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Normal platelet function in platelet concentrates requires non-platelet cells: a comparative in vitro evaluation of leucocyte-rich (type 1a) and leucocyte-poor (type 3b) platelet concentrates
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  • Published on:
    Leucocyte Rich and Poor Platelet Concentrates and Tenocyte Proliferation
    • Marko Bodor, MD, Interventional Spine and Sports Medicine Physician University of California San Francisco, University of California Davis, Bodor Clinic
    • Other Contributors:
      • Ryan Dregalla, PhD, Regenerative Science Research & Development
      • Yvette Uribe, BA, Clinical Researcher

    We read with interest the article by Parrish et al, “Normal platelet function in platelet concentrates requires non-platelet cells: a comparative in vitro evaluation of leucocyte-rich (type 1a) and leucocyte-poor (type 3b) platelet concentrates.”(1)

    Parrish et al define PRP as a preparation with a platelet concentration of at least 5x over baseline, yet the LP-PRP they prepared (Arthrex Autologous Conditioned Plasma) was significantly lower at 2x over baseline, while the LR-PRP (Mitek Sports Medicine PEAK PRP) was significantly higher at 8x over baseline. We might reasonably expect that the ratio of growth factors between their LR-PRP and their LP-PRP to be approximately 8x/2x or 4:1, and this was indeed the case as seen in their Figure 4.

    Subsequently, the authors grew tenocytes (tendon cells) exposed to serum derived from LR-PRP and LP-PRP preparations. Given that their LR-PRP was approximately 4 times richer in growth factors than their LP-PRP, we might reasonably expect that the 2.5% solution of serum derived from their LR-PRP have approximately the same effect as the 10% solution of serum derived from their LP-PRP. However, their 10% LP-PRP solution actually resulted in higher growth of tenocytes (2656 light units) than their 2.5% LR-PRP solution (1001 light units), as seen in their Table 5, but not discussed by the authors. The fact that their 10% LR-PRP-derived serum caused tenocytes to grow to confluence while their 10% LP-PRP-derived serum did...

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    Conflict of Interest:
    None declared.