Human platelets frozen with glycerol in liquid nitrogen: biological and clinical aspects

Abstract
Platelets were frozen using glycerol as a cryoprotective agent, a rapid cooling rate and liquid N for storage. The cryopreserved platelets were thawed at 42.degree. C and infused without washing. The quality of the thawed platelets is equivalent to platelets stored for 24 to 48 h at room temperature. The availability of HLA phenotyped leukocyte poor platelets can reduce the frequency of sensitization to strong antigens and provide clinically effective platelets for alloimmunized patients. Clinical observations of 70 patients with thrombocytopenia and bleeding transfused with cryopreserved platelets are reported.