On the Biocompatibility of IBM 2997 Continuous Flow Plateletapheresis

Abstract

Summary:During the procedure of centrifugation cytapheresis donors occasionally experience adverse clincial reactions. We evaluated the possibility of whether activation of granulocytes and their subsequent release reactions, which may have been triggered by this extracorporeal circuit, were responsible for these adverse effects. Six blood samples were obtained during various set intervals during plateletapheresis. Of these, four samples were taken directly from each donor. The remaining two were drawn from the efferent lines, i.e. those which return blood from the cytapheresis machine back to the donor. Reactive oxygen species produced by granulocytes were monitored by chemiluminescence using microamounts of whole blood or isolated granulocytes. Furthermore, secreted granulocyte products such as neutral proteinase elastase, present in plasma in a complex with oti-proteinase inhibitor (complexed elastase), and lysosomal -glucuronidase were examined. A complete blood cell count, as well as values of haemoglobin, haematocrit, lactate dehydrogenase, protein, albumin and proteinase inhibitors such as oc 2 -macroglobulin and αϊ-proteinase inhibitor were also determined. Complexed elastase increased from a preapheresis value of about 140 μg/l to about 180 μg/l at the end of the cytapheresis. All other clinical chemical and cytological values were 8 to 12 percent lower than preapheresis values, which can be attributed to inherent plasma volume expansion. Reduced chemiluminescence was observed upon stimulation of phagocytes in the whole blood assay (about 700 counts/min χ ΙΟ 3 χ 50000 cells vs. about 600 counts/min χ ΙΟ 3 χ 50000 cells). This decrease was also seen with stimulated granulocytes (about 5800 counts/min χ ΙΟ 3 χ 50000 cells vs. about 4500 counts/min χ ΙΟ 3 χ 50000 cells). Unstimulated granulocytes, on the other hand, showed an increased native chemiluminescence. These data do not, however, indicate a cytapheresis mediated activation of the oxidative metabolism of granulocytes. Concomitant discharge of proteolytic enzymes remains, therefore, of no clinical importance.