Figure 4.

Effect of plasma preparations (platelet poor, PRGF_2x and PRGF_4x) on secretion of hyaluronic acid (HA) and type I procollagen by skin, synovial and tendon fibroblasts. Box plot representation based on the median (line across the box) and 25th and 75th percentiles. Grey boxes represent the group of experiments performed with the different plasma preparations: platelet‐poor (PPP, light grey) and preparation rich in growth factors (PRGF_2x, dark grey; or PRGF_4x, hatched bars) *P < 0.05 compared to non‐stimulated cells (NS); #P < 0.05 compared to platoelet‐poor preparation; ^§ P < 0.05 compared to PRGF_2x.