Bone marrow B cell precursor number after allogeneic stem cell transplantation and GVHD development.

Department of Pathology and Laboratory Medicine, The University of North Carolina, Chapel Hill, NC 27599, USA.
Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation (Impact Factor: 3.15). 03/2012; 18(6):968-73. DOI: 10.1016/j.bbmt.2012.03.005
Source: PubMed

ABSTRACT Patients without chronic graft-versus-host disease (cGVHD) have robust B cell reconstitution and are able to maintain B cell homeostasis after allogeneic hematopoietic stem cell transplantation (HSCT). To determine whether B lymphopoiesis differs before cGVHD develops, we examined bone marrow (BM) biopsies for terminal deoxynucleotidyl transferase (TdT) and PAX5 immunostaining early post-HSCT at day 30 when all patients have been shown to have high B cell activating factor (BAFF) levels. We found significantly greater numbers of BM B cell precursors in patients who did not develop cGVHD compared with those who developed cGVHD (median = 44 vs 2 cells/high powered field [hpf]; respectively; P < .001). Importantly, a significant increase in precursor B cells was maintained when patients receiving high-dose steroid therapy were excluded (median = 49 vs 20 cells/hpf; P = .017). Thus, we demonstrate the association of BM B cell production capacity in human GVHD development. Increased BM precursor B cell number may serve to predict good clinical outcome after HSCT.

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