Ch17 Basic Principles of Adaptive Immunity and Immunization

Question 1

Adaptive Immunity (aquired)

Answer 1

immunity obtained in some matter other than heredity Can be naturally acquired or artificially acquired. Can also be active or passive

Question 2

Naturally acquired adaptive immunity

Answer 2

immunity that is acquired after having a specific disease. Can also be acquired from antibodies transferred to fetus across the placenta or to an infant in colostrum and breast milk.

Question 3

Artificially acquired adaptive immunity

Answer 3

immunity that is obtained by receiving an antigen by the injection of vaccine or immune serum that produces immunity

Question 4

Active Immunity

Answer 4

created when the person’s own immune system activates t cells, or produces antibodies or other defenses against an infectious agent. Can be either naturally or artificially acquired

Question 5

Naturally acquired active immunity

Answer 5

produced when a person is exposed to an infectious agent

Question 6

Artificially acquired active immunity

Answer 6

produced when a person is exposed to a vaccine containing live, weakened, or dead organisms or their toxins.

Question 7

Passive Immunity

Answer 7

created when ready made antibodies are introduced into the body. Passive because the hosts immune system does not make antibodies. Can be either naturally or artificially acquired

Question 8

Naturally acquired passive immunity

Answer 8

produced when antibodies made by a mother’s immune system are transferred to her offspring

Question 9

Artificially acquired passive immunity

Answer 9

produced when antibodies made by other hosts are introduced into a new host.

Question 10

Antigen

Answer 10

a substance the body identifies as foreign and toward which it mounts an immune response

Question 11

Epitope

Answer 11

also called antigenic determinants; areas on the molecule to which antibodies can bind

Question 12

Hapten

Answer 12

a small molecule that can act as an antigen if it binds to a larger protein molecule. Also can act as eptiopes on the surfaces of proteins,

Question 13

Humoral Immunity

Answer 13

carried out by antibodies circulating in the blood. When stimulated by an antigen, B lymphocytes initiate a process that leads to the release of antibodies.

Question 14

Cell-mediated immunity

Answer 14

carried out by T cells. It occurs at the cellular level, especially in situations where antigens are embedded in cell membranes or are inside host cells and are thus inaccessible to antibodies.

Question 15

Adaptive Immunity must be able to do the following

Answer 15

(1) recognize self vs non self
(2) specifically react to each antigen that it encounters
(3) have heterogeneity so that every antigen will cause a specific immune response to it
(4) Be able to remember that it has seen the antigen, so if one is exposed to the antigen a second time, the immune response will be faster than the first encounter with the antigen. The quantity of antibody produced during the secondary response will also be greater than during the primary response

Question 16

Plasma Cells

Answer 16

possesses the specific monomer IgM antibody on its surface that can recognize and bind to antigens. This stimulates the B cell to produce antibodies. The type of b cell that secretes antibodies is known as a plasma cell

Question 17

Immunoglobulins (Ig)

Answer 17

the basic units of antibodies. Y shaped protein molecules that are composed of four polypeptide chains, two identical light chains and two identical heavy chains. The chains possess constant regions and variable regions

Question 18

Constant Region

Answer 18

determines the particular class that an immunoglobulin belongs to

Question 19

Variable region

Answer 19

has a particular shape and charge that enables the molecule to bind a particular antigen

Question 20

5 classes of antibodies

Answer 20

IgG, IgM, IgA, IgE, IgD

Question 21

IgG

Answer 21

the antigen binding sights of IgG attach to antigens on microorganisms, and their tissue binding sights attach to receptors on phagocytic cells. Also activates the complement system. The only immunoglobulin that can cross the placenta from mother to fetus

Question 22

IgA

Answer 22

Guards entrances to the body by binding antigens on microorganisms before they invade tissues. Also activates the complement system

Question 23

IgM

Answer 23

the first antibody secreted into the blood during the early stages of a primary response. Also activates the complement system and is the first antibody formed in life.

Question 24

IgE

Answer 24

Has a special affinity for receptors on the plasma membranes of basophils in the blood or mast cells in the tissue. Plays a damaging role in the development of allergies to such agents as drugs, pollens, and certain foods.

Question 25

IgD

Answer 25

found mainly on B cell membranes and rarely secreted, function is unknown

Question 26

Primary Humoral Response

Answer 26

Occurs when the antigen is first recognized by host B cells. After recognition, B cells divide to form plasma cells, which begin to synthesize antibodies. The first antibodies are IgM. Next, cytokines cause a switch in class and IgG is produced. Eventually production of the two antibodies wanes, and they become virtually undetectable. However, B cells that have proliferated and formed memory cells persist within the lymphoid tissue.

Question 27

Secondary Humoral Response

Answer 27

Occurs when an antigen recognized by memory cells enters the blood. The presence of memory cells makes this response much faster than the first. IgM and IgG are produced in the same order. However, IgM is produced in smaller quantities over a shorter period and IgG is produced sooner and in much larger quantities.

Question 28

T cell independent antigens.

Answer 28

antigens that bind to and activate B cells without the help of Helper T cells.

Question 29

T cell dependent antigens

Answer 29

Antigens that must activate both a B cell and a Helper T so that they can make contact with eachother. Once the two make contact, the B cell activates the Helper T cell causing it to secrete lymphokines that further activate the B cell causing it to differentiate and proliferate.

Question 30

Antibody Mechanisms to Destroy foreign agents

Answer 30

neutralization, opsonization, and cell lysis

Question 31

Neutralization

Answer 31

inactivation of bacterial toxins through the formation of antigen-antibody complexes

Question 32

Opsonization

Answer 32

found in last set of flash cards

Question 33

Cell lysis

Answer 33

Antibodies bind to the microbe and break down its plasma membrane, causing it to lyse

Question 34

Monoclonal antibodies

Answer 34

antibodies produced in the laboratory by a clone of cultured cells that make one specific antibody. One method involves myeloma cells (malignant immune system cells) that are mixed with sensitized lymphocytes. They then fuse together to make a hybridoma, which contains genetic info from both and produces large quantities of antibody.

Question 35

Helper T Cells

Answer 35

stimulated when they are presented with an antigen (attatched to the MHC II protein) from a macrophage or B cell. Once stimulated, the helper T cells release chemical mediators, like interlukins and lymphokines, which can either help B cells or stimulate macrophages.

Question 36

Cytotoxic T Cells

Answer 36

stimulated when the antigen is presented (attatched to MHC I protein) from a macrophage. This T cell can now kill infected cells directly by releasing perforins directly into the infected cells.

Question 37

Natural Killer cells

Answer 37

NK cells do not need to be presented with the antigen from the macrophage to become activated but they also destroy cells by releasing perforins into them

Question 38

Delayed Hypersensitivity T Cells

Answer 38

once sitmulated by antigen, release a number of lymphokines, which attract macrophages to get to the site of the infection as well as cause an increase in macrophage activity

Question 39

Immune response to bacterial infection

Answer 39

(Bacterial): certain immune responses alter the invading organisms so that they can be phagocytized. Plasma cells also make specific antibodies that can interfere with a any of several steps in bacterial invasion. They can prevent bacterial attachment to cell surfaces, opsonize bacteria, and neutralize bacterial toxins or inactivate bacterial enzymes.

Question 40

Immune response to viral infection

Answer 40

Interferons, secretory IgA, and some IgG anitbodies prevent or minimize entry of viruses. IgG and IgM act in the blood to neutralize viruses directly or to promote their destruction through complement. Cytotoxins and cellular immunity via TC cells and NK cells are especially important. Fever also plays a role.