Ex vivo manipulation of umbilical cord blood-derived hematopoietic stem/progenitor cells with recombinant human stem cell factor can up-regulate levels of homing-essential molecules to increase their transmigratory potential.
OBJECTIVE
The cause of delayed hematopoietic reconstitution after umbilical cord blood transplantation (UCBT) remains controversial. We hypothesized that hematopoietic stem/progenitor cells (HS/PCs) from UCB have some defects of the homing-related molecules responsible for their slow engraftment.


METHODS
A homing-related molecule repertoire expressed on HS/PCs from fresh and cryopreserved UCB, mobilized peripheral blood (mPB), and bone marrow (BM) were compared using sensitive, four-color fluorescence-activated cell sorting analysis. Purified CD34+ cells were subjected to ex vivo transmigration through double-coated transwell filter inserts, and an in vivo homing assay was performed in xenotransplanted NOD/SCID mice.


RESULTS
UCB-derived CD34(bright) cells expressed significantly lower levels of CD49e, CD49f, and CXCR-4 than their mPB and BM counterparts. CD34+ cells from UCB (and BM) exhibited significantly lower ex vivo transmigration than those from mPB, which were largely blocked by neutralizing antibodies to CD49e or CD49f. Recombinant human tumor necrosis factor-alpha treatment enhanced ex vivo transmigration of CD34+ cells from UCB and BM by inducing expression of the matrix metalloproteinases MMP-2/MMP-9. Short-term treatment of UCB-derived CD34+ cells with rHu-stem cell factor (rHuSCF) up-regulated levels of the homing-related molecules with their increased ex vivo transmigratory and in vivo homing potential.


CONCLUSIONS
Our results indicate that disadvantageous transmigratory behavior of HS/PCs from UCB, which might partly explain the delayed reconstitution after UCBT, can be reversed by ex vivo manipulation with rHuSCF.
Zheng
Yizhou
Y
Division of Cell Processing, Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Watanabe
Nobukazu
N
Nagamura-Inoue
Tokiko
T
Igura
Koichi
K
Nagayama
Hitomi
H
Tojo
Arinobu
A
Tanosaki
Ryuji
R
Takaue
Yoichi
Y
Okamoto
Shinichiro
S
Takahashi
Tsuneo A
TA
D000818:Animals; D015815:Cell Adhesion Molecules / Q000096:biosynthesis; D018929:Cell Culture Techniques / Q000379:methods; D002633:Chemotaxis / Q000187:drug effects*; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D006085:Graft Survival; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D016023:Integrins / Q000096:biosynthesis; D008666:Metalloendopeptidases / Q000096:biosynthesis; D051379:Mice; D016513:Mice, SCID; D019707:Receptors, Chemokine / Q000096:biosynthesis; D011994:Recombinant Proteins; D019089:Stem Cell Factor / Q000494:pharmacology*; D014183:Transplantation, Heterologous; D015854:Up-Regulation / Q000187:drug effects*
D015815:Cell Adhesion Molecules; D016023:Integrins; D019707:Receptors, Chemokine; D011994:Recombinant Proteins; D019089:Stem Cell Factor; D008666:Metalloendopeptidases