T cells defined by the coexpression of markers for CD3/HLA-DR, CD3/CD56, and CD8/CD11b. Monocyte and neutrophil analysis included quantitation of receptors for C5a, formyl-met-leu-phe, and C3bi (CR3). Monocytes were also analyzed for expression of HLA-DR and CD14 antigens. No significant differences were observed in the whole blood donors and nondonor controls for any of these factors used to assess immunologic status, except for an increase in C3bi receptors on both neutrophils and monocytes from whole blood donors. These findings indicate that the lymphocyte parameters analyzed in this study are unaltered by long-term whole blood donation. Further research is necessary to determine the significance of complement receptor upregulation in whole blood donors and to identify any changes in the functional characteristics of peripheral white cells from whole blood donors.