Complement Flashcards
(20 cards)
what activates the classic pathway
antigen-Ab complexes (IgM or IgG)= binds complement
which complement protein does classic pathway activate
C1
what activates the alternative pathway
occurs spontaneously at a low rate, also microbial surface antigen (mannose especially)
what complement protein does the alternative system activate
C3
what activates the Lectin pathway
Mannose-binding lectin binds mannose on the surface of molecule (like microbes)
what two things are the most important opsonins
- C3b
2. IgG
Function of C3a
anaphylaxis–> stimulates mast cells and basophils to degranulate
Function of C5a
neutrophil chemotaxis (also involved with anaphylaxis)
What complement proteins involved in creation of the MAC
C5b, C5-C9
which complement protein helps clear immune complexes
C3b
What two proteins help prevent complement activation on self cells
- DAF
2. C1 esterase inhibitor
what CD is DAF
CD55
causes heriditary angioedema
C1 esterase inhibitor deficiency
recuurent pyogenic sinus and respiratory tract infections, increased susceptobility to type III HSN (glomerulonephritis)
C3 deficiency
recuurent Neisseria bacteremia, infections
C5-C9 deficiency (no MAC)
deficient in those with paroxsymal nocturnal hemoglobinuria
DAF (CD55) or GPI, which anchors DAF to the membrane
two CD not found on flow cytometry in paroxysmal nocturnal hemoglobinuria
- CD55
2. CD59
two clinical signs of PND
- hemosidinuria (due to chronic intravascular hemolysis)
2. thrombosis (platelets also damaged and release pro-thrombic substances)
hams test
for PND–> place RBS in acidic solution = lysis is + test
tx fr PND (3)
- transfusion
- warfarin
- Eculizumab (inhibits complement)
