Objective: To investigate the ability of platelet-rich plasma(PRP) combined with cells and artificial bone in accelerating the repair of bone defect.
Methods: The marrow stromal stem cells (MSCs) of rabbit were cultured and induced into the osteoblast-like cells in vitro. PRP was produced with low-density twice centrifugations. Forty-eight New Zealand rabbits were made 1.2 cm bilateral radius defect models and divided into 4 groups averagely at random: group A (left:PRP/MSCs/beta-tricalcium phosphate (beta-TCP), right: MSCs/beta-TCP), group B (left:auto-radius, right: PRP/MSCs/beta-TCP); group C (left:auto-radius, right: MSCs/beta-TCP), and group D (left:PRP/beta-TCP; right:beta-TCP). At 2, 6 and 12 weeks after operation, the repair of bone defect was evaluated by the general observation, histology, biomechanics and histomorphology.
Results: There was a stable platelet concentration in PRP and it was about 5.45+/-0. 23 times of whole blood. In the aspect of bone bridge and conture of the defects, at 2 and 6 weeks, PRP/MSCs/ beta-TCP and MSCs/beta-TCP displayed a similar outcome and were less than auto in general sample and X-ray; at 12 weeks, PRP/MSCs/beta-TCP was similar to auto-radius and better than MSCs/beta-TCP. in the aspect of quantity and quality of bone formation, histology showed that PRP/MSCs/beta-TCP and auto-radius were better than MSCs/beta-TCP (P < 0.05), and there was no significant difference between PRP/MSCs/beta-TCP and auto-radius (P>0.05). At 2 and 6 weeks, there was no significant difference between PRP/beta-TCP and beta-TCP (P>0.05). At 12 weeks, PRP/beta-TCP was better than beta-TCP (P<0.05). In the aspect of intensity of bone formation, at 6 and 12 weeks, PRP/MSCs/beta-TCP and auto-radius were better than MSCs/beta-TCP (P<0.05). At 6 weeks, auto-radius was better than PRP/MSCs/beta-TCP (P < 0.05). At 12 weeks, there was no significant difference between PRP/MSCs/beta-TCP and auto (P>0.05). PRP/TCP and beta-TCP had no significant difference at 12 weeks (P> 0.05).
Conclusion: PRP/MSCs/beta-TCP demonstrated excellent ability of forming bone in experiment. PRP was most likely to accelerate the repair of bone defect through increasing the activity of proliferation and differentiation of MSCs and osteoblasts.