Isochoric supercooling at -3°C enabled 50-65% of human cardiac microtissues to resume normal spontaneous beating activity after 24 to 72 hours of preservation without chemical cryoprotectants.
Isochoric supercooling enables the successful sub-zero preservation and revival of functional 3D human cardiac microtissues for up to 72 hours without chemical cryoprotectants.
Low-temperature biopreservation and 3D tissue engineering present two differing routes towards eventual on-demand access to transplantable biologics, but recent advances in both fields present critical new opportunities for crossover between them. In this work, we demonstrate sub-zero centigrade preservation and revival of autonomously beating three-dimensional human induced pluripotent stem cell (hiPSC)-derived cardiac microtissues via isochoric supercooling, without the use of chemical cryoprotectants. We show that these tissues can cease autonomous beating during preservation and resume it after warming, that the supercooling process does not affect sarcomere structural integrity, and that the tissues maintain responsiveness to drug exposure following revival. Our work suggests both that functional three dimensional (3D) engineered tissues may provide an excellent high-content, low-risk testbed to study complex tissue biopreservation in a genetically human context, and that isochoric supercooling may provide a robust method for preserving and reviving engineered tissues themselves.
Powell‐Palm et al. (2021) studied Cardiac microtissue preservation (n=92). Isochoric supercooling at -3°C vs. Pre-preservation baseline was evaluated on Resumption of normal spontaneous beating activity. Isochoric supercooling at -3°C enabled 50-65% of human cardiac microtissues to resume normal spontaneous beating activity after 24 to 72 hours of preservation without chemical cryoprotectants.