Self-assembling peptide hydrogels mitigate hypothermic injury during short-term storage of anchorage-dependent cell therapies

To improve the clinical translation of cell-based therapies there is a growing need for biomaterials that serve dual functions: preserving cell viability during storage and enabling direct delivery without additional processing at the point of care. Unlike cryopreservation, which requires cytotoxic cryoprotectants and complex thawing steps, hypothermic storage (1–35 °C) offers a simple and cost-effective cell preservation alternative. However, hypothermic cell injury remains a major barrier to the prolonged storage of cell therapies, limiting their clinical utility. Here, we present injectable, bioactive self-assembling peptide (SAP) hydrogels as a dual-function platform for hypothermic preservation and localized delivery of retinal pigment epithelial (ARPE-19) cells. Encapsulation within SAP hydrogels that mimic the extracellular matrix (ECM) sustained high cell viability and minimized intracellular reactive oxygen species (ROS) accumulation after 3-day storage at 15 °C, outperforming non-bioactive controls. Despite reduced ROS, mitochondrial membrane potential declined significantly, identifying mitochondrial dysfunction as a key driver of hypothermic injury. Importantly, the shear-thinning behavior of SAP hydrogels enabled minimally invasive injection and precise cell localization in in vitro delivery models. These findings establish bioactive peptide hydrogels as a promising strategy for cold-chain storage and targeted administration of anchorage-dependent cell therapies, addressing critical challenges in clinical translation.