Download Unit 4 - Immunology and Public Health

Unit 4 Immunology and
Public Health
Unit 4 – Immunology and Public
Health
1. The Immune
System
a)Non-specific
defences
b)Specific cellular
defences
2. Infectious
Diseases and
immunity
a)Transmission and
control
b)Active
Immunisation and
Vaccination and
the evasion of
immune responses
Can you now ….
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describe what is meant by Immune
Surveillance
describe what is meant by Clonal Selection
Theory
describe the specificity of lymphocyte
receptors
describe the roles of 2 types of Tlymphocytes in response to infection
describe the role of B-lymphocytes in
response to infection
describe what is meant by immunological
memory
state the benefits of having memory cells.
describe the role of T lymphocytes in
recognising self and non-self
explain what is meant by an autoimmune
disease in relation to lymphocyte regulation
state what is meant by the term ‘allergy’
and give examples of common allergic
reactions
Quick Questions
1. Describe when a clonal population of
lymphocytes would be produced in the
body?
2. If each lymphocyte can only recognise
one specific antigen, how is it possible
that lymphocytes offer effective
protection against a wide variety of
pathogens?
Quick Questions
1. 2 types of lymphocytes are produced.
Explain the role of the lymphocyte which is
involved in cells self-destructing.
The lymphocyte involved in cell destruction is
the cytotoxic or killer T cell.
It induces apoptosis in infected cells
2. What is produced by B-lymphocytes during
the immune response?
Antibodies specific to the antigen
3. 3. Name 3 possible effects of the protein
produced by B-lymphocytes
Quick Questions
3. Name 3 possible effects of the protein
produced by B-lymphocytes
 Inactivate a pathogen or toxin
Render it more susceptible to
phagocytosis.
Stimulate a response which results in
cell lysis.
Quick Questions
1.Name cell
Q
2.Describe 2
functions
of cell P
as shown
in the
diagram.
3.Name cell
P
Quick Questions
For each statement below state if it
refers to the 1st or 2nd exposure of a
pathogen
a) Larger concentration of antibodies produced
b) Clonal population of lymphocytes occurs
faster
c) Memory cells are produced
d) Immune response is longer
e) Illness occurs
Questions – 12 minutes!
1)
2)
3)
4)
What are the two types of lymphocytes?
Where do T lymphocytes mature?
Why are cytokines released at the site of infection?
What is the name of the proteins found on cell surfaces that
trigger an immune response?
5) Describe clonal selection.
6) a) What is autoimmunity?
b) Give a condition linked to autoimmunity.
7) How does a TC cell lead to the destruction of an infected cell?
8) a) What does an activated B cell produce?
b) How do these molecules bring about destruction of a pathogen?
9) What term is used to describe the first infection of the body by a
pathogen?
10) If the body is re-infected at a later date, what is this known as?
11) Which cells are central to being able to fight off re-infection?
12) How does the immune response to the second infection compare to
the first?
1)
2)
3)
4)
5)
Answers
B and T lymphocytes
The thymus gland
To activate B lymphocytes and phagocytes
Antigens
The binding of a lymphocyte receptor to an antigen activates the
lymphocyte which leads to it dividing producing a clonal population
of lymphocytes.
6) a) An immune response against self antigens by T lymphocytes
b) rheumatoid arthritis / Type 1 diabetes / multiple sclerosis.
7) Induces apoptosis (programmed cell death)
8) a) Specific antibodies that recognise a specific antigen
b) when an antibody-antigen complex is formed the pathogen is
inactivated OR it renders it more susceptible to phagocytosis OR
stimulates a response which results in cell lysis
9) Primary exposure
10) Secondary exposure
11) Memory cells
12) The second response produces a larger concentration of antibodies
and does it faster than the first response
Quick Questions
1. Choose the correct words from the
box below to describe what is meant by
the term allergic reaction
> Under-reacts
> Hyposensitive response
> Over-reacts
> Normally harmful substance
> Hypersensitive response > Normally harmless substance
2. What cell is involved in autoimmune
diseases?
3. Explain the role of this cell in
autoimmune diseases
Questions & ANSWERS
1)
2)
3)
4)
5)
6)
What are the two types of lymphocytes?
– B and T lymphocytes
Where do T lymphocytes mature?
– The thymus gland
Why are cytokines released at the site of infection?
– To activate B lymphocytes and phagocytes
What is the name of the proteins found on cell surfaces that
trigger an immune response?
– Antigens
Describe clonal selection.
– The binding of a lymphocyte receptor to an antigen activates the
lymphocyte which leads to it dividing producing a clonal population
of lymphocytes.
a) What is autoimmunity?
– An immune response against self antigens by T lymphocytes
b) Give a condition linked to autoimmunity.
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rheumatoid arthritis / Type 1 diabetes / multiple sclerosis.
Questions & Answers
7) How does a TC cell lead to the destruction of an infected cell?
Induces apoptosis (programmed cell death)
8) a) What does an activated B cell produce?
Specific antibodies that recognise a specific antigen
b) How do these molecules bring about destruction of a pathogen?
when an antibody-antigen complex is formed the pathogen is
inactivated OR it renders it more susceptible to phagocytosis OR
stimulates a response which results in cell lysis
9) What term is used to describe the first infection of the body by a
pathogen?
Primary exposure
10) If the body is re-infected at a later date, what is this known as?
Secondary exposure
11) Which cells are central to being able to fight off re-infection?
Memory cells
12) How does the immune response to the second infection compare to the
first?
The second response produces a larger concentration of antibodies and
does it faster than the first response