Evaluating the Effects of Platelet-Rich Plasma and Amniotic Viscous Fluid on Inflammatory Markers in a Human Coculture Model for Osteoarthritis.

Purpose: To assess the anti-inflammatory effects of platelet-rich plasma (PRP) and amniotic viscous fluid using a human coculture system of cartilage and synovial tissue from osteoarthritic patients.

Methods: A coculture system was created using cartilage and synovium from 3 patients undergoing total knee arthroplasty. To induce inflammation, interleukin-1β was added to each coculture. Biologic agents tested included 2 PRP concentrations (PRP and PRP) and 2 different samples of amniotic viscous fluid (Amnion and Flograft). Amnion was also tested with PRP to check for any additive effects. Quantitative polymerase chain reaction was used to measure gene expression of factors involved in osteoarthritis, including disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5), tissue inhibitor of metalloproteinases 1 (TIMP-1), vascular endothelial growth factor (VEGF), aggrecan, type 1 collagen, and nitric oxide, at 0, 24, 48, and 72 hours. A synthetic nonsteroidal medication, Ketorolac, was used for baseline comparison to the biologic agents.

Results: When comparing from time 0, both Amnion and Flograft resulted in significant decreases of ADAMTS-5 and TIMP-1 gene expression in cartilage and synovium for up to 72 hours. Both amniotic preparations increased collagen-1 gene expression in cartilage and decreased VEGF expression in synovium. Amnion was not found to have any effect on nitric oxide concentration at any time point (P > .05), as opposed to both PRP concentrations (P < .05). All biologic agents showed differences in gene expression similar to Ketorolac in ADAMTS-5, TIMP-1, and VEGF expression.

Conclusion: This study found that amniotic fluid had anti-inflammatory effects mostly similar to those of both PRP and PRP; however, no significant additive effects in reducing inflammatory gene expression were found when combining biologic agents.

Clinical Relevance: PRP and amniotic fluid may provide alternative treatment options to delay the progression of the disease without the systemic and intra-articular side effects of corticosteroids.