Effect of Ecb on proteolytic cleavage of C3b by sCR1 and factor I.

<p>Proteolysis of ¹²⁵I-C3b was analyzed by the intensity of the α’-chain in autoradiography. The intensity in the absence of sCR1 (negative control, black bar), was set to 100% and cleavage in the presence of sCR1 but absence of Ecb was used as a positive control (dark grey bar). The lanes in the upper panel shows the α’-chain in the SDS-page gel. The x-axis shows the presence (+) or absence (-) of the protein and the concentrations (0.002–2.2 μM) of Ecb in the sample.