Function and morphology of platelets produced for transfusion by intermittent-flow centrifugation plateletpheresis or combined platelet-leukapheresis.

The effects on platelet function of intermittent-flow centrifugation pheresis were measured employing platelets collected from ten donors by combined platelet-leukapheresis with hydroxyethyl starch (LP) and from ten by plateletpheresis (PP) by similar techniques except without starch. Greater numbers of platelets were produced by LP than by PP. Aggregation of platelets collected by both LP and PP was normal (did not differ from prepheresis baseline) to collagen and to 10(-5)M adenosine diphosphate (ADP). Slight impairment to aggregation with 2 X 10(-6)M ADP and 5.5 X 10(-5)M epinephrine occurred with both techniques. These abnormalities, however, were significantly less severe in platelets collected by LP. Platelet morphology by electron microscopy was nearly normal, although glycogen granules were absent in LP platelets. Thus, hydroxyethyl starch, at doses currently used during a single LP, does not enhance abnormalities of platelet aggregation over those expected to result from PP alone. Actually, LP platelets function better in vitro than those collected by PP. Large numbers of platelets can be harvested by LP, and their use as a component that is comparable to PP platelets may mean improved efficiency and reduced costs for pheresis centers.

Platelet function in donors undergoing intermittent-flow centrifugation plateletpheresis or leukapheresis.

Platelet dysfunction and prolonged bleeding have been seen in man when glucose polymer solutions, such as dextran, are used to volume replacement. Hydroxyethyl starch (HES) is a glucose polymer slightly different from dextran, which is used as a sedimenting agent in leukapheresis procedures. This controlled study was performed to evaluate the effect of HES on platelet function in centrifugation leukapheresis donors. Plateletpheresis using the same machines and techniques but without HES was the control. Platelet function was assessed by bleeding time, platelet count, adhesiveness to glass beads and aggregation to collagen, epinephrine and several concentrations of ADP, before and after the pheresis procedures. Except for a decrease in platelet count after both procedures, no other major changes in platelet function were seen. After one exposure in previously unpheresed donors, HES does not induce platelet dysfunction.

Gram-negative sepsis treated with neutrophils collected exclusively by intermittent flow centrifugation leukapheresis.

The effectiveness of neutrophils prepared for transfusion by intermittent flow centrifugation leukapheresis (IFCL) as treatment for serious bacterial infections in neutropenic patients has not been documented in the literature. Their value, in fact, has been questioned. We report that IFCL neutrophils are similar to cells prepared by other techniques in the ability to support neutropenic patients with culture-proven, gram-negative sepsis unresponsive to antibiotics.

Combined platelet-leukapheresis: a technique for preparing separate platelet and granulocyte-platelet units from single donors.

One donor can provide separate platelet and granulocyte-platelet units that have the potential to fulfill the needs of two recipients. Combined platelet and leukapheresis were performed in the presence of hyddroxyethyl starch and citrate employing the Haemonetics Model 30 Blood Separator. Platelets and granulocytes were separated subsequently by centrifugation and two individual units were prepared for transfusion. The platelet units contained a mean of 4.4 x 10(11) platelets/unit and were nearly devoid of leukocytes. The combined granulocyte-platelet units contained a mean of 7.38 x 10(9) neutrophils/unit and 3.06 x 10(11) platelets/unit. Thus two separate units containing sufficient numbers of cells for transfusion can be obtained from pheresis of one donor.