Effect of potentiated cryopreserved mesenchymal stem cells in intervertebral disc repair

Abstract

The aim of the study was to investigate the effect of cryopreserved mesenchymal stem cells (CrMSCs) from different tissue (bone marrow, adipose tissue, cartilage) potentiated with some growth and differentiation factors (TGFβ and bFGF) on intervertebral disc (IVD) cartilage repair using compression model of degenerative damage. In the group with self-healing histological changes in IVD cartilage tissue were pronounced. Administration of untreated CrMSCs (regardless of their origin) regenerated IVD structure up to a moderate degree on the 45th day. After therapy with TGFβ-potentiated cells, the histological structure of the disc remained similar to untreated CrMSC influence, which according to the integrated semi-quantitative scale corresponded to moderate degenerative changes. Whereas, the administration of bFGF-potentiated cells contributed to the restoration of the disc structure up to a mild degree of histological damages. In the latter case, there was an increase in cellularity of the fibrous ring, regeneration of cracks and gaps, and restoration of collagen febrile structure in annulus fibrosus on the 45th day after therapy. At the same time, the average cell density of fibrous rings increased by 1.35, 1.50, and 1.39 times and IVD height grew by 1.33, 1.36, and 1.37 times for bone marrow-, adipose- and cartilage-derived CrMSC of potentiated by bFGF respectively compared to untreated analog. Thus, administration of CrMSCs from all studied sources activates regenerative processes in degenerated intervertebral discs of rats, the rate of which increases using of bFGF-potentiated cells.