This pathway can be activated by mannan-binding lectins or antigen-antibody complexes.
The aberrant activation of this pathway causes paroxysmal nocturnal hemoglobinuria. Cleavage of a thioester bond causes basal activation of this pathway, a phenomenon termed tickover. People with deficiencies in this pathway are susceptible to repeated meningococcus infections. This pathway can be activated by mannan-binding lectins or antigen-antibody complexes. In this pathway, the membrane attack complex is assembled by C5 through C9 after the formation of C3 and C5 convertase, and this pathway is responsible for destroying bacteria independent of cell-mediated immunity. For 10 points, name this cascade, a part of the innate immune system named for the fact that it adds to the defense provided by the adaptive immune system.
The aberrant activation of this pathway causes paroxysmal nocturnal hemoglobinuria.
complement system [or complement cascade; or complement pathway]