Harnessing Human Decellularized Blood Vessel Matrices and Cellular Construct Implants to Promote Bone Healing in an Ex Vivo Organotypic Bone Defect Model

Abstract

Decellularized matrices offer a beneficial substitute for biomimetic scaffolds in tissue engineering. The current study examines the potential of decellularized placental vessel sleeves (PVS) as a periosteal protective sleeve to enhance bone regeneration in embryonic day 18 chick femurs contained within the PVS and cultured organotypically over a 10 day period. The femurs are inserted into decellularized biocompatibility-tested PVS and maintained in an organotypic culture for a period of 10 days. In femurs containing decellularized PVS, a significant increase in bone volume (p < 0.001) is evident, demonstrated by microcomputed tomography (µCT) compared to femurs without PVS. Histological and immunohistological analyses reveal extensive integration of decellularized PVS with the bone periosteum, and enhanced conservation of bone architecture within the PVS. In addition, the expressions of hypoxia inducible factor-1 alpha (HIF-1α), type II collagen (COL-II), and proteoglycans are observed, indicating a possible repair mechanism via a cartilaginous stage of the bone tissue within the sleeve. The use of decellularized matrices like PVS offers a promising therapeutic strategy in surgical tissue replacement, promoting biocompatibility and architecture of the tissue as well as a factor-rich niche environment with negligible immunogenicity.

Evolving applications of the egg: chorioallantoic membrane assay and ex vivo organotypic culture of materials for bone tissue engineering

“…157 µCT allows quantification of femur length, bone volume, trabecular number, thickness and separation to compare materials with the controls 145,153 (Figure 7). Similar to the CAM assay tissue samples, histological stains used include Sirius red to demarcate collagen formation, Alcian blue to illustrate proteoglycans or Goldner's trichrome for calcified, mature and immature bone matrix 148 (Figure 11). Von Kossa staining illustrates areas of mineralisation within the femur or defect, while specific histological stains such as those for collagen type I/II or surface marker selected cells (e.g., Stro-1+) can be used.…”

“…This technique also permits immunohistochemistry post tomography. µCT is a sensitive method to assess bone formation or remodelling and has been used to calculate the overall bone gain/loss of human femoral bone cores 50 , 51 ( Figure 3 ), chick femurs 145 – 148 ( Figure 7 ) and could be used to assess bone formation within scaffolds on the CAM. 149 …”

“… Source : Figure adapted and reproduced from Inglis et al. 146 , 148 with permission from FASEB J and Advanced Healthcare Materials. …”

“…(c) A cell pellet is cultured (d) for implantation into defect. Source: Figure adapted and reproduced from Inglis et al146,148 with permission from FASEB J and Advanced Healthcare Materials.…”

H₂O₂ Damages the Stemness of Rat Bone Marrow-Derived Mesenchymal Stem Cells: Developing a “Stemness Loss” Model

“…These injuries often lead not only to lifelong disability, but also to a physical and economic burden for the patient’s family and for society [1]. Although in past decades stem cell transplantation has experienced great advances and has been used for muscle regeneration [2,3], osteoporosis [4,5], wound healing [6,7] and blood regeneration [8,9], there are still many problems with this therapeutic approach, including poor survival and limited proliferation of transplanted cells [10]. Oxidative stress plays an important, negative role in the process of stem cell transplantation [11–13].…”