Protecting Cells From the Cold With Sugar: Low-DMSO Freezing Method Aims to Overcome CAR-T Shipping Bottleneck

CAR-T therapy is challenging not only to manufacture, but also to deliver still-active cells to the bedside. These “living drugs” are often produced at centralized facilities, then frozen and shipped over long distances. If the cells are damaged during freezing and thawing, both the usable dose and their function may be reduced by the time they reach the hospital. An MIT research team is now attempting to use two common sugars to share the burden of cryoprotection, with the aim of simplifying handling procedures before treatment.

Current cryopreservation formulations typically rely on dimethyl sulfoxide (DMSO) to inhibit ice-crystal formation and prevent damage to cell membranes. However, DMSO may harm cells and, because of formulation and administration requirements, may need to be reduced or removed before infusion. The washing process itself can also cause cell loss while increasing the staffing and equipment burden on healthcare institutions.

The team selected trehalose and sucrose as the primary cryoprotective components. These sugars can stabilize proteins and reduce ice-crystal damage, but they do not readily cross cell membranes on their own. The researchers therefore used brief electrical currents to perform electroporation, opening temporary channels in the cell membrane so the sugars could enter the cells. The new formulation still retains a small amount of DMSO and is not completely DMSO-free; the research team’s concept is to lower the concentration to a level that does not require separate removal after thawing.

The experiments covered CAR-T cells and mesenchymal stem cells with regenerative medicine potential. According to the study results, cells using sugars as the primary protectants had higher survival rates after freezing and thawing. The researchers further used the thawed CAR-T cells in mouse models of non-Hodgkin lymphoma and glioblastoma. Animals that received cells preserved with the new formulation showed better survival than the control group that received cells preserved using the conventional DMSO method.

The significance of this work extends beyond improving a laboratory metric. If the cells can be used directly after thawing, hospitals may be able to eliminate a washing and recovery step while also reducing dose loss during handling. However, this does not mean CAR-T can already be distributed like conventional medicines: the cells still require low-temperature storage and transportation, electroporation adds another manufacturing step, and the entire process must still be shown to maintain consistency, sterility, and potency in large-scale production.

The efficacy evidence currently comes from mice, and no other independent sources were found to cross-check the same event. As a next step, the research team hopes to collaborate with hospitals to test whether this method can be integrated into actual manufacturing and thawing workflows. Small human trials may become possible only after cell quality, function, safety, and process validation have all met the necessary standards. Whether sugar can truly ease the burden on the CAR-T supply chain will depend not only on whether the cells can withstand low temperatures, but also on whether the new process can meet clinical-grade manufacturing and regulatory requirements.