X-Nico

3 unusual facts about Alternative complement pathway


Alternative complement pathway

Factor I requires a C3b-binding protein cofactor such as complement factor H, CR1, or Membrane Cofactor of Proteolysis (MCP or CD46)

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CFHR5 (Complement Factor H-Related protein 5) is able to bind to act as a cofactor for factor I, has decay accelerating activity and is able to bind preferentially to C3b at host surfaces.

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This change in shape allows the binding of plasma protein Factor B, which allows Factor D to cleave Factor B into Ba and Bb.



see also