Fig. 6
ARMS2 anchors the human complement activator properdin on cell surfaces. a Co-localization (yellow) of ARMS2 (green) and purified properdin from NHS (red) or (b) properdin from supernatant of human neutrophils (red) on CHO-K1 cells by laser scanning microscopy. Nuclei are stained with DAPI (blue). Scale bar 5 μm. Representative data from two independent experiments are shown. c Recruitment of purified (left profile) and endogenous properdin to ARMS2 on CHO-K1 cells. ARMS2 was attached to CHO-K1 cells and incubated for 1 h with purified properdin or in alternative pathway active (Mg2+ EGTA), complement inactive (EDTA), or properdin deficient HS as indicated. Properdin binding was determined by flow cytometry. Representative binding profiles of two independent experiments are shown. Background binding of the antibody to the cells is marked (co)