COMPLEMENT Meaning -
to Help or to make Complete
COMPLEMENT year
1890s
Coined the term:
Paul Ehrlich
Elucidate the control of the complement; Novel price
Jules Bordet
A primary part of the
Innate immune response
Substance under the
humoral-mediated immunity
Group of
30 different proteins
Designation
• Numerals (C1-C9)
• Letter symbols (factor D)
Cleavage Products – enzyme activation
a and b
named with a capital C followed by a
number
small letter
Ex. C3a/ C3b
• Larger fragment- designated as
• Smaller fragment- designated as
b
a
Exception:
C2 fragments
Larger-
smaller fragment-
C2a
C2b
Functions of Complement
Proteins and glycoproteins synthesized mainly by
liver hepatocytes
Most circulate in the serum functionally inactive forms as
proenzymes or zymogens
PRODUCES A
CASCADE PHENOMENON
WHERE THE PRODUCT OF ONE REACTION IS THE (?) OF THE NEXT
ENZYMATIC CATALYST
Heat Labile: destroyed when heated at
56°C for 30 mins
Anaphylatoxin
C3a, C4a, C5a
Increase Capillary Permeability
Role of C2b fragment
Chemotaxis
C5a
Virus neutralization
C4