Tissue engineered bone grafts based on biomimetic nanocomposite PLGA/amorphous calcium phosphate scaffold and human adipose-derived stem cells

Abstract

For tissue engineering of critical size bone grafts, nanocomposites are getting more and more attractive due to their controllable physical and biological properties. We report in vitro and in vivo behaviour of an electrospun nanocomposite based on poly-lactic-co-glycolic acid and amorphous calcium phosphate nanoparticles (PLGA/a-CaP) seeded with human adipose-derived stem cells (ASC) compared to PLGA. Major findings were that cell attachment, three-dimensional ingrowth and proliferation were very good on both materials. Cell morphology changed from a spindle-shaped fibroblast-like form to a more roundish type when ASC were seeded on PLGA, while they retained their morphology on PLGA/aCaP. Moreover, we found ASC differentiation to a phenotype committed towards osteogenesis when a-CaP nanoparticles were suspended in normal culture medium without any osteogenic supplements, which renders a-CaP nanoparticles an interesting osteoinductive component for the synthesis of other nanocomposites than PLGA/a-CaP. Finally, electrospun PLGA/a-CaP scaffold architecture is suitable for a rapid and homogenous vascularisation confirmed by a complete penetration by avian vessels from the chick chorioallantoic membrane (CAM) within one week.

Adipose-Derived Stem Cells in Tissue Regeneration: A Review

“…Specifically, the osteogenic, adipogenic, and chondrogenic potentials of ASCs were confirmed using a combination of immunofluorescence, PCR analysis and functional assay for bone, cartilage, and fat formation. In support of their work, the tri-lineage mesodermal potential of human ASCs has since been confirmed in a series of in vitro articles using a variety of induction conditions (Table 2), including dexamethasone [38,39], (VD3) [40], hypoxia [41,42], numerous growth factors and hormones [43][44][45][46][47][48], mechanical stress [49][50][51], and even scaffolding materials such as akermanite [52] and amorphous calcium phosphate nanoparticles [53]. Osteogenesis by human ASCs has also been reported under 3D culture on a wide variety of scaffolds such as collagen [54], PLGA [55,56], tricalcium phosphate substrates [57], sintered matrices [58], multiwalled carbon nanotubes [59], silk sponges [60], bioactive glass [61], and polycaprolactone [62].…”

The role of pleiotrophin in bone repair

“…Bone repair is a complex process of biological events regulated by specific cells, the extracellular matrix, distinct growth factors and a variety of hormones [92][93][94][95][96][97][98][99][100]. Despite the increased intrinsic capacity of bone to restore fracture healing without scar formation, non-union may still occur in 5-10% of the cases [101].…”

Synthesis and characterization of nanosized calcium phosphates by flame spray pyrolysis, and their effect on osteogenic differentiation of stem cells

“…3 9 10 5 urine-derived cells were seeded per well in 24-well plates in osteogenic medium. Amorphous CaP nanoparticles in DMEM were added to each well at different final concentrations of particles of 5, 10, 25, and 50 lg/ml, respectively (Buschmann et al 2012). Urine-derived stem cell culture in osteogenic medium without nanoparticles served as control.…”