The Immune system III (Lecture 7)

Question 1

What are the 4 steps to phagocytosis?

Answer 1

Attachment
Specific: damaged cells or protein- targeted cells
Proteins = opsonins

Internalization
Takes approximately 0.01 sec
Phagosome + lysosome → secondary lysosome

Degradation
Lysosome enzymes degrade phagocytosed product

Exocytosis
Elimination of some degradation products

Question 2

______ communicate between leukocytes. Examples of these are IL-1, IL-6, TNF-α.

Answer 2

Interleukins

Question 3

What are the actions of interleukins and TNF-α. in bone marrow?

Answer 3

Helps produce and secrete more leukocytes by:

• Act as endogenous pyrogens
• Stimulate fever via hypothalamus
• Hypothalamus increases body temperature via prostaglandins

Question 4

______ is the proinflammatory cytokine

Answer 4

IL-6

Question 5

______ stimulates proliferation and differentiation of B and T lymphocytes

Answer 5

IL-1

Question 6

Natural killer cells recognize abnormal or infected cells that cause lysis of pathogen by secreting ______.

Answer 6

Perforins

Question 7

True or False: Natural killer cells can attack virus-infected cells without identifying virus

Answer 7

True

Question 8

True or False: Natural killer cells can attack and destroy tumour cells.

Answer 8

True

Question 9

______ are proteins secreted by leukocytes and virus-infected cells induce virus resistance in neighboring cells.

Answer 9

Interferons

Question 10

______ is secreted from active T cells and NK cells and inhibits viral replication.

Answer 10

Interferon-γ

Question 11

What are the 3 pathways involved in the activation of the compliment system?

Answer 11

Classical, lectin and alternative

Question 12

The ______ pathway binds to antibodies attached to bacteria, the ______ pathway binds to mannose-containing carbohydrates on bacteria or viruses, and the ______ pathway binds to carbohydrates on bacterial cell walls.

Answer 12

Classical, lectin and alternative

Question 13

What are the 4 complement protein functions?

Answer 13

• Form (membrane attack complex) MAC to lyse cell
• Chemotaxis
• Trigger histamine release from mast cells
• Act as opsonins (phagocytes)

Question 14

______ recognize these structures and target them for clearance by allowing ______ to bind to the specific patter recognition receptor

Answer 14

PRR
PAMP
Pathogen Associated Molecular Pattern

Question 15

What type of PRR recognizes cell wall components?

Answer 15

C-type lectin receptors (CLR)

Question 16

What type of PRR recognizes viral double-stranded RNAs

Answer 16

RIG-I

Question 17

What type of PRR recognizes both intracellular and extracellular pathogens

Answer 17

Toll like receptors (TLR)

Question 18

______ immunity is B-cell mediated and involves secretion of antibodies by plasma cells,

Answer 18

Humoral

Question 19

______ immunity is T cell mediated and involves lysis of cells by cytotoxic T cells

Answer 19

Cell-mediated

Question 20

What are the 4 features of specific immune response?

Answer 20

Specificity
Diversity
Memory
Self-tolerance

Question 21

What is associated with specificity in specific defense immune response.

Answer 21

Antigens

Question 22

______ are recognition sites for B or T cells.

Answer 22

Epitopes

Question 23

In the antibody structure how are the heavy chains and light chains interconnected?

Answer 23

Disulfide bridges

Question 24

What isdiversity in specific defense immune response.

Answer 24

Diversity in B- and T-cell antigen receptor types allows the immune system to recognize millions of antigens

Question 25

What are the types of B lymphocytes?

Answer 25

``` Effector cells (plasma cells) Memory B cells ```

Question 26

The ______ response takes 10-17 days after exposure and antigen-selected B and T cells proliferate and differentiate into effector cells

Answer 26

Primary immune

Question 27

The ______ response takes 2-7 days to occur and the response has greater magnitude and is more prolonged.

Answer 27

Secondary immune

Question 28

______ evoke production of plasma cells and memory B cells and ______ activate B cells without T cell help (Proliferate without IL-2 and cannot develop memory cells)

Answer 28

T-dependent antigens T-independent antigens

Question 29

What is the most common class of antibody produced in the primary response to antigen?

Answer 29

IgM

Question 30

What is antibody is involved in allergies such as hay fever?

Answer 30

IgE

Question 31

What antibody crosses epithelial cells, so is present on mucosal surfaces and in breast milk; is important in immunity in newborns?

Answer 31

IgA

Question 32

What is the most common class of antibody in the blood, and the major class of antibody produced in secondary responses.

Answer 32

IgG

Question 33

* ______ and ______: activate complement * ______: opsonization * ______: histamine release from mast cells and basophils * ______: NK cells

Answer 33

IgM and IgG IgG IgE IgG

Question 34

What are the 5 types if antibody functions?

Answer 34

``` Neutralization Agglutination Opsonization Complement activation Enhanced NK cell activity ```