TGFβ1 delivery in paracrine manner leads to dose-dependent myofibroblast differentiation. Myofibroblast differentiation correlates with TGFβ1 loading concentration of µ-beads and thereby with delivered TGFβ1 concentration. Myofibroblast differentiation was quantified by Smad2/3 nucleus (nuclear Smad2/3+) and fibrillar αSMA (αSMA+) staining. Fraction of Smad2/3+ and αSMA+ cells were normalized to positive control (10 ng/ml TGFβ1 systemic) as 1 and negative control (no additional TGFβ1) as 0. Data are presented as mean ± standard deviation. Experiments were done in triplicate, each experiment with fibroblasts from a different donor. For each condition, about 100 cells were investigated.