Comparative Regenerative Efficacy of PRP Combined with Chondrocytes or Mesenchymal Stem Cells for Intervertebral Disc Regeneration in a Rabbit Model

Intervertebral disc degeneration is a leading cause of chronic back pain, with existing treatments focusing on symptom management rather than true tissue repair. Cellular therapies-such as platelet-rich plasma (PRP), autologous chondrocytes, and mesenchymal stem cells (MSCs)-have emerged as promising strategies for disc regeneration. In this study, fifteen New Zealand white rabbits underwent fluoroscopy-guided needle puncture of the L4-L5 discs and were allocated to receive PRP alone, PRP-chondrocytes, or PRP-MSCs eight weeks later, while the L3-L4 disc served as a healthy internal control. At 16 weeks post-injury, histological scoring revealed significant improvements in annular integrity, cellularity, and matrix composition in all treated groups compared with untreated lesions, with the greatest gains observed in the PRP-chondrocytes arm, intermediate effects with PRP-MSCs, and more modest changes with PRP alone. Complementary RT-qPCR analysis of COL2A1 and COL10A1 expression confirmed a shift toward a more regenerative phenotype, marked by enhanced COL2A1 and reduced COL10A1 levels, which was most pronounced in the PRP-chondrocytes arm. Despite these advances, none of the interventions fully restored the healthy disc architecture, underscoring the complexity of disc repair. These findings support the potential of combining PRP with chondrocytes or MSCs for intervertebral disc regeneration and demonstrate the need for further optimization of cell doses, PRP formulations, and delivery protocols before clinical translation.