Immunology Chapter 7

Front 1

the complement system is the major effector of the....

Back 1

humoral branch of the immune system

Front 2

RBC + serum>
RBC + Ab>
RBC + serum + Ab>

Back 2

ok
ok
lysed

Front 3

is complement a single protein?

Back 3

no it is 12 proteins

Front 4

does complement affect innate or adaptive?

Back 4

both

Front 5

4 functions of complement

p

Back 5

-lysis
-opsonization
-activatione of inflammatory response
-clearance of immune complexes

see page 169

Front 6

complement makes up what fraction of serum globulin?

Back 6

5%

Front 7

what is complement designated by?

Back 7

numerals (C1-C9)
letter symbols (factor D)
trivial names (homologous restriction factor)

Front 8

talk about the a and b fragment

Back 8

the b fragment is always larger....except in the case of C2

Front 9

ccomplexes with enzymatic activity are designated by what over the symbol?

Back 9

a bar will be over the symbol

Front 10

3 basic pathways complement can be activated in....don't describe

Back 10

-classical
-alternative
-lectin

Front 11

Descibe the classical pathway

p. 170 and 172

Back 11

170-172

Front 12

how are C1-4 found in the plasma normally?

Back 12

they are present in the plasma in functionally inactive forms

Front 13

C1 structure, and interaction, and random tidbits

p. 170-171

Back 13

C1qr2s2....it is a macromolecule with a molecule of q, 2 molecules of r and 2 molecules of s

-Structure is stabilized by calcium ion

-Each c1r and c1s monomer contains a catalytic domain with enzymatic activity and an interaction domain that facilitates binding with C1q or with each other

Front 14

IgM bound to membrane antigen vs serum antigen and binding to C1

Back 14

-membrane antigen will cause IgM to have stable conformation and will have 3 binding sites for C1

-circulating IgM, however, will be planar and there will be no C1q binding site

Front 15

IgG activating classical complement pathway

Back 15

It only has 1 binding site (remember IgM has 3)...and because of this, 2 molecules must be 30-40nm apart from each other on a target surface or in a complex

-a single molecule of igM bound to a rbc can activate complement system, but 1000 or more IgG molecules are needed to ensure that 2 molecules are close enough for to initiate c1q binding.

Front 16

how does C4b2a bind to bind?

Back 16

adjacent to antibody

Front 17

anaphylatoxins for chemotaxis
Inflammation!

Back 17

C3a- C5a

Front 18

opsonization for uptake by
phagocytic cells

Back 18

C3b, iC3b

Front 19

Membrane attack complex (M.A.C.)

Back 19

C5b-C9

Front 20

biological consequences of complement activation

Back 20

-opsonization for uptake by phagocytic cells

-anaphylatoxins for chemotaxis inflammation

-Membrane attack complex (MAC)

Front 21

whats type of complement to phagocytic cells have receptors for?

Back 21

C3

Front 22

alternative pathway involves what four serum proteins?

Back 22

c3, factor b, factor d and properdin

Front 23

in most cases how is the alternative pathway initiated?

Back 23

by cell surface constituents that are foreign to the host

Front 24

what are some initiaters of alternative pathway complement activation?

p. 173

Back 24

page 173

.....don't need to know all

Front 25

talk about c3 in alternative pathway

Back 25

c3 in serum has an unstable thioester bond: subject to slow spontaneous hydrolysis to yield C3a and C3b....c3b component can bind to foreign surface antigens....bacterial cells or viral particles

Front 26

diagram the alternative pathway

p. 174

Back 26

p. 174

Front 27

what do the membranes of most mammalian cells have?

Back 27

sialic acid: contributes to the rapid inactivation of bound C3b molecules on host cells: foreign cells do not have as much

Front 28

what does serum c3 contain?

Back 28

unstable thioester bonds....this leads it to spontaneous hydrolysis

Front 29

what does the MAC eventually do?

Back 29

forms a large channel through the membrane of the target cell, enabling ions and small molecules to diffuse freely across the membrane

Front 30

what is the end result of the classical, alternative or lectin pathway?

Back 30

production of an active C5 convertase

Front 31

when does the complement cascade go from being on the hydrophillic surface of membranes or immune complexes to creating exposure for hydrophobic regions that will bind to membrane phospholipids?

Back 31

as c5b6 binds to C7.....the hydrophobic binding sites allow it to anchor to the cell

Front 32

what is the amplification step in all pathways

Back 32

when c3 convertase converts c3 into c3a and c3b

Front 33

talk about the MAC

Back 33

-C5b6789

-initial C5b678 creates a 10A diameter pore....can lead to lysis of RBC's but not of nucleated cells

-final step is formation of the MAC is the binding and polymerization of C9, a perforin-like molecule, to the C5b678 complex...now has pore of 70-100A

p.178

Front 34

wht are regulatory mechanisms necessary for complement

Back 34

because elements of complement are capable of attacking host cells as well as foreign cells and microorganisms