Desensitizing With Temporary Donor Splenic Transplant: Hope for the Sensitized Patients on Pancreas and Kidney -Pancreas Transplant Waitlist

Background. Sensitized patients on a waitlist with donor specific antibodies (DSA) or positive flow cytometry cross match (FXM) to deceased donor organ have few pretransplant desensitization options due to increasing graft cold ischemia time. Herein, sensitized simultaneous kidney/ pancreas recipients received temporary splenic transplant from the same donor under the hypothesis that spleen would function as a DSA graveyard and provide a safe immunologic window for transplant.Methods. We analyzed presplenic and postsplenic transplant FXM and DSA results of 8 sensitized patients who underwent simultaneous kidney and pancreas transplantation with temporary deceased donor spleen between November 2020 and January 2022. Results. Pre-splenic transplant, 4 sensitized patients were both T-cell and B-cell FXM positive; one was only B-cell FXM positive and 3 were DSA positive/FXM negative. Post-splenic transplant, all were FXM negative. Pre-splenic transplant class I and class II DSA were detected in 3 patients, only class I DSA in 4 patients, and only class II DSA in 1 patient. Postsplenic transplant, class I DSA was eliminated in all patients. Class II DSA persisted in 3 patients; all showed a marked decrease in DSA mean fluorescence index. Class II DSA was eliminated in one patient.Conclusion. Donor spleen functions as a DSA graveyard and provides an immunologically safe window for kidney-pancreas transplantation.