title: Ischemia is the prime but not the only cause of human multipotent stromal cell death in tissue-engineered constructs in vivo.
abstract: Local tissue ischemia is a prime cause responsible for the massive cell death in tissue-engineered (TE) constructs observed postimplantation. To assess the impact of ischemia on the death of implanted human multipotent stromal cells (hMSCs), which have great potential for repairing damaged tissues, we hereby investigated the in vivo temporal and spatial fate of human Luc-GFP-labeled MSCs within fibrin gel/coral scaffolds subcutaneously implanted in nude mice. In vivo bioluminescence imaging monitoring and histological analyses of the constructs tested confirmed the irremediable death of hMSCs over 30 days postimplantation. The kinetics of expression of three hypoxic/ischemic markers (HIF-1α, LDH-A, and BNIP3) was also monitored. Our results provided evidence that hMSCs located within the core of implanted constructs died faster and predominantly and strongly expressed the aforementioned ischemic markers. In contrast, cells located in the outer regions of TE constructs were reperfused by neovascularization and were still viable (as evidenced by their ex-vivo proliferative potential) at day 15 postimplantation. These results support the explanation that in the central part of the constructs tested, death of hMSCs was due to ischemia, whereas in the periphery of these constructs, cell death was due to another mechanism that needs to be elucidated.
authors.affiliation: Laboratory of Bioengineering and Biomechanics for Bone and Articulations, UMR 7052 CNRS, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Becquart
authors.forename: Adeline
authors.initials: A
authors.lastname: Cambon-Binder
authors.forename: Laurent-Emmanuel
authors.initials: LE
authors.lastname: Monfoulet
authors.forename: Marianne
authors.initials: M
authors.lastname: Bourguignon
authors.forename: Katleen
authors.initials: K
authors.lastname: Vandamme
authors.forename: Morad
authors.initials: M
authors.lastname: Bensidhoum
authors.forename: Hervé
authors.initials: H
authors.lastname: Petite
authors.forename: Delphine
authors.initials: D
authors.lastname: Logeart-Avramoglou
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D000080864:Lactate Dehydrogenase 5; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D023822:Tissue Engineering / Q000379:methods
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D000080864:Lactate Dehydrogenase 5