Isolation of decay accelerating factor (DAF) by a two-step procedure and determination of its N-terminal sequence.
Decay-accelerating factor (DAF) from human red cell membranes was purified by a two-step procedure involving anion exchange and immunoaffinity chromatography. The DAF preparations were purified to homogeneity as judged by silver staining. In several experiments, the final product yields were approximately 23% of the total DAF present in the initial membrane extracts. The purified DAF retained its ability to inhibit the classical pathway C3-convertase and to reincorporate into cell membranes. An amino-terminal sequence was obtained by gas-phase sequencing. Rabbit antibodies to a synthetic peptide representing part of this sequence reacted with purified reduced membrane DAF by Western blotting and by a solid-phase immunoradiometric assay.
D000595:Amino Acid Sequence; D000906:Antibodies; D000936:Antigen-Antibody Complex; D018958:CD55 Antigens; D002846:Chromatography, Affinity / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D003169:Complement Inactivator Proteins / Q000302:isolation & purification*; D004910:Erythrocyte Membrane / Q000276:immunology; D006801:Humans; D008565:Membrane Proteins / Q000302:isolation & purification*; D011863:Radioimmunoassay / Q000379:methods
D000906:Antibodies; D000936:Antigen-Antibody Complex; D018958:CD55 Antigens; D003169:Complement Inactivator Proteins; D008565:Membrane Proteins