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Complement C2 receptor inhibitor trispanning: a novel human complement inhibitory receptor.

Jameel M Inal·Kwok-Min Hui·Sylvie Miot·Sigrun Lange·Marcel Ivan Ramirez·Brigitte Schneider·Gerhard Krueger·Jürg-A Schifferli
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Abstract

The complement system presents a powerful defense against infection and is tightly regulated to prevent damage to self by functionally equivalent soluble and membrane regulators. We describe complement C2 receptor inhibitor trispanning (CRIT), a novel human complement regulatory receptor, expressed on hemopoietic cells and a wide range of tissues throughout the body. CRIT is present in human parasites through horizontal transmission. Serum complement component C2 binds to the N-terminal extracellular domain 1 of CRIT, which, in peptide form, blocks C3 convertase formation and complement-mediated inflammation. Unlike C1 inhibitor, which inhibits the cleavage of C4 and C2, CRIT only blocks C2 cleavage but, in so doing, shares with C1 inhibitor the same functional effect, of preventing classical pathway C3 convertase formation. Ab blockage of cellular CRIT reduces inhibition of cytolysis, indicating that CRIT is a novel complement regulator protecting autologous cells.

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Amino Acid SequenceAnimalsAntigens, HelminthBlood CellsBlotting, SouthernBlotting, WesternCell LineComplement C2Electrophoresis, Polyacrylamide GelEnzyme-Linked Immunosorbent AssayFlow CytometryHelminth ProteinsHumansImmunohistochemistryMolecular Sequence DataReceptors, Cell SurfaceSequence HomologyComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Jameel M Inal, Kwok-Min Hui, Sylvie Miot, Sigrun Lange, Marcel Ivan Ramirez, Brigitte Schneider, Gerhard Krueger, Jürg-A Schifferli. 2005-01-01. Complement C2 receptor inhibitor trispanning: a novel human complement inhibitory receptor.. https://doi.org/10.4049/jimmunol.174.1.356

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