MIIM - The Immune System and the Response to Infection - Week 4

Question 1

What are the four principles of immune responses?

Answer 1

Immunological recognition
Immune effector functions
Immune regulation
Immunological memory

Question 2

What are pathogen associated molecular patterns?

Answer 2

Microbial molecules that are unique to microbes but are shared within discrete taxonomic groups like LPS and flagella

Question 3

Which evolved second, the innate or adaptive immune system? what was this evolution in response to?

Answer 3

Innate evoled first - adaptive evolved in response to microbes that were able to evade the innate immune system.

Question 4

Do both the innate and adaptive immune system aid in anti-tumour activity?

Answer 4

Yes

Question 5

Define specific and non-specific immune system.

Answer 5

Specific is the adaptive immune system
Non-specific is the innate immune system

Question 6

Which immune system is the first line of defence?

Answer 6

Innate

Question 7

Name 8 organs and tissues associated with the immune system.

Answer 7

Adenoids
Tonsils
Thymus
Lymph nodes
Lymph vessels
Spleen
Peyer’s patches
Bone marrow
Skin

Question 8

Name 8 examples of the 1st line of defence.

Answer 8

Lysozyme in tears
Skin surface including fatty acids and normal flora
Rapid pH change in the GIT
Removal of particles by cilia in the nasopharynx
Mucus lining the tracea
Stomach pH of 2
Normal GIT flora
Flushingof the urinary tract

Question 9

Which is more rapid, innate or adaptive?

Answer 9

Innate

Question 10

What are the most common WBCs in our bodies?

Answer 10

Neutrophils

Question 11

What cell is the origin for all blood cells?

Answer 11

Pluripotent haemopoietic stem cells

Question 12

Name 3 kinds of specialised plasma factors that mediate innate immunity.

Answer 12

C-reactive proteins
Mannose binding lectin
Complement proteins

Question 13

Where are complement proteins, and can they be upregulated?

Answer 13

Made in the liver, upregulated in response to an infection

Question 14

Define acute phase proteins.

Answer 14

Proteins that are rapidly produced in response to an infection

Question 15

What process does mannose binding lectin trigger?

Answer 15

Complement cascade

Question 16

What process does c-reactive proteins trigger?

Answer 16

Complement cascade

Question 17

What is the critical step of complement cascade?

Answer 17

Breakdown of C3

Question 18

Define complement terms -a and -b.

Answer 18

-a is used for a smaller cleaved protein fragment
-b is the larger fragment

Question 19

Describe three pathways to activate the complement cascade.

Answer 19

Classical - antibody binding
Lectin - mannose binding
Alternate - pathogen surfaces

Question 20

What is C3b responsible for?

Answer 20

Coats microbes inducing phagocytosis

Question 21

Define opsonisation.

Answer 21

Coating with a phagocytosis-inducing molecule

Question 22

What complement proteins are responsible for pore formation and lysis?

Answer 22

C5-C9

Question 23

What three complement proteins are responsible for recruitment of inflammatory cells, and what is this process called?

Answer 23

C4a, C4a, and C5a.
This is chemotaxis (they also induce inflammation)

Question 24

Name 7 leucocytes of the innate immune systen.

Answer 24

Neutrophils
Monocytes
Macrophages
Dendritic cells
Eosinophils
NK cells
Basophils

Question 25

What 4 innate immune leucocytes engulf extracellular material?

Answer 25

Neutrophils Monocytes Macrophages Dentritic cells

Question 26

What two innate immune leucocytes kill eukaryotic parasites or altered cells?

Answer 26

Eosinophils NK cells

Question 27

Which innate immune leucocyte releases immunomodulatory compounds?

Answer 27

Basophils

Question 28

How do macrophages activate T cells?

Answer 28

After phagocytosis, they present foreign antigens to the T cells, which activates them.

Question 29

What are cytokines?

Answer 29

Proteins secreted by cells that interacts with and affects the behaviour of nearby cells with the appropriate receptors.

Question 30

What are chemokines?

Answer 30

A secreted protein that attracts cells with the appropriate receptors.

Question 31

Describe the five stages of phagocytosis.

Answer 31

Pseudopod engulfs the bacteria Phagosome formation and acidification Phagolysosome formation Lysosomal protein degradation of the bacteria Release of bacterial fragments

Question 32

Name 6 ways phagocytes can kill bacteria.

Answer 32

Acidification Antimicrobial peptides Enzymes Competitors Toxic nitrogen intermediates Toxic oxygen intermediates

Question 33

Where do B- and T-cells mature?

Answer 33

B-cells mature in the bone marrow T-cells mature in the thymus

Question 34

Where do mature B- and T-cells end up after maturation?

Answer 34

B-cells go to the blood T-cells go to the blood and lymph

Question 35

What three actions does a B lymphocyte have?

Answer 35

Neutralisation of a microbe via antibodies (agglutination) Phagocytosis Complement activation

Question 36

What three actions does a helpter T-cell have?

Answer 36

Activation of macrophages Inflammation Activation of T- and B-lymphocytes

Question 37

What action do cytotoxic T-cells have?

Answer 37

It kills cells that express microbial antigens

Question 38

What action do natural killer cells have?

Answer 38

It kills cells expressing abnormal glycoproteins

Question 39

What are humoral and cellular immunity, and under what kind of immune system (innate or adaptive) do they fall under?

Answer 39

Humoral - B-cell response Cellular - T-cell response They both fall under the adaptive immune system

Question 40

What are the 2 main functions of humoral immunity?

Answer 40

Blocks infections and eliminates extracellular microbes

Question 41

What are the 3 main functions of cellular immunity?

Answer 41

Activates macrophages to kill phagocytosed microbes Kills infected cells Eliminates reservoirs of infection

Question 42

Name 4 immune recognition features of adaptive immunity.

Answer 42

Each lymphocyte recognises a single antigen The lymphocyte population is highly diverse in antigen receptors It responds to a large variety of antigens It can discriminate self from non-self

Question 43

What is the main response of adaptive immune response.

Answer 43

Clonal expansion

Question 44

Which immune system prevents injury to the host during the response to foreign entigens.

Answer 44

Adaptive immune response