Replicative stress after allogeneic bone marrow transplantation: changes in cycling of CD34+CD90+ and CD34+CD90- hematopoietic progenitors.
To further characterize hematopoietic "replicative stress" induced by bone marrow transplantation (BMT), the cell-cycle status of CD90+/- subsets of marrow CD34+ cells obtained 2 to 6 months after transplantation from 11 fully chimeric recipients was examined. Cycling profiles, derived by flow cytometry after staining with Hoechst 33342 and pyronin Y, were compared with those of 14 healthy marrow donors. Primitive CD34+CD90+ cells represented a smaller proportion of CD34+ cells in recipients (10% +/- 4% versus 19.6% +/- 5.3% in donors; P <.0001) and were more mitotically active, with the proportion of cells in S/G2/M nearly 4-fold higher than in donors (15.6% +/- 3% and 4.4% +/- 1.6%, respectively; P <.0001). By comparison, there was a modest increase in the proportion of CD34+CD90- progenitors in S/G2/M after BMT (10.9% +/- 1% vs 9.6% +/- 2% in donors; P =.04). Replicative stress after BMT is borne predominantly by cells in a diminished CD34+CD90+ population.
Division of Hematology/Oncology, The Hospital for Sick Children, and the Department of Medical Oncology and Hematology, University Health Network, University of Toronto, Ontario, Canada.
I
I
Thornley
D R
DR
Sutherland
R
R
Nayar
L
L
Sung
M H
MH
Freedman
H A
HA
Messner
D000328:Adult; D018952:Antigens, CD34 / Q000502:physiology; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology; D016026:Bone Marrow Transplantation / Q000502:physiology*; D002453:Cell Cycle / Q000502:physiology*; D002455:Cell Division / Q000276:immunology / Q000502:physiology; D005434:Flow Cytometry; D005500:Follow-Up Studies; D019337:Hematologic Neoplasms / Q000628:therapy; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D018800:Thy-1 Antigens / Q000502:physiology; D014184:Transplantation, Homologous / Q000502:physiology
D018952:Antigens, CD34; D018800:Thy-1 Antigens