Polymers, scaffolds and bioactive molecules with therapeutic properties in osteochondral pathologies: what’s new?

ABSTRACT

Introduction: Despite clinical efforts, treatments to heal osteochondral lesions remain inefficient and frequently result, long-term, in joint arthroplasty. The complex structure of cartilage tissue, composed of a highly hydrated extracellular matrix (ECM), an avascular nature, and slow cellular turnover, hamper tissue regeneration after trauma or disease. Tissue engineering provides new promising alternatives to current treatments designed to regenerate osteochondral defects.

Area covered: This review describes current and recent strategies of enhancing osteochondral repair through the use of cells, scaffolds, and bioactive molecules. Here, we review the latest (2011–2015) innovative patents in osteochondral regeneration, emphasizing novel strategies for articular cartilage repair. Finally, we present a summary of ongoing clinical trials that are testing innovative engineered products.

Expert opinion: Promising tissue engineering based procedures have emerged as a therapeutic option for the treatment of osteochondral lesions. The development of multilayer scaffolds and the controlled release of bioactive molecules to promote in situ regeneration of both cartilage and bone are some of the latest technologies that intended to improve on the available traditional treatments. To confirm the potential of these novel approaches, long-term evaluation is necessary with special focus on studying the biological and mechanical proprieties of the synthesized tissues.

KEYWORDS:

• Cartilage
• osteochondral pathology
• tissue engineering
• tissue regeneration
• cell therapy
• scaffolds
• growth factors
• biopolymers

Article highlights

• Delivery of cells together with biological composites that include concentrations of hyaluronic acid and collagen improve cell survival and implantation into osteochondral defects. Use of Human placenta membrane preparation and umbilical cord derived products could benefit the regeneration of articular cartilage.

• Scaffolds incorporating nanoparticles could control the release of bioactive molecules to promote in situ regeneration of both cartilage and bone.

• Electrospinning technique and 3D printing are gaining momentum for the development of customized polymer-based scaffold.

• Multilayer scaffolds and combinations of several biomaterials are a better option to create graded structures that resemble the osteochondral interface.

• Novel approaches have been developed to implement implantation of osteochondral grafts directed to adapt to the patient´s lesion.

• The use of scaffolds implantation in one-stage procedure with standard surgical techniques, such as microfracture or drilling, for in situ regeneration of cartilage and bone defects is currently being tested in clinical trials.

• The use mircrofracture combined with chondrogenic factors to direct MSCs differentiation towards chondrocytes could improve the treatment of small defect areas.

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Declaration of interest

This work was supported in part by a grant from the Consejería de Economía, Innovación y Ciencia (Junta de Andalucía, excellence project number CTS-6568). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.