A bFGF-releasing silk/PLGA-based biohybrid scaffold for ligament/tendon tissue engineering using mesenchymal progenitor cells

Tendon Healing with Growth Factors

“…While reducing expression of collagen I and III in the first week (Thomopoulos et al, 2010), it increased both after two weeks (Sahoo et al, 2010), again suggesting a prolonged phase of proliferation, associated with a higher repair potential in a normally bradytrophic tissue. Extracellular matrix changes associated with bFGF are an increase of lubricants and matrix metalloproteases during the first week, supposedly creating the space needed for the additional tenoblasts and tenocytes (Thomopoulos et al, 2010).…”

The past, present and future in scaffold-based tendon treatments

“…Given there is currently no sufficiently effective pharmaceutical-based therapy, the use of more potent biological molecules was proposed as an alternative strategy. increases revascularisation of repairing tendon tissue, improving overall healing [169]; plateletderived growth factor (PDGF) has beneficial effects on the functional repair of tendon tissue in the canine model, increasing tendon glide, but not mechanical properties, over a 42 day period [170]; basic fibroblast growth factor (bFGF) stimulates both MSC proliferation and differentiation towards tenogenic lineage, leading to increased expression of tendon specific ECM proteins and increased collagen production from cells [171]; bone morphogenic protein 12 (BMP-12), also referred to as growth differentiation factor 7 (GDF-7) induces both in vitro and in vivo tenogenesis of MSCs in both human and equine cells [172][173][174]; BMP-13 (GDF-6) induces an increase in the expression of tendon specific proteins in rat MSCs along with increasing the characteristic wave like pattern found in tendon histological samples after 14 days implantation in a rat Achilles defect model [175]; BMP-14 (GDF-5) reduces adhesion formation between tendons and surrounding tissues, improving overall function and recovery [176]; early growth response protein 1 (EGR1) directs tendon differentiation in rat MSCs and improve tendon healing in a rat Achilles tendon injury model [177]; and transforming growth factor-β (TGF-β) is highly influential in the recruitment and maintenance of TC progenitor cells during injury [178]. While these growth factors have demonstrated efficacy, as assessed by increased cellular migration, matrix production and matrix mechanical properties over a short period of time (up to around 8 weeks), little difference has been documented in long term tissue integration, matrix composition and overall tissue strength over control groups [177,178].…”

Substrate topography: A valuable in vitro tool, but a clinical red herring for in vivo tenogenesis

“…electro-spinning [26][27][28][29][30][31], fibre extrusion [32][33][34][35], isoelectric focusing [36,37] and imprinting [38][39][40]) have been at the forefront of scientific and technological research and innovation to recapitulate native tendon extracellular matrix (ECM) supramolecular assemblies. Although fibrous constructs (e.g.…”