CD26 is essential for normal G-CSF-induced progenitor cell mobilization as determined by CD26-/- mice.
OBJECTIVE
In spite of the wide usage of mobilized peripheral blood hematopoietic stem and progenitor cells (HSC/HPC) for transplantation, the mechanism of granulocyte colony-stimulating factor (G-CSF)-induced HSC/HPC mobilization has yet to be fully determined. Our previous studies suggested that that G-CSF-induced mobilization may involve the extracellular peptidase CD26 (DPPIV/dipeptidylpeptidase IV). We set out to establish whether CD26 was an essential component of normal G-CSF-induced mobilization of HSC/HPC.


METHODS
Normal wild-type (WT) control C57BL/6 mice and CD26 knockout (CD26(-/-)) mice, also on a C57BL/6 background, were treated with or without G-CSF and peripheral blood cells, bone marrow cells, and spleen cells were assessed for CFU-GM, BFU-E, and CFU-GEMM content.


RESULTS
No statistical difference in the number of CFU-GM, BFU-E, or CFU-GEMM in the peripheral blood, bone marrow, or spleen of untreated WT vs untreated CD26(-/-) mice was observed. G-CSF treatment of WT mice resulted in the mobilization of HPC into the peripheral blood. The number of HPC detected in G-CSF-treated CD26(-/-) mouse peripheral blood was significantly less than the corresponding number of HPC detected in G-CSF-treated WT mouse peripheral blood after either a 2- or 4-day G-CSF regimen.


CONCLUSIONS
CD26 plays a critical role in G-CSF-induced mobilization of HPC.
Department of Microbiology/Immunology and the Walther Oncology Center, Indiana University School of Medicine, and the Walther Cancer Institute, Indianapolis, Ind. 46202-5254, USA.
Kent W
KW
Christopherson
Scott
S
Cooper
Giao
G
Hangoc
Hal E
HE
Broxmeyer
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D002452:Cell Count; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000502:physiology; D018819:Dipeptidyl Peptidase 4 / Q000502:physiology*; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D019650:Hematopoietic Stem Cell Mobilization; D051379:Mice; D008810:Mice, Inbred C57BL
D054377:Chemokine CXCL12; D019743:Chemokines, CXC; C515256:Cxcl12 protein, mouse; D016179:Granulocyte Colony-Stimulating Factor; D018819:Dipeptidyl Peptidase 4