In vitro reactivity to concanavalin A of bovine lymphocytes after cryopreservation

Abstract

Cryopreservation of bovine peripheral lymphocytes and its effect on the in vitro response to concanavalin A tested in a microculture system is described. Using DMSO as cryoprotectant in the medium, the cells were cooled to −30°C at 1.3°C/minute and further to −80°C at 6°C/minute and then rapidly to −196°C by dropping in liquid nitrogen. The cells were recovered by rapid thawing in water at 30–35°C and washed twice before use in the stimulation test. Ten percent DMSO had a much better protective effect than 5%; addition of 25% fetal bovine serum to the freezing had no favourable effect. In most of the 16 animals used in the experiments the frozen lymphocytes gave the same or a higher response to Con A than those kept in the DMSO containing medium at 4°C for two hours.

The responses of the frozen cells were comparable to those of fresh lymphocytes (kept at 4°C for two hours in medium without DMSO).