Comparison of the efficacy of autologous Lp-PRP and Lr-PRP for treating intervertebral disc degeneration: in vitro and in vivo study.

Background: Intervertebral disc degeneration (IDD) was the most common cause of low back pain. Platelet rich plasma (PRP) has the potential to repair IDD, however, there is still no conclusion on whether Leukocyte-poor platelet rich plasma (Lp-PRP) or Leukocyte-rich platelet rich plasma (Lr-PRP) is better for the treatment of IDD.

Methods: First, we conducted an in vitro study to compare the effects of autologous Lp-PRP and Lr-PRP on human degenerated nucleus pulposus (NP) cells. Then we verified the in vivo effects of autologous Lp-PRP and Lr-PRP in treating disc degeneration through a rabbit IDD model.

Results: The in vitro study showed both autologous Lp-PRP and Lr-PRP can promote the cell proliferation, the synthesis of COL II and Aggrecan of human degenerated NP cells, while Lp-PRP are better than Lr-PRP (P<0.05). In addition, only Lp-PRP can inhibit the apoptosis of human degenerated NP cells (P<0.05), whereas Lr-PRP activates the catabolism on the contrary (P<0.05). Further, the in vivo study through the rabbit IDD model verified that autologous Lp-PRP has better effects than autologous Lr-PRP in repairing IDD according to X-ray, MRI, histological, and immunohistochemical assessment (P<0.05, respectively). And the caspase-3 IHC results also showed that only autologous Lp-PRP treatment could inhibit apoptosis of NP cells in the rabbit IDD model (P<0.05).

Conclusion: Combining in vivo and in vitro studies, the present study confirmed that autologous Lp-PRP has a better effect than autologous Lr-PRP in repairing IDD, which may be due to the inflammatory factors (TNFα, IL-1β, etc.) in Lr-PRP antagonizing part of the repair effects and promoting the catabolism additionally. Therefore, our findings suggest that Lp-PRP may provide better results than Lr-PRP for treating IDD. Further randomized clinical trials will provide evidence to guide practice.