Effect of Frozen-Dried Plasma and Frozen-Dried Embryo Juice on Tissue Cultures

Abstract

In view of the remarkable results obtained in keeping bacterial antigens, sera and other products without alteration for long periods of time, following freezing and drying in vacuo, it was undertaken to determine whether plasma and embryo juice for tissue culture could also be treated similarly. The following report describes briefly the procedure and the results obtained.

Young chickens were deprived of food for 24 hours and then bled aseptically by cardiac puncture. Not more than 20 cc of blood was removed at a time. It was prevented from clotting by being drawn into syringes moistened with a solution of heparin. The plasma was collected after centrifuging the blood on ice, and was pooled before distribution in one cc quantities in small glass ampoules prior to freezing and drying with a Lyophile∗ apparatus. The ampoules sealed in vacuo were labeled and stored in an icebox.

Twenty percent embryo juice was prepared in the usual manner,† using Ringer-Tyrode solution (glucose 0.2%) and chick embryos of 11 days' incubation. This material in one cc quantities was likewise frozen, dried, sealed in vacuo and stored. To determine whether these 2 products would serve as adequate media for tissue cultures, the following experiment was performed.

The ampoules of dried plasma and embryo juice which had been kept in storage for 3 months were filed, sterilized in alcohol, and wrapped in sterile gauze before breaking the necks to open them. The dried powders were dissolved and diluted to original volume with sterile, triply distilled water. The plasma always dissolved without residue but a few flecks of insoluble material remained in the embryo juice. Cultures of 11-day chick embryo hearts were planted in equal parts of the experimental plasma and embryo juice.