[Morphologic and functional changes in thrombocytes after deep freezing with DMSO].

Background: During the past decade much work has been carried out towards 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 with DMSO.

Materials and methods: Single-donor platelet concentrates were cryopreserved in liquid nitrogen by use of DMSO. Before, during and after the freezing process samples were taken for analysis of ultrastructure and platelet function.

Results: While after isolation and addition of DMSO a normal ultrastructure of platelets could be observed, clear signs of beginning cell necrosis were detected after thawing and resuspension in autologous plasma. Fibrinogen-binding capacity and platelet aggregation were significantly diminished.

Conclusions: Although cryopreserved platelets are characterized by hemostatic effects in vivo, it seems conceivable that these effects could be improved by further development of platelet-freezing techniques.