Acute graft-versus-host disease - Biologic process, prevention, and therapy

The allogeneic transplantation of hematopoietic cells is a well-established treatment for hematologic diseases that cannot be cured with conventional treatments.1 More than 1 million hematopoietic-cell transplantations have been performed, of which 40% were allogeneic.2 The most common life-threatening complication is graft-versus-host disease (GVHD), which occurs when immunocompetent T cells in the donated tissue (the graft) recognize the recipient (the host) as foreign. The resulting immune response activates donor T cells to gain cytolytic capacity and to then attack the recipient to eliminate foreign antigen-bearing cells. The two main clinical presentations are acute GVHD and chronic GVHD. This review focuses on acute GVHD.