TOPICS: liver, acute inflammation, initiation of complement system, spontaneous (alternative) pathway, lectin pathway, classic pathway, C3 convertase, C5 convertase, membrane attack complex (MAC), encapsulated bacteria, C1 inhibitor deficiency, splenectomy, early complement deficiencies, late (terminal) complement deficiencies, paroxysmal nocturnal hemoglobinuria, complement system deficiency, C1, C2, C4, immune complex, systemic lupus erythematosus (SLE), C3, splenectomy, asplenia, IgM, macrophage, phagocytosis, spleen, IgM-mediated complement fixation, hereditary angioedema, bradykinin, C4a, C1 inhibitor concentrate, ACE inhibitors, complement-mediated red blood cell (RBC) lysis, DAF/CD55, MIRL/CD59, GPI anchor proteins, PIGA gene, haptoglobin, anemia, opsonization