Designing a three-dimensional alginate hydrogel by spraying method for cartilage tissue engineering

Abstract

Cartilage tissue engineering strategies generally result in homogeneous tissue structures with little resemblance to native zonal organization of articular cartilage. The main objective of our work concerns the buildup of complex biomaterials aimed at reconstructing biological tissue with three dimensional cells construction for mimicking cartilage architecture. In this first step, our strategy is based on structure formation by simple and progressive spraying of mixed alginate and chondrocytes at different pressures. We report the first demonstration of spraying effect on chondrocytes inside an alginate hydrogel at short (i) and long terms (ii) and the mechanical behavior of a sprayed hydrogel by biomechanical tests (plane strain compression tests).Our results indicate clearly that during the first days of culture the cells were influenced by the construction method (spraying or molding, control method) with low viability and higher production levels of nitrite. From day 7, the cell behaviors become similar for both methods. Indeed after 28 days of culture, type II collagen was observed, showing the cartilage gene expression, then a similar behavior for all methods. Finally, we conclude that the mechanical performances of sprayed hydrogels was enhanced compared to the controls. We report here, for the first time, that it is possible to spray mixed alginate and chondrocytes with little damage for cells. Therefore, the sprayed hydrogel keeps not only the mechanical properties needed for cells, but also maintains the chondrocyte phenotype to induce cartilage.

Cell-laden hydrogels for osteochondral and cartilage tissue engineering

“…Hydrogels fabricated from natural polymers generally possess good biocompatibility, biodegradability, low immunoresponse, and bioactive motifs encoded in their structures[37–46], and are thus promising biomaterials for OTE and CTE applications. Their derivatives have tunable biodegradability, mechanical properties, and specific biofunctions with chemical modification of functional groups, specific ligands, and macromolecules.…”

“…One unique property of alginate is the ability to be physically crosslinked by divalent cations such as Ca 2+ at room temperature [11, 37, 38, 74–76], which makes it very useful in various biofabrication techniques, including molding, spraying, and 3D bioprinting [77–80]. The resulting physical hydrogels have good biocompatibility, low toxicity, and relatively low cost [36–39, 81–89].…”

In situ spray deposition of cell‐loaded, thermally and chemically gelling hydrogel coatings for tissue regeneration

“…Although there have been many studies to explore the compatibility of airbrush spraying with a number of polymers for production of nanofibers or thin films, there have been only a few studies on the compatibility of airbrush spraying with hydrogels. The possibility of in situ deposition of thermoresponsive hydrogels holds promise for a host of applications ranging from the treatment of burn wounds and ulcers to the regeneration of bone and cartilage tissue defects.…”

Tissue Engineering: From Bench to Bed Side Exemples of Applications

“…However, few investigations have considered the organization of a tissue as a basis for the development of stratified tissues (e.g., cartilage, blood vessels). From this viewpoint, complex 3-D structures of a biotissue could a priori be built layer by layer using different components [9,12]. However, up to now, few methods that can efficiently synthesize stratified structures, including viable specific cells interacting with a biofunctionalized environment have been proposed.…”

“…One example, we recently developed, is the construction of a stratified scaffold seeded with chondrocytes or SC by spraying. The stratified scaffold was constructed of layers of alginate / HA welded by polycation / polyanion (Poly-L-Lysine / HA) [12]. This new method allows the use of a 3D structure, which is important for chondrogenic induction of MSC with no growth factor, but also the construction of a stratified scaffold.…”