Decrease in donor heart injury by recombinant clusterin protein in cold preservation with University of Wisconsin solution

Background Donor organ injury during cold preservation before transplantation negatively impacts graft survival. Clusterin (CLU) is a chaperonic protein, and its expression confers donor hearts resistance to cold ischemic injury. This study was conducted to evaluate if the supplement of recombinant CLU protein (rCLU) protects donor organs from injury during cold storage with University of Wisconsin (UW) solution. Methods Human endothelial cell cultures were used as an in vitro model. Heart transplantation in mice was used as an in vivo model. Cell membrane disruption or death was indicated by the release of lactate dehydrogenase (LDH). Donor injury was determined by its functional recovery, and histologic and biochemical analyses. Results Supplement of rCLU to UW solution protected cultured human endothelial cells from cold-induced cell necrosis, as evidenced by a decrease in both release of LDH and the number of ethidium bromide-stained necrotic cells. The protective activity of rCLU was associated with enhanced membrane fluidity at cold temperature. During cold storage of heart organs in UW solution, supplemental rCLU significantly decreased LDH release from heart tissue. In a preclinical model of transplantation, heart grafts after cold preservation with rCLU-containing UW solution had better functional recovery and decreased perivascular inflammation, neutrophil infiltration, and cardiac cell death, including apoptosis and necrosis, that correlated with lower levels of serum creatine kinase and LDH in recipients. Conclusion Our data suggest that supplement of CLU protein in a cold preservation solution may have potential in improving cold preservation of donor organs in transplantation.