THE USE OF ANTIFREEZE GLYCOPROTEINS IN TH E FREEZING OF EARLY MOUSE EMBRYOS IN LIQUID-NITROGEN

The cryoprotective properties of antifreeze glycoproteins (AFGPs) isol ated from White Sea cod (Gadus morhua) blood were analyzed. Improved p reservation of morphological characteristics was observed in two-cell mouse embryos frozen in the presence of AFGP but without other cryopro tectors. However, subsequent development after thawing was achieved on ly with embryos frozen in a medium containing both AFGP and dimethyl s ulfoxide. The maximum increase in the number of surviving embryos (by a factor of approximately two, as compared with the control) was obser ved at AFGP and DMSO concentrations of 20 mg/ml and 25%, respectively.