Reproducible model for kidney autotransplantation in pigs

Several porcine models have been employed to study mechanisms of warm ischemia, cold ischemia, and ischemia reperfusion injury, but the technical/surgical aspects of these models and their possible pitfalls have not been fully described in detail. The goal of the present study was to develop and optimize a porcine kidney autotransplantation model.

Eleven female pigs (24-51 kg) underwent a left ureteronephrectomy. The procured kidney was flushed with 500 mL of histidine-tryptophan-ketoglutarate preservation solution and subsequently cold stored in University of Wisconsin preservation solution. An autotransplantation was performed 18 hours later, following contralateral nephrectomy. Serum creatinine and urine production were assessed posttransplantation. Pigs were sacrificed at 10 days posttransplantation.

Nine pigs showed functioning grafts, immediately producing urine posttransplantation. The serum creatinine values in these pigs followed a bell-shaped curve with peak values at day (D)2-D3. Two renal artery thromboses were observed; the venous anastomosis was prone to stenosis in 6 cases. These technical complications influenced posttransplant observations. Renal artery thrombosis resulted in anuria and increased serum creatinine levels. A stenotic renal vein was associated with a greater peak of serum creatinine. These complications were prevented by modifying the surgical technique accordingly.

We developed and optimized a reproducible model of porcine kidney autotransplantation. Herein we have demonstrated the importance of a proper surgical anastomotic technique to avoid inflow or outflow obstruction that might jeopardize posttransplant kidney function. This clinically relevant model offers the possibility to study various aspects related to kidney preservation without the interference of an allogeneic immune response.