Cellules souches et biomatériaux injectables pour la médecine régénératrice du cartilage : le consortium « chondrograft »

Abstract

Articular cartilage is a non innerved, nonvascularized and poorly cellularized connective tissue that is frequently damaged as a result of trauma or age-linked degenerative diseases. It hardly heals spontaneously and its alterations often lead to further extracellular matrix degradation and ultimately, to the loss of joint function. Past decades, many therapeutic approaches have been developed to improve the poor intrinsic self-repair properties of cartilage. Unfortunately, these techniques have not proved really satisfying. In this context, the regeneration of a functional cartilage through tissue engineering and regenerative medicine has recently been contemplated. In particular, the transplantation of autologous reparative cells using a synthetic biomaterial appears promising. We have thus developed and patented a biocompatible self-setting cellulose hydrogel that can be used as an injectable scaffold for cell-based regenerative medicine. Our studies associate this hydrogel with adult mesenchymal stem cells derived from adipose tissue, as a source of reparative cells for cartilage tissue engineering. In a first set of experiments, we have determined the optimal culture conditions required to induce the controlled chondrogenic commitment of stem cells (morphogens, hypoxia, three-dimensional environments…). The preclinical potential of hybrid constructs associating cells and hydrogel has then been assessed with success in animals (mouse, rabbit). Today, trauma and degenerative pathologies of joint tissues remain a major challenge for clinicians and cartilage engineers. Establishing the proof of concept of hydrogel-associated stem cells-based regenerative medicine could help us open new therapeutic windows in the treatment of joint disorders.