Thanks to its biological properties, the human amniotic membrane (HAM) can be used as a barrier membrane for guided bone regeneration (GBR). However, no study has assessed the influence of the preservation method of HAM for this application. This study aimed to establish the most suitable preservation method of HAM for GBR. Fresh (F), cryopreserved (C) lyophilized (L), and decellularized and lyophilized (DL) HAM were compared. The impact of preservation methods on collagen and glycosaminoglycans (GAG) content was evaluated using Masson's trichrome and alcian blue staining. Their suture retention strengths were assessed. In vitro, the osteogenic potential of human bone marrow mesenchymal stromal cells (hBMSCs) cultured on the four HAMs was evaluated using alkaline phosphatase staining and alizarin red quantification assay. In vivo, the effectiveness of fresh and preserved HAMs for GBR was assessed in a mice diaphyseal bone defect after 1 week or 1 month healing. Micro‐CT and histomorphometric analysis were performed. The major structural components of HAM (collagen and GAG) were preserved whatever the preservation method used. The tearing strength of DL‐HAM was significantly higher. In vitro, hBMSCs seeded on DL‐HAM displayed a stronger ALP staining, and alizarin red staining quantification was significantly higher at Day 14. In vivo, L‐HAM and DL‐HAM significantly enhanced early bone regeneration. One month after the surgery, only DL‐HAM slightly promoted bone regeneration. Several preserving methods of HAM have been studied for bone regeneration. Here, we have demonstrated that DL‐HAM achieved the most promising results for GBR.
We have created entirely biological tissue-engineered vascular grafts (TEVGs) using sheets of cell-assembled extracellular matrix (CAM) produced by human fibroblasts in vitro. A large animal TEVG would allow long-term pre-clinical studies in a clinically relevant setting (graft size and allogeneic setting). Therefore, canine, porcine, ovine, and human skin fibroblasts were compared for their ability to form CAM sheets. Serum sourcing greatly influenced CAM production in a species-dependent manner. Ovine cells produced the most homogenous and strongest animal CAM sheets but remained ≈3-fold weaker than human sheets despite variations of serum, ascorbate, insulin, or growth factor supplementations. Key differences in cell growth dynamics, tissue development, and tissue architecture and composition were observed between human and ovine. This study demonstrates critical species-to-species differences in fibroblast behavior and how they pose a challenge when attempting to substitute animal cells for human cells during the development of tissue-engineered constructs that require long-term cultures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.