To analyze in some depth the association between GvHD and proportions/numbers of CD4+CD25high cells in the blood the entire group of patients was subdivided into three subgroups according to the manifestation of aGvHD: (I) absent; (II) appearing at hematologic recovery; or (III) appearing at a later time point post-transplant. The gene discussed is CD4; the disease is graft versus host disease.