Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis

Abstract

Osteoarthritis, which typically arises from aging, traumatic injury, or obesity, is the most common form of arthritis, which usually leads to malfunction of the joints and requires medical interventions due to the poor self-healing capacity of articular cartilage. However, currently used medical treatment modalities have reported, at least in part, disappointing and frustrating results for patients with osteoarthritis. Recent progress in the design and fabrication of tissue-engineered microscale/nanoscale platforms, which arises from the convergence of stem cell research and nanotechnology methods, has shown promising results in the administration of new and efficient options for treating osteochondral lesions. This paper presents an overview of the recent advances in osteochondral tissue engineering resulting from the application of micro- and nanotechnology approaches in the structure of biomaterials, including biological and microscale/nanoscale topographical cues, microspheres, nanoparticles, nanofibers, and nanotubes.

Keywords: biological cues; cartilage regeneration; micro/nanotopographical cues; nanotechnology; osteoarthritis; regenerative medicine.

Figure 1

A schematic representation of the issues covered in this review.

Figure 2

Simplified graphical representation of a cross section of articular cartilage and its associated molecular components. Articular cartilage is normally divided into four distinct regions (the superficial, middle, deep, and calcified zones) visually characterized by the orientation of the collagen fibrils and chondrocyte morphology.

Figure 3

(Top) SEM images of electrospun nanofibers, representing the soft group (35% modified MeHA) and the stiff group (100% modified MeHA). (Bottom) Gene expression analysis of chondrogenic markers of hMSCs seeded on these scaffolds. RGD peptides in different concentrations were also used to enhance scaffold adhesivity. Figure 3 was reprinted from [8], Biomaterials, vol. 34, by I. L. Kim; S. Khetan; B. M. Baker; C. S. Chen; J. A. Burdick, “Fibrous hyaluronic acid hydrogels that direct MSC chondrogenesis through mechanical and adhesive cues”, pages 5571–5580, Copyright (2013), with permission from Elsevier. This content is not subject to CC BY 4.0.

Figure 4

Schematic representation of GelMA-coated CNTs embedded in gelatin hydrogel for the preparation of the engineered cardiac tissue. Confocal images revealed that cardiomyocytes cultured on 1 mg/mL CNT-GelMA hydrogel had a more uniform cell distribution relative to cells cultured on control GelMA hydrogel. Schematic representation of a tubular actuator and its beating direction (red arrow) in addition to an optical image of a sample. Figure 4 was reprinted with permission from [132], Copyright (2013) American Chemical Society. This content is not subject to CC BY 4.0.