Complement Flashcards
Alteration of a complement (protein) in such a way that it can proceed to interact with the next component in the pathway (cascade)
Complement Activation
Utilization of complement components by the antigen-antibody complex.
Complement Fixation
Complements that have enzymatic activities
C1, C2, C3, C4
Complements that don’t have enzymatic activity
C5, C6, C7, C8, C9
Complement’s order of activation
C1, 4, 2, 3, 5, 6, 7, 8, 9
Complement’s order of discovery
C1, 2, 3, 4, 5, 6, 7, 8, 9
The dilution of a serum sample which can lyse a predetermined proportion of a sheep erythrocyte (srbc) suspension coated with anti-SRBC antibody.
Hemolytic Units
Denaturation (usually by heat) of one of the early components in -activation pathway resulting in the destruction of C-hemolytic activity.
Complement Inactivation
- Soluble and cell bounded protein
- Heat-labile proteins
- Predominantly inactive molecule
- All are produced on Liver
Characteristics of Complement
Small soluble proteins that regulate the immune system, orchestrating both innate immunity and the adaptive response to infection
Complement
Who coined the Complement System?
Paul Ehrlich
Who explain the nature of complement?
Jules Bordet
Where do Factor D come from?
Adipose Tissue
Where do C1 Components come from?
Intestinal Epithelial Cell
Other source come from?
Macrophage, Monocyte
Thermolabile in
56°C for 30 mins
It regains activity at what temperature?
7 - 37°C
It lost activity in ___ at ___?
3 - 4 days at Refrigerator temperature
It deteriorates within ___ at ___?
1 - 2 days at room temperature
It reacts best at ___ in ___?
pH 7.2 - 7.4 in 30 - 37°C
(True or False)
It has Calcium and Magnesium
True
(True or False)
It is bound to all antigen-antibody complexes
True
(True or False)
It CANNOT be activated by non-serologic reactions
False
Complement is preserved BEST by ____?
Lyophilization
What are the 3 phase for each of the main pathway?
- Initiation
- Amplification
- Membrane Attack Complex (MAC)
Its activation proteins are C1qrs, C2, C3, and C4. What pathway is this?
Classical pathway
Its activation proteins are MBP, MASP, MASP2. What pathway is this?
Lectin pathway
Its activation proteins are C3, Factor B, and D Properdin. What pathway is this?
Alternative pathway
It has C5, C6, C7, C8, and C9. What pathway is this?
Lytic pathway
Its Stimulus has Antigen-Antibody complexes, CRP, E.coli, Mycoplasma, Protozoa
Classical
Its stimulus is Lipopolysaccharide, Fungal Cell [zymosan], Yeast, Parasites [trypanosmoes, tumor cell lines, Cobra venom factor
Alternative
Its stimulus is mannose and several other sugars found primarily on bacteria, some yeasts, viruses, and several parasites
Lectin
A pathway that is not calcium-dependent cause it has magnesium
Alternative
These pathways are calcium dependent
Classical and Lectin
What are the common Activation unit of the 3 pathways?
C3 convertase and C5 convertase
Membrane Attack Complex (MAC)
C5, C6, C7, C8, C9
What are the 3 pathways of complement activation?
- Classical pathway
- Alternative pathway
- Lectin pathway
It bind to fc portion of IgG (CH2) & IgM (CH3) ; B binds to C3b to form C3 convertase
C1q
Cleaves to C4 & C2 ; D - Cleaves to factor B into Bb in the presence of C3 and Mg ions
C1s
This is the key component of each pathway ; Properdin - stabilize C3 convertase
C3