Repair of articular cartilage defect in non-weight bearing areas using adipose derived stem cells loaded polyglycolic acid mesh

Abstract

The current study was designed to observe chondrogenic differentiation of adipose derived stem cells (ASCs) on fibrous polyglycolic acid (PGA) scaffold stabilized with polylactic acid (PLA), and to further explore the feasibility of using the resulting cell/scaffold constructs to repair full thickness articular cartilage defects in non-weight bearing area in porcine model within a follow-up of 6 months. Autologous ASCs isolated from subcutaneous fat were expanded and seeded on the scaffold to fabricate ASCs/PGA constructs. Chondrogenic differentiation of ASCs in the constructs under chondrogenic induction was monitored with time by measuring the expression of collagen type II (COL II) and glycosaminoglycan (GAG). The constructs after being in vitro induced for 2 weeks were implanted to repair full thickness articular cartilage defects (8 mm in diameter, deep to subchondral bone) in femur trochlea (the experimental group), while scaffold alone was implanted to serve as the control. Histologically, the generated neo-cartilage integrated well with its surrounding normal cartilage and subchondral bone in the defects of experimental group at 3 months post-implantation, whereas only fibrous tissue was filled in the defects of control group. Immunohistochemical and toluidine blue staining confirmed the similar distribution of COL II and GAG in the regenerated cartilage as the normal one. A vivid remolding process with post-operation time was also witnessed in the neo-cartilage as its compressive moduli increased significantly from 50.55% of the normal cartilage at 3 months to 88.05% at 6 months. The successful repair thus substantiates the potentiality of using chondrogenic induced ASCs and PGA/PLA scaffold for cartilage regeneration.