04 Complement
- great for encapsulated bacteria
C3
- Overview of complement
- 3 different pathways, next step always MAC
Alternative Pathway
- destroyed in less than a second if not bound
C3b
- stable c3b creates more of itself via positive loop
Factor H
Lectin Pathway
Classical pathway
- Alternative and MBL part of innate immunity
C1
- IgM: 2 Fc very close together, easy C1 binding
- IgG: ok complement activation
CRP
- binds C polysaccharides of bacteria
C3a C3b
MAC
C5a
Inhibition
PNH
- DAF/CD59 deficiency
- start at RBC lysis
- Free plasma Hgb thrombogenic
- Priapism: sustained prolonged erection
C3 Deficiency
- immune complex: antigen-antibody, usually cleared via complement binding and macrophage
C5-9 deficiency
- not as bad as c3 deficient
Hereditary Angioedema
- c1 inhibitor breaks down bradykinin
- urticaria: histamine, not here
- Epinephrine doesn't work
- ace inhibitor block bradykinin breakdown
C3 Nephritic
Hypocomplementemia
Links to this note
- CH50: classic pathway lysis sheep RBC. Qualitative test, yes or no