Hematopoietic progenitor cells from allogeneic bone marrow transplant donors circulate in the very early post-transplant period.
Despite the therapeutic efficacy of allogeneic bone marrow transplantation (allo-BMT), circulating hematopoietic progenitor cells after bone marrow transplantation have not been well characterized. In the present study, we focused on these 'post-transplant circulating progenitor cells (PTCPC)' which may be on their way to bone marrow. We analyzed the number of myeloid progenitor cells (CFU-GM) per 10 ml of peripheral blood (PB) on days 0 (just before transplantation), 1 (8-15 h after the completion of transplantation), 2, 3, 5, 7, 10, 14, 17, 21, 28 and 35 after allo-BMT in five transplant patients using a standard methylcellulose assay. In addition, high proliferative potential colony-forming cells (HPP-CFC) of the harvested donor bone marrow (BM) and day 1 PB of recipients were assayed in five patients. The origin of HPP-CFC from day 1 PB was analyzed by polymerase chain reaction of a DNA region containing a variable number of tandem repeats. The replating potential of these HPP-CFC was evaluated by a secondary colony assay. The proportion of CD38negative cells among CD34+ cells in the harvested BM and day 1 PB was evaluated by two-color flow cytometric analysis. The number of CFU-GM on day 1 ranged from 6 to 73/10 ml PB, and became undetectable on day 5. The reappearance of PTCPC was observed on day 14, along with hematopoietic recovery. The proportion of HPP-CFC among myeloid colonies from day 1 PB was significantly higher than that from harvested BM (44.3+/-10.4% vs 11.3+/-2.1%, respectively, n=5, P=0.0030). These HPP-CFC from day 1 PB were confirmed to be of donor origin. More than 90% of these HPP-CFC had replating potential. Two-color flow cytometric analysis revealed that the proportion of CD34+CD38negative cells was significantly higher in day 1 PB than in the harvested BM (61.0+/-16.5% vs 9.3+/-3.5%, respectively, n=7, P=0.0002). These observations suggest that both primitive and committed transplanted myeloid progenitor cells may circulate in the very early period following allo-BMT.
Katayama
Y
Y
Second Department of Internal Medicine, Okayama University Medical School, Japan.
Mahmut
N
N
Takimoto
H
H
Maeda
Y
Y
Yano
T
T
Kojima
K
K
Azuma
T
T
Hara
M
M
Imajyo
K
K
Takahashi
S
S
Kai
T
T
Ohno
Y
Y
Miyamoto
T
T
Nagafuji
K
K
Matsue
K
K
Takenaka
K
K
Teshima
T
T
Shinagawa
K
K
Ishimaru
F
F
Omoto
E
E
Harada
M
M
D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D000328:Adult; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000097:blood; D000943:Antigens, Differentiation / Q000097:blood; D001772:Blood Cell Count; D016026:Bone Marrow Transplantation; D003114:Colony-Forming Units Assay; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D007700:Kinetics; D008297:Male; D008562:Membrane Glycoproteins; D018598:Minisatellite Repeats / Q000502:physiology; D009097:Multienzyme Complexes / Q000097:blood; D009244:NAD+ Nucleosidase / Q000097:blood; D013997:Time Factors; D014019:Tissue Donors
D015703:Antigens, CD; D018952:Antigens, CD34; D000943:Antigens, Differentiation; D008562:Membrane Glycoproteins; D009097:Multienzyme Complexes; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D009244:NAD+ Nucleosidase; D051997:ADP-ribosyl Cyclase 1