title: Elongation factor-1alpha as a homologous complement activator of Jurkat cells.
abstract: Although increasing evidence exist suggesting that apoptotic cells activate homologous complement, the homologous complement activators are only poorly characterized. We found that cell lysate of Jurkat cells contained a homologous complement activator of 50 kDa. Digestion of the 50 kDa activator with lysylendopeptidase yielded peptide fragments, with sequences identical to those of EF-1alpha. The 50 kDa activator was removed by immunoadsorption with anti-EF-1alpha, suggesting that the 50 kDa activator is EF-1alpha. The homologous complement activation did not proceed with EGTA-serum. In addition, C4b, a fragment produced by activation of the classical or lectin pathways was found to bind with EF-1alpha. These results suggest that EF-1alpha activates the homologous complement through the classical or lectin pathway.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Aoki
authors.forename: F
authors.initials: F
authors.lastname: Takizawa
authors.forename: S
authors.initials: S
authors.lastname: Tsuji
authors.forename: S
authors.initials: S
authors.lastname: Nagasawa
mesh_terms: D000595:Amino Acid Sequence; D017209:Apoptosis; D015153:Blotting, Western; D003167:Complement Activation; D015935:Complement C4b / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005434:Flow Cytometry; D006801:Humans; D019169:Jurkat Cells; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020648:Peptide Elongation Factor 1 / Q000737:chemistry / Q000378:metabolism*; D020539:Sequence Analysis, Protein
chemical_list: D020648:Peptide Elongation Factor 1; D015935:Complement C4b