The role of Alk-1 and Alk-5 in the mechanosensing of chondrocytes.

We aim to demonstrate the role of Alk receptors in the response of hydrogel expansion. Chondrocytes from rat knees were cultured onto plastic and hydrogel surfaces. Alk-1 and Alk-5 were overexpressed or silenced and the effects on cells during expansion were tested and confirmed using peptide inhibitors for TGFβ.

Improved Chondrogenic Capacity of Collagen Hydrogel-Expanded Chondrocytes: In Vitro and in Vivo Analyses.

Background: The use of autologous chondrocytes in cartilage repair is limited because of loss of the cartilage phenotype during expansion. The mechanosensing capacity of chondrocytes suggests evaluating the use of soft substrates for in vitro expansion. Our aim was to test the expansion of chondrocytes on collagen hydrogels to improve their capacity for chondrogenesis after a number of passages.

Response of sheep chondrocytes to changes in substrate stiffness from 2 to 20 Pa: effect of cell passaging.

Aim: The influence of culture substrate stiffness (in the kPa range) on chondrocyte behavior has been described. Here we describe the response to variations in substrate stiffness in a soft range (2-20 Pa), as it may play a role in understanding cartilage physiopathology.

Methods: We developed a system for cell culture in substrates with different elastic moduli using collagen hydrogels and evaluated chondrocytes after 2, 4, and 7 days in monolayer and three-dimensional (3D) cultures.

Culture of human bone marrow-derived mesenchymal stem cells on of poly(L-lactic acid) scaffolds: potential application for the tissue engineering of cartilage.

Purpose: Due to the attractive properties of poly(L-lactic acid) (PLLA) for tissue engineering, the aim was to determine the growth and differentiation capacity of mesenchymal stromal cells (MSCs) in PLLA scaffolds and their potential use in the treatment of cartilage diseases.

Methods: MSCs were cultured in PLLA films and thin porous membranes to study adherence and proliferation. Permeability and porosity were determined for the different scaffolds employed.