Complement System

Front 1

Interaction of antibodies with antigens can result in?

Back 1

-removal of toxins
-coating a pathogen to inhibit invasion of host
-initiation of an effector mechanism

Front 2

Basic features of the complement system are?

Back 2

-about 30 proteins circulating in the blood
-precursors are cleaved by enzyme and then become enzyme (serine proteases)
-ever expanding cascade of actions

Front 3

The complement system consists of three major pathways?

Back 3

Classic
Alternate
Membrane Attack

Front 4

The Classic Complement pathway is stimulated by what and where?

Back 4

-C1q binding to one IgM or many IgG
-on a cell surface *or* in the plasma

Front 5

C1 exists where and consists of what?

Back 5

in plasma as free floating
2C1r, 2C1s, 6C1q

Front 6

C1r does what?

Back 6

Cleaves C4 into C4a and C4b,
Cleaves C2 into C2a and C2b

Front 7

C3 convertase complex can be formed by?

Back 7

C3b*Factor B (C3b*Bb), or
C4b*2b

Front 8

C4b binds where and what and how to each?

Back 8

-covalently to sugar residues on cell-surface glycoproteins
-non-convalently to C2b

Front 9

C4b2b is known as

Back 9

-C3 convertase, and
-C3/C5 convertase

Front 10

C3 is cleaved by whom into what?

Back 10

-C3 convertase (C4b2b or C3b*Bb) into C3a and C3b
-can also spontaneously cleave

Front 11

C3a, C4a, and C5a are what?

Back 11

anapholotoxins

Front 12

C3b binds where to attract what and therefore can be known as?

Back 12

Binds covalently to *glycoproteins* scattered across a cell or other surface.

Attracts Macrophages and Neutrophils to the C3b-coated cell or particle preparatory to phagocytosis.

This effect qualifies C3b as an opsonin.

Also binds to C5 to become a C5 convertase.
Also binds to Bb to become a C3 convertase
or to C3bBb to become a C5 convertase

Front 13

C5b binds what to form what to allow?

Back 13

1 C6, 1 C7, 1 C8 and up to 19 C9 to form the membrane attack complex allowing enterance of ions into cell.

Front 14

Factor B can bind to what forming what?

Back 14

C3b*Bb - Factor C3 convertase
C3b*Bb*C3b - Factor 5 convertase and thus membrane attack complex

Front 15

Self is protected by C3b by

Back 15

sialic acid on outside of cells
downregulation of complement activity

Front 16

Complement activity is downregulated by?

Back 16

Factor H binding to Factor B, Breaking feedback loop
Factor I, Inactivating C3b
C1INH, inhibiting cleavage of C2 and C4 by C1

Front 17

Genetic disorders of complement products include?

Back 17

C3 or C9 deficiency - prone to bacterial infections
C1,C2,C4 (early products) - autoimmune such as Lupus
C1INH - some sort of crazy edema

Front 18

Breakdown of C3b results in production of what that is taken in by?

Back 18

C3d is taken in by dendritic cells and B cells.

Front 19

C3d antigen complex enters B cells with the same receptor as this pathogen?

Back 19

Epstein-Barr Virus

Front 20

The EBV can cause what?

Back 20

mononucleosis
Burkitt's lymphoma

Front 21

complement-mediated lysis can cause such serious disorders as

Back 21

Rh disease
immune hemolytic anemia (SLE)
immune thrombocytopenic purpura

Front 22

Complement effector functions include

Back 22

solubilizing antibodies - early products
vascular permeability -C3a, C5a
attracting phagocytic cells -C5a
cell lysis
opsonization aiding in phagocytosis -C3b