Tertiary lymphoid organs (TLOs) are ectopic lymphoid structures with immunomodulatory effects that develop in chronic inflammatory conditions, including transplantation, cancer, autoimmune diseases and infections. Now, Martin Oberbarnscheidt and coauthors report that TLOs contribute to rejection of kidney allografts.

In recipients with normal secondary lymphoid tissues, the allograft survival of F1-RIP-LTα kidneys with preformed TLOs was significantly shorter than that of kidneys that did not have TLOs at the time of transplantation, suggesting that TLOs accelerate graft rejection. TLOs were present in all of the rejected allografts. Furthermore, in an acute rejection model, knockout of LTβR in donor mice prevented intragraft TLO formation and prolonged allograft survival.