Draining Lymph Nodes in Human Kidney Pancreas Transplant: Potential Implications in Alloimmunity and Tolerance

•Pancreas transplant is effective for insulin-dependent diabetes.•Primary immune events in immune regulatory lymph nodes in human pancreas transplants are unknown.•Availability of relevant draining lymph nodes from clinical archiving is essential. Draining lymph nodes (DLNs) are implicated in alloimmunity and tolerance regulation. The role of DLNs in human organ transplant is unknown due to the lack of relevant clinical tissues. During a combined kidney and pancreas transplant, the distal vena cava and both right and left common and external iliac vessels were mobilized and exposed. Draining lymph nodes along these vessels were removed sequentially and archived before the pancreas transplant. Similarly, the DLNs along the left iliac vessels were removed and archived before implantation of the kidney allograft. Among 13 patients undergoing kidney and pancreas transplants, 6 had pre- and postreperfusion DLNs clinically archived. The remaining 7 either had only prereperfusion DLNs archived or none. Clinical archiving of DLNs did not alter operative times or parameters. This study describes an approach for clinical archiving of DLNs obtained within the operative field during combined kidney–pancreas transplant in humans. The availability of relevant DLNs is essential for investigating fundamental initial primary immune responses potentially important in allograft alloimmunity and tolerance.