title: Microvessel-like structures from outgrowth endothelial cells from human peripheral blood in 2-dimensional and 3-dimensional co-cultures with osteoblastic lineage cells.
abstract: Tissue regeneration involves complex processes in the interaction between different cell types that control the process of neo-vascularization. In bone, osteoblasts and bone marrow stem cells provide cue elements for the proliferation of endothelial cells, differentiation of endothelial precursors, and the maturation of a vascular network. In this study, we investigated outgrowth endothelial cells (OECs), a potential source of autologous endothelial cells derived from human peripheral blood, in direct 2-dimensional (2-D) and 3-D co-culture systems with cells relevant for the regeneration of bone tissue, such as osteoblasts. In the co-cultures, OECs were evaluated in terms of their stability as an endothelial population at the single cell level using flow cytometry and their ability to establish a pre-vascular network at the light-microscopical and ultra-structural level. In co-cultures with the osteoblast cell line MG63 and with human primary osteoblasts (pOBs), OECs, in contrast to human umbilical vein endothelial cells, formed highly organized microvessel-like structures. These microvessel-like structures included the formation of a vascular lumen with tight junctional complexes at intercellular contacts of endothelial cells. In the co-culture, the formation of this vascular network was achieved in the standard growth medium for OECs. Furthermore, using a rotating culture vessel system, 3-D co-cultures consisting of OECs and pOBs were generated. Based on these observations, we conclude that OECs could provide a valuable source of autologous endothelial cells for the generation of complex tissue-engineered tissues.
authors.affiliation: Institute of Pathology, Johannes Gutenberg University, Mainz, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Fuchs
authors.forename: Alexander
authors.initials: A
authors.lastname: Hofmann
authors.forename: C   James
authors.initials: C
authors.lastname: Kirkpatrick
mesh_terms: D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods*; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000166:cytology* / Q000502:physiology; D008833:Microcirculation / Q000166:cytology* / Q000254:growth & development*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology; D023822:Tissue Engineering / Q000379:methods*