ABSTRACT
Graft-vs.-host disease (GVHD) remains one the major obstacles to successful allogeneic
hematopoietic cell transplantation (HCT). GVHD is a major cause of morbidity and mor-
tality even when recipient and donor are matched at the major histocompatibility complex
(MHC) termed HLA in humans (1,2). In its acute and chronic forms, GVHD has an
important impact on survival and the recipient’s quality of life (3,4). The ability to prevent
GVHD, i.e., the application of successful prophylaxis, is the cornerstone of success-
treatment when prophylaxis fails is suboptimal. Previous chapters have dealt with the
pathophysiology of GVHD, and based on insights from these important studies, investi-
gators have attempted to develop effective preventive strategies.
