Articular cartilage regeneration with a microgel as a support biomaterial. A rabbit knee model.

Articular cartilage has limited regenerative capacity, so focal lesions generate mechanical stress in the joint that induces an aggravation of the damage, which ultimately leads to osteoarthritis. We recently suggested the use of microgels at the site of the cartilage defect, as a support material, to generate a biomechanical environment where pluripotent cells differentiate towards the hyaline cartilage phenotype. Here we propose a chondral regeneration strategy based on subchondral bone injury, and filling the defect site with an agglomerate of two types of microspheres, some rigid made of a biodegradable polyester (40 μm mean diameter), and others with a gel consistency made of platelet-rich plasma obtained from circulating blood (70-110 μm diameter).

Fine-Tuning Regulation of Surface Mobility by Acrylate Copolymers and Its Effect on Cell Adhesion and Differentiation.

Fibronectin (FN) mediates cell-material interactions during events such as tissue repair, and therefore the biomimetic modeling of this protein benefits regeneration. The nature of the interface is crucial in determining cell adhesion, morphology, and differentiation. Poly(ethyl acrylate) (PEA) spontaneously organizes FN into biological nanonetworks, resulting in exceptional bone regeneration in animal models.

A cell-free approach with a supporting biomaterial in the form of dispersed microspheres induces hyaline cartilage formation in a rabbit knee model.

The objective of this study was to test a regenerative medicine strategy for the regeneration of articular cartilage. This approach combines microfracture of the subchondral bone with the implant at the site of the cartilage defect of a supporting biomaterial in the form of microspheres aimed at creating an adequate biomechanical environment for the differentiation of the mesenchymal stem cells that migrate from the bone marrow. The possible inflammatory response to these biomaterials was previously studied by means of the culture of RAW264.

Biocompatibility and Biomechanical Effect of Single Wall Carbon Nanotubes Implanted in the Corneal Stroma: A Proof of Concept Investigation.

Corneal ectatic disorders are characterized by a progressive weakening of the tissue due to biomechanical alterations of the corneal collagen fibers. Carbon nanostructures, mainly carbon nanotubes (CNTs) and graphene, are nanomaterials that offer extraordinary mechanical properties and are used to increase the rigidity of different materials and biomolecules such as collagen fibers. We conducted an experimental investigation where New Zealand rabbits were treated with a composition of CNTs suspended in balanced saline solution which was applied in the corneal tissue.

Time evolution of in vivo articular cartilage repair induced by bone marrow stimulation and scaffold implantation in rabbits.

Purpose: Tissue engineering techniques were used to study cartilage repair over a 12-month period in a rabbit model.

Methods: A full-depth chondral defect along with subchondral bone injury were originated in the knee joint, where a biostable porous scaffold was implanted, synthesized of poly(ethyl acrylate-co-hydroxyethyl acrylate) copolymer. Morphological evolution of cartilage repair was studied 1 and 2 weeks, and 1, 3, and 12 months after implantation by histological techniques.

Biointegration of corneal macroporous membranes based on poly(ethyl acrylate) copolymers in an experimental animal model.

Currently available keratoprosthesis models (nonbiological corneal substitutes) have a less than 75% graft survival rate at 2 years. We aimed at developing a model for keratoprosthesis based on the use of poly(ethyl acrylate) (PEA)-based copolymers, extracellular matrix-protein coating and colonization with adipose-derived mesenchymal stem cells. Human adipose tissue derived mesenchymal stem cells (h-ADASC) colonization efficiency of seven PEA-based copolymers in combination with four extracellular matrix coatings were evaluated in vitro.