Dental pulp stem cells and leukocyte- and platelet-rich fibrin as candidate therapies for articular cartilage and tendon repair

Abstract

Articular cartilage defects and tendon lesions affect millions of patients each year and are associated with a high economic burden. Furthermore, articular cartilage defects often progress into osteoarthritis (OA), a degenerative and inflammatory condition of synovial joints with associated loss of cartilage matrix. Current treatments are unable to provide long-term regeneration of the damaged tissue, stressing the need for alternative therapeutic options including stem cell-based approaches. Human dental pulp stem cells (DPSCs) can differentiate into cartilage-producing cells and secrete numerous growth factors associated with tissue repair. Moreover, leukocyte- and platelet-rich fibrin (L-PRF), an endogenous blood-derived biomaterial, has recently emerged as a promising treatment strategy due to its growth factor content and supportive fibrin matrix. We demonstrated that L-PRF does not enhance the chondrogenic differentiation of DPSCs and BM-MSCs as demonstrated by collagen type 2, aggrecan and glycosaminoglycan (GAG) production. Furthermore, differentiated DPSCs do not produce aggrecan, in contrast to BM-MSCs. Human DPSC- and L-PRF CM displayed a proliferative and a pro-survival effect on chondrocytes in vitro. Additionally, DPSCs were able to migrate towards chondrocytes. Lastly, human DPSCs and PDL-SCs formed tendon-like tissues characterized by the production of collagen and the parallel alignment of cells.