Targeted Protection of the Colon in the Absence of Donor Antigen-Presenting Cell -Derived Interleukin 23 Allows for Separation of Graft Versus Host and Graft Versus Leukemia Effects

Abstract

Separation of graft versus leukemia (GVL) and graft versus host (GVH) reactivity has been a longstanding but elusive goal in allogeneic bone marrow transplantation (BMT). Recent studies from our laboratory have shown that donor APC-derived IL-23 secretion has a critical role in mediating pathological damage in the colon during GVHD, but has no protective effect in other GVHD target organs such as the lung and liver. These results demonstrate the feasibility of regional GVHD protection and raise the question as to whether such localized protection might be a strategy to separate GVH and GVL responses.