title: Stem cell factor improves SCID-repopulating activity of human umbilical cord blood-derived hematopoietic stem/progenitor cells in xenotransplanted NOD/SCID mouse model.
abstract: Poor in vivo homing capacity of hematopoietic stem/progenitor cells (HS/PCs) from umbilical cord blood (UCB) can be reversed by short-term ex vivo manipulation with recombinant human stem cell factor (rHuSCF). This study was designed to evaluate the effect of ex vivo manipulation of UCB-derived HS/PCs with rHuSCF on human cell engraftment rates in xenotransplanted NOD/SCID mouse model. The human cell engraftment rates in xenotransplanted primary and secondary NOD/SCID mice were characterized using four-color flow cytometric analysis and progenitor assay. Grafts of rHuSCF-treated UCB CD34(+) cells resulted in significantly higher levels of human cell engraftment than that of nontreated ones in both xenotransplanted primary and secondary NOD/SCID recipients. Fresh UCB CD34(+) cells did not express either of the matrix metalloproteinase (MMP) family members MMP-2 or MMP-9. rHuSCF-treated UCB CD34(+) cells expressed significant levels of MMP-2 and MMP-9. Pretreatment of UCB CD34(+) cells with the specific MMP inhibitor completely blocked human cell engraftment in xenotransplanted NOD/SCID recipients. Our results indicate that ex vivo manipulation of human HS/PCs with rHuSCF might provide an optimal approach to develop more effective stem cell-based therapies in situations where engraftment is delayed due to limiting HS/PCs number, for example, UCB transplantation.
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Science & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zheng
authors.forename: A
authors.initials: A
authors.lastname: Sun
authors.forename: Z C
authors.initials: ZC
authors.lastname: Han
mesh_terms: D000818:Animals; D018952:Antigens, CD34; D018929:Cell Culture Techniques; D002465:Cell Movement; D036101:Cord Blood Stem Cell Transplantation / Q000379:methods*; D006085:Graft Survival; D006801:Humans; D016130:Immunophenotyping; D020778:Matrix Metalloproteinase 2 / Q000032:analysis; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D023421:Models, Animal; D019089:Stem Cell Factor / Q000494:pharmacology*; D014183:Transplantation, Heterologous / Q000379:methods*
chemical_list: D018952:Antigens, CD34; D019089:Stem Cell Factor; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9