Recent advances in the pathophysiology and treatment of GVHD.

Graft-versus-host disease (GVHD) remains a major complication of allogeneic hematopoietic cell transplantation. Recent biological insights have led to a reevaluation of GVHD. It is now recognized not merely as a donor-derived immune attack, but as a complex disease characterized by the disruption of tolerance in target tissues and abnormal immune reconstitution. Therapeutic approaches are shifting from broad, nonspecific immunosuppression toward mechanism-based targeted therapies, active management of immune reconstitution, and biomarker-based risk stratification. To optimize patient outcomes, it is essential to incorporate these evolving pathophysiological mechanisms and new therapeutic strategies into clinical practice.