Last reviewed dd mmm yyyy. Last edited dd mmm yyyy
Aggregated IgA, particulate polysaccharides and endotoxin lipopolysaccharides, may bypass the classical activation of the complement cascade by activating C3 directly. This results in more ready activation of the alternative cascade by Gram negative than Gram positive bacteria.
C3 is cleaved to C3a and C3b. C3b binds with co-factors B, D and magnesium ions in the target cell membrane to form an active enzyme which cleaves further C3. Properdin stabilises this step.
C3b, as with the classical pathway, also cleaves C5 to trigger the formation of the membrane attack complex.
Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.