Use of sorbitol in the cryopreservation of babesia.

Blood collected from mice infected with Babesia microti was frozen at two different rates to -196 degrees C using 19 per cent (w/v) glycerol as cryoprotectant. Survival of the parasites was measured by recording the parasitaemias of mice inoculated with thawed blood. Parasite survival was increased by using a solution of sorbitol in saline rather than Hanks' balanced salt solution as the diluent for the glycerol and for washing the recovered blood.