Cryopreservation of mouse peritoneal macrophages

A method for the preservation of mouse peritoneal macrophages is described. Using 5% dimethylsulphoxide with either a cooling rate of 1 degree C/min or two-step cooling with 10 min interruption at -30 degrres C allows 80% survival as judged by pinocytic activity. An important finding was that the cells must be handled at 0 degrees C both before and after freezing.