Comparison of Platelet-Rich Plasma (PRP), Bone Marrow-Derived Mesenchymal Stem Cells‏ and their Combination on the Healing of Achilles tendon in Rabbits

Objectives- The purpose of the study was to observe whether PRP, Mesenchymal Stem Cells (MSCs) and combining them could help make improvements the healing of Achilles tendons in rabbits. Design- Experimental study. Animals-Sixteen male, healthy and mature white New Zealand rabbits. Procedures- The animals were randomiaed into 4 groups: Control, PRP, MSCs with fibrin glue and MSCs + PRP therapy. A 3 mm diameter defect was created in the midsubstance of the medial M. gastrocnemius tendon in all rabbits. After 4 and 8 weeks, animals were euthanized (each time point, 2 rabbits of the each group) and samples were examined in term of histologic scoring with H & E and Masson's Trichrome. Results- Histologic investigations confirmed that all 3 methods of treatment in Achilles tendon defect had suitable reparative effects. Final histologic scoring for control group at 4th week after operation was 4.5 in contrast to treatment groups (PRP =6, MSCs = 5.5 and MSCs + PRP= 8). Final histologic scoring in all 4 groups improved at 8th week after operation (control=6.5, PRP =9.5, MSCs = 8.5 and MSCs + PRP= 14.5). Conclusion and Clinical Relevance- This study indicated that using PRP or MSCs treatment alone and combination of them in injured tendon improved healing process and decreased time of repair. Reparative effect of PRP in tendon defect was better than use of allogenic MSCs treatment. However, the combination of them caused the best results.