The potential of patients' peripheral blood mononuclear cells to differentiate into dendritic cells after hematopoietic stem cell transplantation.
OBJECTIVE
Although hematopoietic stem cell transplantation (HSCT) is a curative treatment for many hematological disorders, there is persistent immunosuppression in both allogeneic and autologous HSCT. Dendritic cells (DCs) play key roles in the immune system. This study investigated whether the DC progenitor cells within patients' peripheral blood after HSCT have the potential to differentiate into DCs.


METHODS
Twenty-eight patients were included in this study, and peripheral blood samples were basically taken before starting the conditioning regimen, on the day of transplantation (day 0), and on days +14, +28, +42, +70 and +170 after transplantation. Immature DCs (iDCs) were induced from adherent mononuclear cells by using recombinant human granulocyte-macrophage colony-stimulating factor plus interleukin-4.


RESULTS
The iDCs expressed cell surface antigens such as CD40 and HLA-DR, and they had phagocytotic activity, thus showing the characteristics of iDCs. The induction of iDCs was possible from day +14 after HSCT. However, there were differences between allogeneic and autologous HSCT in the expression of CCR5 in iDCs at day +14 after transplantation. Furthermore, the up-regulation of maturation-related antigens by maturation stimuli was higher after HSCT compared with before HSCT.


CONCLUSIONS
We demonstrated that patients' peripheral blood mononuclear cells have the potential to differentiate into DCs beginning on day +14 after HSCT, although some differences exist between allogeneic and autologous HSCT and between before and after HSCT.
Department of Radiological Life Sciences, Division of Medical Life Sciences, Hirosaki University Graduate School of Health Sciences, Aomori 036-8564, Japan.
Hironori
H
Yoshino
Naoki
N
Watanabe
Kenji
K
Takahashi
Kazuto
K
Ogura
Tomoaki
T
Akagi
Kohmei
K
Kubo
Ikuo
I
Kashiwakura
D000293:Adolescent; D000328:Adult; D019013:CD40 Antigens / Q000378:metabolism; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000378:metabolism*; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006684:HLA-DR Antigens / Q000378:metabolism; D006402:Hematologic Diseases / Q000628:therapy*; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010587:Phagocytosis; D013997:Time Factors; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous
D019013:CD40 Antigens; D006684:HLA-DR Antigens; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor