The induction of bone formation by smart biphasic hydroxyapatite tricalcium phosphate biomimetic matrices in the non‐human primate Papio ursinus

Abstract

Long-term studies in the non-human primate Chacma baboon Papio ursinus were set to investigate the induction of bone formation by biphasic hydroxyapatite/p-tricalcium phosphate (HA/β-TCP) biomimetic matrices. HA/β-TCP biomimetic matrices in a pre-sinter ratio (wt%) of 40/60 and 20/80, respectively, were sintered and implanted in the rectus abdominis and in calvarial defects of four adult baboons. The post-sinter phase content ratios were 19/81 and 4/96, respectively. Morphological analyses on day 90 and 365 showed significant induction of bone formation within concavities of the biomimetic matrices with substantial bone formation by induction and resorption/dissolution of the implanted matrices. One year after implantation in calvarial defects, 4/96 biphasic biomimetic constructs showed prominent induction of bone formation with significant dissolution of the implanted scaffolds. The implanted smart biomimetic matrices induce de novo bone formation even in the absence of exogenously applied osteogenic proteins of the transforming growth factor-β(TGF-β) superfamily. The induction of bone formation biomimetizes the remodelling cycle of the cortico-cancellous bone of primates whereby resorption lacunae, pits and concavities cut by osteoclastogenesis are regulators of bone formation by induction. The concavities assembled in HA/β-TCP biomimetic bioceramics are endowed with multifunctional pleiotropic self-assembly capacities initiating and promoting angiogenesis and bone formation by induction. Resident mesenchymal cells differentiate into osteoblastic cell lines expressing, secreting and embedding osteogenic soluble molecular signals of the TGF-β superfamily within the concavities of the biomimetic matrices initiating bone formation as a secondary response.

Influence of surface microstructure and chemistry on osteoinduction and osteoclastogenesis by biphasic calcium phosphate discs

“…However, this in vitro characterisation is limited in light of the physico-chemical complexity of body fluid in vivo, including supersaturated Ca 2+ /P i levels as well as blood serum (Garnett and Dieppe, 1990). Other theories on osteoinduction speculate that material degradation by osteoclast resorption or macrophage phagocytosis may independently speed the dissolution/precipitation of a bioactive carbonate apatite layer (LeGeros, 1993), establish an instructive geometric template for de novo bone formation in resorption lacunae along with increased local Ca 2+ concentrations (Klar et al, 2013;Ripamonti et al, 2008;Wilkinson et al, 2011), or liberate crystalline nano-/microparticulate and a subsequent osteogenic cytokine cascade Malard et al, 1999;Velard et al, 2013). However, in the present study neither characteristic osteoclast resorption lacunae nor degraded BCP particulate were apparent in the histology.…”

In vitro osteoclast-like and osteoblast cells’ response to electrospun calcium phosphate biphasic candidate scaffolds for bone tissue engineering

“…Bone-forming osteoblast cells are then formed from these stimulated stem cells. Many studies have aimed to provide a more detailed understanding of the osteoinduction potential of HA and many of them have showed osteoinduction in various hosts including baboons [24][25][26][27][28].…”

Introductory Chapter: The Testament of Hydroxyapatite: New Prospects in Regenerative Medicinal Treatments

“…Far ahead, the development would change to the responsive nature of the material, also for the growth of bone the reactive material pretends as a conductive scafold [7]. In recent trend, developing fabrication technology with the dawn of recognizing of regenerative medicinal growth in the ield of nanotechnology and have transformed the appearance of bioceramics to a dissimilar facet [9][10][11][12][13][14].…”