FIGURE 1.

Detection of AP component regulatory protein(s) in PSP using a Q-Sepharose column. A, Q-Sepharose column chromatography. Fractions of 10 ml were collected and the concentration of FH determined as described under “Experimental Procedures.” Absorbance is indicated at 280 nm (filled circles), FH (open circles). B, complement regulatory activity of Q-Sepharose fractions. Q-Sepharose fractions designated A to M and the pass-through fraction (PTF) were dialyzed extensively against Milli-Q water and freeze-dried. The dried-up proteins were dissolved with gelatin veronal buffer. The assay of complement regulatory activity was performed using LPS-coated microtiter plates. Complement activity is presented as percent of the control level, which was measured as the complement activity added to purified FH (250 μg/well). Purified porcine albumin (250 μg/well) was used as a negative control. Each value is the mean ± S.E. from triplicate experiments.