The scientific “discovery” of graft versus host disease (GVHD) mirrors some aspects of this devastating disease. It is based on an accurate observation but an error in interpretation. Similarly, GVHD and in particular chronic GVHD confront patients as a paradox. The symptoms appear just when he or she believes to be cured from the previously diagnosed lethal disease, that is, at engraftment of the healthy donor cells. GVHD can have devastating effects on patients, families, and transplant teams. Conversely, few “man made diseases” have provided so much insight into basic immunobiology as GVHD. It is the hope of this book, to turn the knowledge gained from chronic GVHD into benefit for all patients after a hematopoietic stem cell transplant (HSCT) and for the large population of patients with autoimmune disorders or cancer in general.

THE BEGINNING OF HSCT

The old Greek proverb that “war is the father of all goods” applies to few medical technologies as well as it does to HSCT. The recognition of late bone marrow failure from atomic bomb exposure in Hiroshima and Nagasaki had double consequences. Vast research funds were allotted to find tools to overcome this lethal late complication of high dose radiation exposure. Results came rapidly. As early as 1949, Jacobson showed in his pioneering work that mice survived otherwise lethal total body irradiation when their spleens were shielded during radiation exposure. Humoral, spleen-derived products were believed to be protective.