Analysis of CFHR proteins by 2-DE. (A) Western blots obtained after monodimensional (1DE) or 2-dimensional (2DE) electrophoresis of the heparin-sepharose eluate corresponding to control person C1, showing the Normal CFHR pattern. A single antibody solution containing equivalent amounts of the individual αCFHR1, αCFHR3/4, and αCFHR5 antibody preparations was used. The position and size (in kDa) of molecular weight markers is also indicated. (B) Two-dimensional analysis of CFHR1/CFHL1 and CFHR3/CFHR4B isoforms in control sample C1 and in 3 patients with aHUS showing the CFHR patterns DefR1R3, DefR1, or DefR3. CFHR4B isoforms are surrounded by dotted circles. Arrows indicate CFHL1 isoforms. The theoretical isoelectric points calculated with Compute pI/molecular weight program at ExPASy server (http://ca.expasy.org/tools/pi_tool.html) were CFH (6.12), CFHL1 (6.77), CFHR1 (7.53), CFHR3 (7.79), CFHR4A (4.85), CFHR4B (5.16), and CFHR5 (6.87).