CHANGES IN MORPHOLOGY AND FUNCTION OF PLA TELETS AFTER CRYOPRESERVATION WITH DMSO

Background: During the past decade much work has been carried out towa rds establishing the optimum method for cryopreservation of platelets. Among the various cryoprotectants dimethyl sulfoxide (DMSO) has been shown to be the most effective. This report describes ultrastructural and functional changes of platelets during the deep-freezing process w ith DMSO. Materials and Methods: Single-donor platelet concentrates we re cryopreserved in liquid nitrogen by use of DMSO. Before, during and after the freezing process samples were taken for analysis of ultrast ructure and platelet function. Results: While after isolation and addi tion of DMSO a normal ultrastructure of platelets could be observed, c lear signs of beginning cell necrosis were detected after thawing and resuspension in autologous plasma. Fibrinogen-binding capacity and pla telet aggregation were significantly diminished. Conclusions: Although cryopreserved platelets are characterized by hemostatic effects in vi vo, it seems conceivable that these effects could be improved by furth er development of platelet-freezing techniques.