We tried to analyze the status of 10 units of frozen thawed apheresis platelet concentration by 6% DMSO method for the evaluation of practical applicability.
The platelet concentrations were transferred to PL-732 (Baxter, USA) cryopreservation bag, and DMSO is added to those bag at slow rate until expected final 6% concentration is achieved, thereafter those were directly placed to -80℃ refrigerator
for
freezing. Someday later from 1 week to 1 month, those were thawed at 37℃ water bath, and then washed by same volume of ABO matched plasma.
In the course of cryopreservation, about 7% of platelets were lost and the mean recovery rate of platelet was 93% compared with those of unfrozen status. LDH, the values of platelet lysis, and pH were within normal limits, whereas platelet
aggregation
test shows decreased aggregation to collagen and ristocetine compared with those of unfrozen status (p<0.05) but they were clinically acceptable.
We suggest that the frozen platelets may be useful in a some clinical situation such as hematologic malignancy and solid tumor by autologous transfusion.
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