Different Immune Reconstitution between Cord Blood and unrelated Bone Marrow Transplantation with Relation to Chronic Graft-versus-Host Disease

Background: advances of allogeneic hematopoietic cell transplantation (allo hct) have brought long term survival to the patients with hematologic malignancies. chronic graft versus host disease (gvhd) is one of major problems for the long survivors after allo hct. dysregulation of immune reconstitution has been reported to be i nvolved in the pathogenesis of chronic gvhd. differences of immune reconstitution between cord blood transplantation (cbt) and unrelated bone marrow transplantation (ubmt) remain unclear in long term survivors. we investigated immune reconstitution in pa tients who survive for more than 2 years after cbt (n=21) or ubmt (n=20) without relapse of underlying disease. materials and methods: using flowcytomeric analysis of peripheral blood, we investigated immune reconstitution of t cells, b cells, and nk cells between cbt and ubmt patients. we collected clinical data regarding allo hct and examined the relation of immune reconstitution to the development of chronic gvhd. results: between cbt and ubmt patients, we found significant differences in absolute cell number of cd8+ as well as cd19+ cell and cd4/cd8 ratio even more than 2 years after allo hct. among ubmt patients, absolute cell number of naïve cd4+ cell was significantly lower in patients with chronic gvhd. in addition, we found significant difference s in absolute cell number of cd19+ cell, especially naïve b cell between patients with and without chronic gvhd in both cbt and ubmt patients. conclusion: these results suggest that differences of immune recovery between cbt and ubmt patients may exist e ven in patients who survive for more than 2 years and might be related to the development of chronic gvhd.