Chapter 18.3 Adaptive Immune Response

Question 1

Any molecule that can trigger an adaptive immune response against itself or the cell bearing it is called an ______

Answer 1

antigen

Question 2

What are the three stages of a typical adaptive immune response?

Include: how lymphocytes are activated; clonal expansion

Answer 2

1. the encounter and recognition of an antigen by lymphocytes.
   
   • each lymphocyte is specific for just one type of antigen
2. Lymphocyte activation
   
   • binding of antigen to receptor activates lymphocyte
   • activated lymphocyte undergoes many rounds of cell division = clonal expansion
3. The attack launched by the activated lymphocytes and their secretions

Question 3

What are the two possible functions of the many lymphocytes produced from clonal expansion?

Answer 3

Clonal expansion: rapid cell division by lymphocytes resulting in many daughter lymphocytes that recognize the same antigen as the parent

• some of these lymphocytes will function as effector lymphocytes to carry out the attack response
• others will be set aside as memory cells poised to recognize the antigen if it returns

Question 4

Fill in the blanks detailing the attack launched by the activated lymphocytes and their secretions (phase 3 of adaptive immune response). Ideally, you want to recall the events during this phase without the hints of a fill in the blank question.

Activated _______ which comprise one group of lymphocytes, differentiate into ______ that secrete _____ into the blood which _____ pathogens or foreign substances and target them for attack by _____ _____ _____.

Activated ______ another type of lymphocyte, directly attack and kill the cells bearing the antigens.

Answer 4

Activated B-cells which comprise one group of lymphocytes, differentiate into plasma cells that secrete antibodies into the blood which opsonize pathogens or foreign substances and target them for attack by innate immune cells.

Activated cytotoxic T-Cells another type of lymphocyte, directly attack and kill the cells bearing the antigens.

Question 5

What happens to the cells that participated in Adaptive immune response after the attack is successfully completed.

(name those cells and the homeostatic purpose)

Answer 5

• B-cells, plasma cells, and T-cells that participated in the attack die by apoptosis
• Memory cells persist even after immune response is completed

-homeostatic response that prevents the immune response from becoming excessive and potentially destroying its own tissue

Question 6

Where is the majority of lymphocytes?

Answer 6

in the lymphoid organs

Question 7

What are the primary lymphoid organs?

Answer 7

Thymus and bone marrow

Question 8

The primary lymphoid organs are the initial sites of ______ ______

Answer 8

The primary lymphoid organs are the initial sites of lymphocyte development

Question 9

Primary lymphoid organs (bone marrow and thymus) supply the body with mature but ______ lymphocytes

Answer 9

Primary lymphoid organs (bone marrow and thymus) supply the body with mature but naive lymphocytes

Question 10

What is a naive lymphocyte?

Answer 10

Lymphocytes that have not yet been activated by specific antigen

Question 11

What are the Secondary Lymphoid organs?

Answer 11

Lymph nodes, spleen, tonsils, and lymphocyte accumulations in the linings of the intestinal, respiratory, genital, and urinary tracts

Question 12

Where are naive lymphocytes activated to participate in adaptive immune response?

Answer 12

The secondary lymphoid organs

Question 13

All lymphocytes are descended from ancestors that matured in the _____ or ____ but may not themselves have ______ in those organs

Answer 13

All lymphocytes are descended ​from ancestors that matured in the bone marrow or thymus but may not themselves have arisen in those organs

Question 14

fluid flowing through the lymphatic vessels is called ______, which is ______ that has entered the lymphatic capillaries and is routed to the ________ that drain into systemic veins

Answer 14

fluid flowing through the lymphatic vessels is called lymph, which is interstitial fluid that has entered the lymphatic capillaries and is routed to the large lymphatic vessels that drain into systemic veins

Question 15

On it’s way from lymphatic capillaries to large lymphatic vessels and into systemic veins, lymph flows through ______

Answer 15

lymph nodes

Question 16

The ______ is the largest of the secondary lymphoid organs and lies in the left part of the abdominal cavity between the stomach and the diaphragm

Answer 16

The spleen is the largest of the secondary lymphoid organs and lies in the left part of the abdominal cavity between the stomach and the diaphragm

Question 17

The ____ and _____ are a group of small, rounded lymphoid organs in the pharynx. They are filled with _____, _____ and _____ and have openings called ____ to the surface of the pharynx

Answer 17

The tonsils and adenoids are a group of small, rounded lymphoid organs in the pharynx. They are filled with lymphocytes, macrophages and dendritic cells and have openings called crypts to the surface of the pharynx

Question 18

Upon activation, B cells differentiate into _______, which secrete ______

Answer 18

Upon activation, B cells differentiate into plasma cells, which secrete antibodies

Question 19

What are antibodies?

Answer 19

proteins that travel all over the body to reach antigens identical to those that stimulated their production

Question 20

____________ responses have an extremely wide diversity of targets and are the major defence against bacteria, viruses, and other pathogens in the extracellular fluid and against toxic molecules (toxins)

Answer 20

Antibody-mediated responses have an extremely wide diversity of targets and are the major defence against bacteria, viruses, and other pathogens in the extracellular fluid and against toxic molecules (toxins)

Question 21

What is another name for antibody-mediated response?

Answer 21

Humoral responses

Humoral = communication by way of soluble chemical messengers

Question 22

T-Cell responses are called _______ responses

Answer 22

T-Cell responses are called cell-mediated responses

Question 23

What are the two major functional subsets of T-cells?

Answer 23

1. Cytotoxic T-cells
2. Helper T-cells

Question 24

A third subset of T-cells has recently been recognized and is called ______, which _____

Answer 24

A third subset of T-cells has recently been recognized and is called regulatory T-cells, which inhibit the function of both B cells and cytotoxic T-cells

Question 25

Cytotoxic T-cells have ______ proteins in their plasma membrane and so are also called ______

Answer 25

Cytotoxic T-cells have CD8 proteins in their plasma membrane and so are also called CD8+ (CD8 positive) cells

Question 26

Helper T-cells and Regulatory T-cells express the ______ protein in their plasma membranes and so are called ______

Answer 26

Helper T-cells and Regulatory T-cells express the CD4 protein in their plasma membranes and so are called CD4+ (CD4 positive) cells

Question 27

What is an important geographic difference in antibody-mediated responses and responses activated by cytotoxic T Cells

Answer 27

• B cells (and plasma cells derived from them) remain in whatever location the recognition and activation steps occurred. They send their antibodies through the blood to seek out antigens identical to those that triggered the response
• Cytotoxic T cells must enter the blood and seek out the targets

Question 28

Helper T-Cells go through the usual first two stages of the immune response - name them

Answer 28

1. they combine with antigen
2. They undergo activation

Question 29

Once activated, Helper T-cells migrate to ______. B cells that have a bound antigen present it to the __________

Answer 29

Once activated, Helper T-cells migrate to the site of B-cell activation. B cells that have a bound antigen present it to the activated helper cells

Question 30

What induces B-cell activation

Answer 30

Antigen-specific helper T cells make direct contact with the B-cell and communicate with surface receptors (and the secretion of cytokines) thus inducing the B cell activation

Question 31

What do B-cells and cytotoxic T cells require in order to function adequately?

Answer 31

They must be stimulated by cytokines from helpter T cells

Question 32

Regulatory T cells are believed to suppress the ability of certain ____ and ______ to attack a person’s own _____ (which can occur in diseases known as ______ diseases)

Answer 32

Regulatory T cells are believed to suppress the ability of certain B and cytotoxic T cells to attack a person’s own proteins (which can occur in diseases known as autoimmune diseases)