Xenothymokidney Maintained for 2 Months in Brain-Dead Decedent

At the American Transplant Congress 2024, Jeffrey Stern, MD, discussed the case of a brain-dead decedent in whom an alpha-gal knockout porcine kidney with thymus autograft (alpha Gal-KO xenothymokidney) was maintained for 2 months. The presentation won the People’s Choice Award for most impactful plenary abstract.

The brain-dead decedent had bilateral native nephrectomies and transplantation of a Gal-KO xenothymokidney utilizing a clinically approved immunosuppression regimen. Researchers measured the decedent’s urine output (UOP), serum creatinine (sCr), 6-hour urine creatinine clearance (6CrCl), and 24-hour urine creatinine clearance throughout the 2-month period. They performed protocol and for-cause biopsies on days 10, 14, 21, 28, 33, 45, 49, 56, and 61.

UOP was healthy upon xenothymokidney implantation, at 4.76 L/day (range 1.1-19.8 L/day). The decedent’s sCr reached its lowest point of 0.32 mg/dL on day 13, corresponding with a 6CrCl of 156 mL/min. The day 10, 14, 21, and 28 biopsies found no evidence of rejection. However, sCr rose to a peak of 0.7 mg/dL (6CrCl of 65.6 mL/min) between days 29 and 33, and the day 33 biopsy identified antibody-mediated rejection (AMR).

The decedent subsequently received plasmapheresis, high-dose corticosteroids, rabbit antithymocyte globulin, and pegcetacoplan. After this treatment regimen, sCr and CrCl improved to 0.18 mg/dL and 111.9 mL/min, respectively. Biopsy showed that microvascular injuries were resolved, and renal scintigraphy measured the final glomerular filtration rate as 150 mL/min.

In sum, the Gal-KO xenothymokidney functioned in the brain-dead decedent for 2 months and AMR was treated successfully.

Source: Stern JM, Kim J, Tatapudi V, et al. Normal function and successful treatment of rejection in a xenothymokidney maintained for 2 months in a brain-dead decedent. Abstract #245. Presented at the American Transplant Congress 2024; June 1-5, 2024; Philadelphia, Pennsylvania.