Part 5: Overview of Adaptive Immunity

Question 1

Adaptive immune response

Answer 1

Acts against a specific intruder

Question 2

Adaptive immune response branches

Answer 2

Humoral (antibody mediated) immunity

Cellular (cell mediated) immunity

Question 3

Antibodies (Ab) are also called

Answer 3

Immunoglobulins (Ig)

Question 4

Glycoproteins are composed of

Answer 4

2 identical heavy chains

2 identical light chains

Question 5

Fab

Answer 5

2 identical antigen binding sites on the antibody

Question 6

Fc site

Answer 6

Interacts with other components of the immune system

Question 7

How many classes of antibodies are there?

Answer 7

5

Question 8

Immunoglobulin G (IgG)

Answer 8

Monomer
Most abundant antibody in blood and tissues
Most important for combating a pathogen

Question 9

Immunoglobulin M (IgM)

Answer 9

Pentamer
First antibody made when a new antigen is encountered
Excellent at agglutination
Does not leave blood and enter tissues

Question 10

Immunoglobulin A (IgA)

Answer 10

Dimer
Secreted into saliva, tears, mucous
Helps to protect mucosal surfaces

Question 11

Immunoglobulin D (IgD)

Answer 11

Monomer
Found on the surface of B cells
Plays a role in activating B cells to respond against an antigen

Question 12

Immunoglobulin E (IgE)

Answer 12

Monomer
Found on the surface of mast cells and basophils
Causes them to release granules of histamine
Triggers allergic response

Question 13

Antibodies have five major functions

Answer 13

Neutralization
Opsonization
Agglutination
Antibody mediated cytotoxicity
Complement activation

Question 14

Neutralization

Answer 14

Ab stick to antigens on a foreign particle and block attachment sites - stops bacteria, viruses, and toxins from entering host cells

Question 15

Opsonzation

Answer 15

Ab stick to a pathogen’s surface and flag down phagocytes
Phagocyte interacts with the Fc region and engulfs the pathogen
Greatly increases rate of phagocytosis

Question 16

Agglutination

Answer 16

Ab can stick to two identical antigens
Bridges particles together in clumps
Can be phagocytized more easily

Question 17

Antibody mediated cytotoxicity

Answer 17

Ab binds to antigen on the surface of a parasite
Fc can interact with eosinophils
Eosinophils release enzymes and reactive oxygen intermediates to attack the parasite

Question 18

Complement activation

Answer 18

Ab bound to a bacteria can activate complement
Results in the membrane attack complex (MAc)
Insert into bacterial membranes
Forms a pore
Cell leaks and dies

Question 19

Complement

Answer 19

A set of proteins in the blood that assist other components of the immune system
“Classical pathway” of complement activation

Question 20

Acquired

Answer 20

A pathogen must be encountered before the adaptive immune response is mounted

Question 21

Specific

Answer 21

Can mount a directed attack against a specific pathogen - immunity to one pathogen does not confer immunity to another

Question 22

Memory

Answer 22

Once a specific pathogen has been encountered immune system cells multiply and produce long living memory

Question 23

Tolerance

Answer 23

Inability to mount an adaptive immune response against self-antigens
Immune system cells that recognize self-antigens are destroyed during development

Question 24

Primary response

Answer 24

The first time a new pathogen is encountered, the adaptive immune response is weak

Question 25

What is the major result of primary response?

Answer 25

Immunologic memory

Question 26

Secondary response

Answer 26

The next time that pathogen is encountered memory cells are ready to response
Response can be so quick that the pathogen is unable to cause disease - immunity

Question 27

Immunogen

Answer 27

Any foreign particle that can induce an adaptive immune response
Normally large molecules - protein, polysaccharides, some lipids

Question 28

Antigen

Answer 28

Any substance that can react with antibodies or receptors on adaptive immune system cells

Question 29

Antibody

Answer 29

Proteins made by the immune system that can bind to, and inactive foreign antigens

Question 30

Epitope

Answer 30

The actual part of the antigen that can bind to antibody

Question 31

More epitopes on an antigen mean

Answer 31

The more immunogenic it will be and the more diverse population of antibodies can be generated against it

Question 32

Hapten

Answer 32

Low molecular weight compound too small to be immunogenic on its own, but can be highly antigenic

Question 33

Example of hapten

Answer 33

Penicillin

Question 34

Penicillin is small and non-immunogenic on its own

Answer 34

Can bind to proteins in the blood forming a strong immunogen

Antibodies are formed against it - leading to an allergic response