Figure 12: Detection of human C3b. Leptospires (108/sample) were treated with 10 μg PLG and 3 U uPA (Plasmin), only with PLG (PLG), or left untreated (UT). The cells were incubated with 15 μg/mL human purified C3b for 20 h at 37°C, and the supernatants were resolved by SDS-PAGE and transferred to membranes. The C3b was detected by specific antibodies followed by ECL reagent development and exposition to X-Ray films. There are indicated the native human C3b alpha chain (105 KDa) and beta-chain (75 KDa), as well as the degradation products (arrows).