Fig. 3.

Mannan binding lectin-associated serine protease (MASP-1) activates human hepatic stellate cells (HSCs) cultured on Matrigel™-coated plates. Human HSCs were cultured in Matrigel™ thin gel as described treated with: thrombin at a dose of 30 mU/ml (a); purified MASP-1 cleaved with enterokinase at a dose of 2·5–3·5 μg/ml [with an equivalent capacity to cleave Boc-Val-Pro-Arg-aminomethylcoumarin (VPR-AMC) as 30 mU/ml of thrombin] (b); transforming growth factor (TGF)-β at a dose of 5 ng/ml (c). HSC treated with an equivalent dose of MASP-1 zymogen which had not been cleaved with 0·2% enterokinase (d) and HSCs cultured on Matrigel™ exposed to 0·2% enterokinase alone (e) were used as controls. (a–c) The ‘myofibroblast’ morphology typical of fully activated HSCs, whereas HSC shown in (d,e) remain in the quiescent state. Magnification was selected to best illustrate the key features: (a,b,c) ×200 magnification and (d,e) ×100 magnification.