Shear enhances latent TGF-β1 activation. Platelet releasate or serum samples were added to a polystyrene plastic plate and subjected to a shear rate of 1800 s⁻¹ with a rotating cone for the indicated time periods at 37°C. TGF-β1 activity was measured by ELISA (A,B) and by MLEC assay (C,D). Exposure to an increasing shear rate enhances latent TGF-β1 activation. (E) Platelet releasate or (F) serum was subjected to different shear rates for 2 hours in a cone and plate device at 37°C. Active and total TGF-β1 were measured by ELISA. Error bars represent SD.