245.2: Evaluation of Methods to Obtain Peripheral Blood Mononuclear Cells From Deceased Donors Adjacent to Organ Procurement for Tolerance-Induction Protocols

Abstract

Regulatory cell therapies have shown promise in tolerance-induction protocols in living donor organ transplantation. These protocols should be pursed in deceased-donor transplantation. Donor peripheral mononuclear cells (PBMCs) are an optimal source of donor antigens for the induction of donor-specific regulatory cells that are more effective than antigen non-specific regulatory cells. During the development of a regulatory cell tolerance induction protocol with organs from deceased donors, we compared three methods of obtaining PBMCs from deceased donors focusing on: cell yield, viability, and contamination of unwanted cell types. PBMC procurement methods: During organ procurement at the time of cold perfusion, blood was collected from the vena cava and placed into a 10-liter blood collection bag, and thereafter transported to Karolinska University Hospital, where leukapheresis was performed (BCL) n=7. Blood was collected via the vena cava into blood donation bags before cold perfusion. The bags underwent buffy coat separation and thereafter automated leukocyte isolation using SEPAX (BCS) n=2.To collect PBMCs, leukapheresis was performed via a central dialysis catheter on deceased donors in the ICU prior to the organ procurement procedure (LEU) n=9. Our results show that all methods were safe in relation to the intended organ procurement procedure. LEU is a feasible method to obtain PBMC from deceased donors. LEU tend to have higher yield of donor PBMC/kg compared to BCS and BCL and acceptable level of granulocyte contamination compared to BCS. Further investigations including the quality of the cell products that was manufactured with PBMCs from these methods will be needed to determine which approach is the most suitable for tolerance induction protocols.