Development of Low Immunogenic Antifreeze Peptides for Cryopreservation

Thesuccessful application of antifreeze proteins (AFPs) for biospecimencryopreservation is limited by their immunogenicity. In this work,three low immunogenic antifreeze peptides are developed based on thefunctional motif of the Tenebrio molitor antifreezeprotein (TmAFP). In vivo tests demonstrate theirnegligible cytotoxicity to hepatic function, myocardial enzymes, andrenal function. Meanwhile, molecular dynamics simulations demonstratethat the -OH groups of residues Thr1 and Thr3 perfectly matchthe lattice of the ice crystal by H-bond interaction, thus resultingin the adsorption of peptides onto the ice-crystal surface. Accordingly,the peptides exhibit activities on ice-recrystallization inhibition(IRI), thermal-hysteresis (TH), and ice-crystal shaping. Furthermore,these peptides can also protect cell membranes. During the cryopreservationof NIH/3T3 cells, the addition of only 0.5% peptides can significantlyimprove cell survival rates (from 37.86% to 81.32%). This work providesnew insights to develop biocompatible agents for cryopreservation.