Introduction to the immune system

Question 1

What are the four kinds of pathogens?

Answer 1

• bacteria (Extracellular and intracellular)
• Viruses (Intracellular)
• Fungi (Extracellular)
• parasites
    -Protozoans and helminths 
    -Extracellular

Question 2

Host response that prevents or combat infection and cancer

Answer 2

Immunity

Question 3

Foreign substance, including part of infectious agent, that induces a specific immune response

Answer 3

Antigens (immunogens) 

Question 4

• ability to induce an immune response

- All around us in nature

Answer 4

Immunogenicity (Antigenicity) 

Question 5

• A molecule too small to inflict an immune response unless attached to a larger molecule like a protein
• however it can be recognized by an existing immune response

Answer 5

Hapten

Question 6

• The part of antigen that anybody or T cell receptor recognizes
• A single antigen can have several of the same or different __________.

Answer 6

Epitope (antigenic determinant) 

Question 7

• protein that binds to a specific antigen which help eliminate the antigen
• produced by B cells

Answer 7

Antibody

Question 8

• peptides produced by cells, often cells of immune system, that help activate, suppress, or regulate other cells
• Think of them as hormones of the immune system

Answer 8

Cytokines

Question 9

What are examples of physical barriers?

Answer 9

Skin, tears, mucus, etc.

Question 10

Innate immunity is also known as…

Answer 10

Non-specific “natural immunity”

Question 11

What are the two subtypes of innate immunity?

Answer 11

• resident

- Induced (Inflammation, activated macrophages, etc.

Question 12

What are the two subtypes of adaptive immunity?

Answer 12

• Humoral (Antibody-mediated)

- cell-mediated (effector T cells) 

Question 13

True or false, there is a lot of interactions and overlap between innate and adaptive immunity?

Answer 13

True

Question 14

What are three major components of innate immunity? 

Answer 14

• phagocytes (Neutrophils, Monocytes/macrophages)
• NK cells (Kill virally infected and tumor cells, produce cytokines)
• complement (Enhances phagocytosis, recruit cells, kills cells/bacteria)
• Inflammation

Question 15

What are two major characteristics of adaptive immunity?

Answer 15

Specificity and memory

Question 16

What is the major cell type In adaptive immunity?

Answer 16

Lymphocytes
• B lymphocytes that produce antibodies
• T lymphocytes that regulate immunity, kill infected cells, activates macrophages, etc.

Question 17

Do B lymphocytes or a T Lymphocytesrecognize naïve (whole) antigens?

Answer 17

B lymphocytes

-They also are one of the antigen presenting cells to T cells

Question 18

Recognizes antigenic peptides presented by antigen presenting cells (Dendritic cells, macrophages, and B cells) 

Answer 18

T lymphocytes

Question 19

Regulates immunity, kills infected cells, activates macrophages, etc.

Answer 19

T lymphocytes

Question 20

_______________ T cells (CD__+ T cells) kills virally infected and cancer cells, as well as cells with intracellular bacteria

Answer 20

Cytotoxic, 8

Question 21

T helper cells (CD___+ T cells)

Answer 21

4

Question 22

What cells play a major role in cell mediated immunity?

Answer 22

Antigen-specific T cells
• cytotoxic T cells
• activation of macrophages by Th1 cells

Question 23

T cells recognize peptide bound to…..

Answer 23

Histocompatibility complex (MHC) Molecules on antigen presenting cells (APC) 

Question 24

Interactions between other cells surface molecules on APC and T cells

Answer 24

Second co-Stimulatory signal

Question 25

CD8+ T cells: MHC ___

Answer 25

1. endogenous antigen

Question 26

CD4+ T cells: MHC___

Answer 26

II exogenous antigen

Question 27

What two things happen during clonal selection?

Answer 27

- Eliminate self reactive cells | - expand cells specific for antigen

Question 28

For clonal selection, What else is required besides Antigen recognitionan for activation of lymphocytes?

Answer 28

- T cell recognize peptide bound to major MHC molecules on APC - need second co-stimulators signal e.g. interactions between other cell surface molecules on APC and T cells (without secondary signal —-> anergy)

Question 29

Co-stimulatory signal plus specific signal —-> activates T cell while…. Specific signal alone ———-> T cells becomes _______.

Answer 29

anergic

Question 30

Type of immunity that is generated by the individual. | Long-term but takes time to generate

Answer 30

Active immunity Ex: vaccination

Question 31

Type of immunity that is transferred. | Rapid but transient

Answer 31

Passive immunity Ex: anti-venom, maternal antibody (IgG)

Question 32

Generation of immune response against another individual

Answer 32

Isoimmunization