An In Vitro Evaluation of the Anti-Inflammatory Effects of Platelet-Rich Plasma, Ketorolac, and Methylprednisolone

Purpose: The purpose of this study was to quantify the extent of the anti-inflammatory effect of platelet-rich plasma (PRP) in a controlled in vitro environment. Methods: Through the stimulation of human umbilical vein endothelial cells with inflammatory cytokines (tumor necrosis factor alpha and interferon gamma), cell adhesion molecule expression (E-selectin, vascular cell adhesion molecule, and human leukocyte antigen DR) and PRP's anti-inflammatory effect can be measured. PRP was produced from 3 individuals using a single-spin (PRPLP) process. Treatment groups include negative (unstimulated) controls, positive (stimulated) controls, ketorolac tromethamine, methylprednisolone, PRP, ketorolac-PRP, and methylprednisolone-PRP. A fluorescence assay of the cellular inflammation markers was measured by the BioTek Synergy HT plate reader (BioTek Instruments, Winooski, VT) at 0, 1, 2, and 5 days. Results: At days 2 and 5, methylprednisolone treatment showed a 2.1- to 5.8-fold reduction (P < .05) in inflammation markers over PRP. In addition, PRP and ketorolac showed a 1.4- to 2.5-fold reduction (P < .05) in cellular inflammation markers over the control. There was no statistically significant difference between ketorolac and PRP. Conclusions: Although PRP and ketorolac reduced cellular inflammation markers (E-selectin, vascular cell adhesion molecule, and human leukocyte antigen DR) compared with control, neither caused as great a reduction as methylprednisolone. Clinical Relevance: Although PRP and ketorolac did not produce as significant a reduction in cellular inflammation markers as methylprednisolone, they reduced cellular inflammation compared with the control. These agents may have clinical application as injectable anti-inflammatory medications.