Peyer patches are not required for acute graft-versus-host disease after myeloablative conditioning and murine allogeneic bone marrow transplantation

Abstract
Graft-versus-host disease (GVHD) is a multistep disease process following allogeneic bone marrow transplantation (BMT). It has been postulated that the induction of acute GVHD requires the presence of Peyer patches (PPs). A new tumor necrosis factor (TNF)–deficient strain has been developed that totally lacks PPs and displays the defects characteristic of TNF ablation but not lymphotoxin-associated defects characterized by lack of both PPs and lymph nodes. To determine the necessity of PPs in acute lethal GVHD induction, we transplanted full major histocompatibility complex (MHC)–mismatched grafts into myeloablated TNF knockout recipients. No differences in the survival or GVHD-associated histopathologic lesions were observed between the recipients. We conclude that neither PPs nor host TNF-α is required for the development of acute lethal GVHD in mice that undergo myeloablative conditioning and allogeneic BMT.