title: Human cord cell hematopoiesis in three-dimensional nonwoven fibrous matrices: in vitro simulation of the marrow microenvironment.
abstract: Current hematopoietic culture systems mainly utilize two-dimensional devices with limited ability to promote self-renewal of early progenitors. In vivo-like three-dimensional (3-D) culture environments might be conducive to regulating stem cell proliferation and differentiation similar to in vivo hematopoiesis. The few 3-D cultures reported in the literature either produced few progenitors or provided little information about microenvironment. In this study, we constructed a 3-D hematopoietic microenvironment composed of nonwoven matrix and human cord blood (CB) cells to simulate the marrow microenvironment and expand cord progenitors. Nonwoven polyethylene terephthalate (PET) fabric with defined microstructure was used as the 3-D scaffold and the PET surface was modified by hydrolysis to improve cell adhesion. Different cell organizations were formed in a 3-D matrix in a developmental manner, from individual cells and cells bridging between fibers to large cell aggregates. Both stromal and hematopoietic cells were distributed spatially within the scaffold. Compared to two-dimensional (2-D) CD34(+) cell culture, 3-D culture produced 30-100% higher total cells and progenitors without exogenous cytokines. With thrombopoietin and flt-3/flk-2 ligand, it supported two- to three-fold higher total cell number (62.1- vs. 24.6-fold), CD34(+) cell number (6.8- vs. 2.8-fold) and colony-forming unit (CFU) number for 7-9 weeks (n = 6), indicating a hematopoiesis pathway that promoted progenitor production. Culture in 3-D nonwoven matrices enhanced cell-cell and cell-matrix interactions and allowed 3-D distribution of stromal and hematopoietic cells. The formation of cell aggregates and higher progenitor content indicated that the spatial microenvironment in 3-D culture played an important role in promoting hematopoiesis. This 3-D culture system can be used as an in vitro model to study stem cell or progenitor behavior, and to achieve sustained progenitor expansion.
authors.affiliation: Department of Chemical Engineering, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: T
authors.initials: T
authors.lastname: Ma
authors.forename: D A
authors.initials: DA
authors.lastname: Kniss
authors.forename: S T
authors.initials: ST
authors.lastname: Yang
authors.forename: L C
authors.initials: LC
authors.lastname: Lasky
mesh_terms: D001672:Biocompatible Materials; D002452:Cell Count; D018929:Cell Culture Techniques / Q000295:instrumentation*; D002455:Cell Division; D002478:Cells, Cultured; D018920:Coculture Techniques; D003114:Colony-Forming Units Assay; D003470:Culture Media; D017077:Culture Media, Conditioned / Q000737:chemistry; D005312:Fetal Blood / Q000166:cytology*; D005947:Glucose / Q000032:analysis; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007773:Lactates / Q000737:chemistry; D008422:Materials Testing; D008565:Membrane Proteins / Q000494:pharmacology; D011093:Polyethylene Terephthalates; D017154:Stromal Cells / Q000166:cytology; D013499:Surface Properties; D013535:Suspensions; D013926:Thrombopoietin / Q000494:pharmacology
chemical_list: D001672:Biocompatible Materials; D003470:Culture Media; D017077:Culture Media, Conditioned; D007773:Lactates; D008565:Membrane Proteins; D011093:Polyethylene Terephthalates; D013535:Suspensions; C084881:flt3 ligand protein; D013926:Thrombopoietin; D005947:Glucose