Lecture 1: Introduction

Question 1

What is the most significant disease to be eradicated from vaccination immunological development?

Answer 1

Smallpox 1980

Question 2

What are some examples of successful immunisation campaigns?

Answer 2

Diptheria
Polio
Measles

Question 3

Describe the types of immunological memory;

Answer 3

Genetic

or

Epigenetic

Question 4

Describe immunological memory in terms of genetic causation;

Answer 4

Primary response can result in;

Gene rearrangement
Clonal expansion
Memory population

Rechallenge leads to antigen dependant memory population protection

Question 5

Describe immunological memory in terms of epigenetic causation;

Answer 5

Primary response can result in;

Epigenetic modification of genes encoding immunological and inflammatory products

Rechallenge leads to antigen dependent protection

Question 6

What are the three phases of an immune response?

Answer 6

Pre-existing innate immunity
Induced innate immunity
Induced adaptive immunity

Question 7

What is innate immunity?

Answer 7

Defences that exist to protect the body to prevent infection i.e skin, mucous

or

defences that are activated following an event i.e trauma that may have led to infection. I.e innate immune cells are directed to a skin lesion regardless if infection is present or not, to prevent infection.

Question 8

Describe the evolution of innate immunity;

Answer 8

• Fundamental defensive weapon for multicellular organisms.
• Must be versatile against a spectrum of pathogens
• Molecular mechanisms are highly conserved across species.

Question 9

Describe the nature of the immune response;

Answer 9

If homeostasis is disturbed i.e trauma, cancer, infection then the immune system responds to help restore balance.

Question 10

Describe some pathogens;

Answer 10

Range of shapes and sizes;
worms
protozoa
fungi
bacteria
viruses

Question 11

What is the function of the immune system?

Answer 11

To protect us from pathogens, it is ubiquitous.

Question 12

Why did the immune system evolve?

Answer 12

Pathogens are everywhere in the environment and can reproduce in humans therefore if left unchecked then they can cause permanent damage or be lethal

Question 13

What is the immune system an example of in biology?

Answer 13

An exploratory system mediated by chemical variations (signalling)

Question 14

How does the environment influence pathogen development?

Answer 14

Environmental pressures lead to the selection of traits in pathogen development that favour reproduction in tissues, therefore the immune system must continually evolve to fight the evolving pathogens

Question 15

What are the types of mammalian immune responses?

Answer 15

Innate and adaptive.

These systems are extensively interconnected and form a continuum that is known as the immune response

Question 16

Describe the interplay of adaptive and innate immunity?

Answer 16

innate and adaptive immunity can activate and potentiate one another.

Innate immunity holds pathogens in check until adaptive is ready to function

Question 17

How does innate immunity achieve its response?

Answer 17

non-specifically and broadly specific response

Question 18

How does adaptive immunity function?

Answer 18

Through humoral (antibodies) and cell mediated uniquely specific responses

Question 19

What is an example of innate immunity?

Answer 19

Physical barriers

Question 20

What are the examples of external physical barriers?

Answer 20

Lysozyme in tears
mucous and cilia in bronchi
acids and rapid pH change in gut
Commensals in gut (microflora)
Skin fatty acids and commensals

Question 21

What will largely determine which immune response will be effective?

Answer 21

The site of infection and type of pathogen

i.e intracellular vs extracellular invasive pathogens

Question 22

Give some examples of pathogens that invade differently;

Answer 22

• Influenza must invade cells to reproduce

- Mycobacteria i.e TB can divide extracellularly or in macrophages

Question 23

What is PAMPS?

Answer 23

Pathogen Associated Molecular Recognition Patterns

Question 24

Whats the difference between PAMPS and Antigens

Answer 24

The innate immune system will recognise PAMPS and they are non-specific and found on a number of cells

Antigens are recognised by the adaptive immune system and are pathogen specific

Question 25

Whats are DAMPS?

Answer 25

Damage Associate Molecular Patterns

Question 26

Whats the difference between DAMPS and PAMPS?

Answer 26

Cell damage of death releases DAMPS and can cause inflammation and is often recogised by the same receptors for PAMPS Pathogen or damage can lead to both DAMPS and PAMPS

Question 27

What are the features of the pre-existing non-specific immune response;

Answer 27

- Skin - Mucosal barrier - pH, silivia, proteases etc

Question 28

What are the features of the induced innate immunity broad recognition system;

Answer 28

- Compliment activation - Phagocytosis - Target Cell Lysis - Inflammation

Question 29

What are the features of the adaptive specific immune response?

Answer 29

- B Cells (antibodies) - Th cells (cytokines) - Tc Cells (cytosis)

Question 30

What is a specific immune response?

Answer 30

A specific immune response such as the production of antibodies is known as an adaptive immune response because it results in adaptation of the person to the pathogen Results in lifelong protective immunity

Question 31

How is adaptive immunity distinguished from innate immunity?

Answer 31

Innate immunity is where pathogens are recognised, engulfed, and digested by phagocytic cells (macrophages). These are immediately available as part of the early phase of the host response to pathogens without prior exposure

Question 32

What is part of the innate response?

Answer 32

Pre-existing barriers and induced mechanisms

Question 33

How do innate mechanisms identify cells?

Answer 33

pattern recognition molecules (PRM) identify DAMPS or PAMPS Number of responding cells is always large so no proliferation is required (response is short lived so repeated exposure has similar responses)

Question 34

In an adaptive response, what mechanisms are activated?

Answer 34

All mechanisms are induced

Question 35

Describe adaptive immune cell receptors and ligands

Answer 35

Infinite number of antigen receptor combinations, each is specific. Response is triggered by antigen receptor binding.

Question 36

Describe adaptive immune cells response;

Answer 36

Small number of cells respond and thus must proliferate (these survive), repeated exposure has much larger responses

Question 37

Describe the immune system role in health;

Answer 37

- Clearance of dead cells and damaged cells - Destruction of infectious organisms - Destruction of cancer cells

Question 38

Describe the role of the immune system in disease;p

Answer 38

- Immunodeficiency - Transplant rejection - Autoimmune disease - Hypersensitivity and allergy - Chronic Inflammation

Question 39

Edward Jenner

Answer 39

- Smallpox immunization by Edward Jenner 1796 - First controlled demonstration of the immune response - Took pus from lesions from milk maid who had cow pox. Inculated James Phipps. He did not catch small pox when exposed.

Question 40

Louis Pasteur

Answer 40

- Coined the term of vaccination

Question 41

Elie Metchnikoff

Answer 41

- Characterised the process of phagocytosis by leukocytes - Defined 2 types of phagocytes, the macrophage and the microphage (neutrophils)

Question 42

Jules Hoffman

Answer 42

- Discovered Drosophila with a mutation in the toll gene died because they could not mount an effective defence - Toll was involved in sensing pathogenic microorganisms (a PRR)

Question 43

Bruce Beutler

Answer 43

- Discovered that mice resistant to LPS had a mutation in a gene that was quite similar to the fly toll gene - This TLR was the elusive LPS receptor

Question 44

Ralph Steinman

Answer 44

-Demonstrated that dendritic cells have a unique capacity to activate T cells - The prototypic antigen presenting cell (couples innate and adaptive immunity)