Cryopreservation of newly formed human and mouse hybridoma cells

The aim of this study was to develop an optimal technique for cryopreservation of newly formed human and mouse hybridoma cells immediately after fusion. It was shown that human hybridoma cells could be frozen most successfully at a cooling rate of 5 K/min whereas mouse hybridomas at 1 K/min. The percentage of FCS in cryopreservation media (30 or 90%) had no influence on the recovery of both types of hybridomas. For testing the efficiency of freezing, the fusion rate (number of growing and Ig producing hybridomas), the ratio of IgM:IgG-producing initial hybridoma lines and yields of specific wells were analysed. Comparable results were registered when optimally cryopreserved and non-frozen material was studied. Optimization of the cryopreservation of newly formed hybridomas may be of methodological importance, especially when a time-consuming screening for antigenic specificities must be carried out.