Immunity

Question 1

What is innate immunity?

Answer 1

The defence system that you are born with
Non-specific
Protects you against all antigens
Barriers that form the first line of defence

Question 2

What is adaptive immunity?

Answer 2

The defence system that builds up as we are exposed progressively to more diseases
Specific/ acquired immunity
Vaccination builds our adaptive immunity
Differentiates between types of pathogens

Question 3

What are chondrocytes?

Answer 3

Cells responsible for cartilage formation

Question 4

What are myocytes?

Answer 4

Cardiac muscle cells (unique to the heart)
They spontaneously depolarise to create a beating rhythm

Question 5

What are swollen lymph nodes a sign of?

Answer 5

That the body is working to defeat infection

Question 6

What is the immune system?

Answer 6

A large network of organs, WBCs, proteins (antibodies) and chemicals
It protects your body from infection, germs, and cell changes that could make you ill

Question 7

What is your immune system made up of?

Answer 7

Special cells, tissues and organs
It’s divided into: innate and adaptive
Each of these two divisions has both humoral (B cells) and cellular (mature T cells) components

Question 8

What is the lymph or lymphatic system?

Answer 8

It is a major part of the immune system
An organ system that complements the circulatory system
Network of vessels through which lymph drains from tissues into the blood

Question 9

What cells make up the immune system? How are they made? What are the different types?

Answer 9

WBCs make up the immune system
they are made in the bone marrow
Granulocytes (neutrophils, basophils, eosinophils)
Monocytes
Lymphocytes (T cells and B cells)

Question 10

What would happen if we were without an immune system?

Answer 10

We would constantly be ill and eventually we would die

Question 11

What department in healthcare do we find a lot of immunosuppressed patients?

Answer 11

Oncology (cancer)
The medications they are on- chemo, radiotherapy, surgery, stem cell and bone marrow transplant)
The cancer itself can weaken and suppress the immune system
Treatments and the cancer lower the number of WBCs and other cells of the immune system

Question 12

What is it called when the immune system doesn’t work in the way that it should?

Answer 12

Immune system disorder/autoimmune disease
=the body’s natural defence mechanisms can’t tell the difference between your own cells and foreign cells
There’s over 80 different types of autoimmune disease
E.g. coeliac disease, rheumatoid arthritis, multiple sclerosis, lupus

Question 13

Name and describe the four ways that the immune system can go wrong

Answer 13

1- Primary immune deficiency
Born with a weak immune system

2- Acquired immune deficiency
Catch a disease or start medication that weakens your immune system

3- Allergic reaction (anaphylaxis)
Have an immune system that is too active

4- Autoimmune disease
Have an immune system that turns against you

Question 14

What is the case of ‘the boy in the bubble’?

Answer 14

David Vetter
Born with SCID- Severe Compromised Immune Deficiency
SCID is one of the most sever types of immunodeficiency disease
Born in 1971 when the only cure for SCID was a bone marrow transplant from an exact donor match, but in David’s family there was no exact donor match
Died at age 12 after failed bone marrow transplant operation
In simple, he had no immune system so his whole body needed protecting by a suit (bubble)

Question 15

Describe Severe Combined Immunodeficiency (SCID)

Answer 15

Rare genetic disorder
Caused by the disturbed development of functional T cells and B cells (from rare genetic mutations)
Defective antibody response
Two types of antibody response:
-direct involvement with B lymphocytes
-improper B lymphocytes activation due to non-functional helper T cells
So, because if the genetic defect the adaptive immune system holds impaired T and B cells
Most sever type of primary immune deficiency is SCID
Nine known gene mutations can cause SCID

Question 16

How do we diagnose SCID?

Answer 16

In early infancy
Babies with SCID tend to seem well at birth- protection from remaining antibodies from mother
After three to six months- first signs of SCID start to show after mothers antibodies wear off
Symptoms- failure to thrive, low weight, repeated infections feeding problems
Go to GP or A&E, but commonly misdiagnosed

Screening tests!
Removes potential for misdiagnosis
Detects low lymphocyte count in the blood
Newborn ‘heel prick test’- blood sent off for lots of testing after birth

Question 17

How do we treat SCID?

Answer 17

Main treatment for SCID babies- done at GOSH or Newcastle

Immunoglobulin replacement therapy (acquired from pool of live donors)
Blood, platelet or plasma transfusions
Bone marrow (stem cell) transplant- most effective!
You receive the healthy stem cells from matched donor (normally healthy sibling)
New cells then rebuild the damaged immune system
Full recovery/cure now possible (lots of orig reps over the last 40 years)

Question 18

How do certain medicines weaken the immune system? What phrase describes this?

Answer 18

Temporary Acquired Immune Deficiencies
Immune system is weakened by:
Certain medications- e.g. chemotherapy or cancer drugs, drugs following organ transplants, immunosuppressants (on for life)
Infections- e.g. flu and measles weaken immune system for a short period (when you get one virus, it weakens your immune system and makes you more susceptible to catching something else at the same time)
Smoking, alcohol and poor nutrition

Question 19

What is HIV?

Answer 19

Human Immunodeficiency Virus
=a virus that attacks the body’s immune system and over time causes acquired immunodeficiency syndrome

Question 20

How is HIV related to AIDS?

Answer 20

If HIV isn’t treated then it can lead to AIDS (Acquired Immunodeficiency Syndrome)
HIV- the virus
AIDS- the disease
It is the AIDS that will eventually kill you. E.g. Prince died from pneumonia as a result of his AIDS that he developed from HIV

Pandemic in the 1980s
Came from monkeys then spread

Question 21

Name and describe some symptoms of HIV

Answer 21

Swollen lymph nodes
Night sweats
Mouth ulcers
Fatigue
Chills
Muscle aches
Rash
Fever

Some people have flu-like symptoms after 2-4 weeks (acute HIV)
These symptoms may last for a few days or several weeks

Easily dismissed as it mimics the symptoms of other typical viral disorders

Question 22

What cells does HIV attack?

Answer 22

CD4 cells (T-cells)
A CD4 count is conducted in people with HIV to check the health of their immune system

Question 23

Name the three stages of HIV

Answer 23

1- acute
2- chronic
3- AIDS

Patients will progress through these three stages without any treatment for their HIV

Question 24

Describe the first stage of HIV

Answer 24

ACUTE
Also known as ‘seroconversion illness’
So mild it is sometimes passed without being noticed (or mistaken for the flu)
Most infectious
Infection rapidly multiplies and spreads
Virus attacks and destroys CD4 cells

Question 25

Describe the second stage of HIV

Answer 25

CHRONIC
Asymptomatic/clinical latency
Don’t often feel any symptoms and can last for a length of years
Can transmit HIV in this stage
Lots of HIV cells, not many CD4 cells
Continues to multiply at low level
If medicated, it’ll never reach stage 3
Infects new cells affecting ability for for immune system to fight illness

Question 26

Describe the third stage of HIV

Answer 26

AIDS
Risk developing infections that the progressively weakened immune system can’t fight
Final and most severe stage
Unable to fight it once it reaches stage 3
Survival= approx 3 years
AIDS defining illnesses: cancers, TB, pneumonia

Question 27

What kind of medicines are used to treat HIV? Briefly describe how they work

Answer 27

Antiretroviral medicines

Medicines work by:
Stop the virus replicating in the body
Allows immune system to repair
Stops further damage to the immune system
Slowing or preventing progression of the disease
Nowadays, progression to stage 3 HIV is much less common due to pharmacological advances

Question 28

Describe how Antiretroviral Therapy (ART) works

Answer 28

Involves taking a combination of HIV medicines
Aim= reduce a persons viral load to an undetectable level

Treatment initiated-
combination of 2 ‘nucleoside reverse transcriptase inhibitors’ (NRTIs)
plus either: ‘integrase inhibitor’ (INI) or a ‘boosted protease inhibitor’ (PI)

Outcomes-
People with HIV are normally able to maintain an undetectable viral load
They therefore have effectively no risk of transmitting HIV to their HIV-negative sexual partners
However…
- there is still a POTENTIAL risk, so they will continue to be regularly checked
- there is a risk to unborn babies

Question 29

Describe some similarities between HIV and coronavirus

Answer 29

Both have:
-RNA viral genome
-nucleocapsid
-surface spikes/ glycoproteins
-viral envelopes

Differences:
-HIV has reverse transcriptase (RT) to convert its RNA into viral DNA

Question 30

Explain the social stigma surrounding HIV

Answer 30

-Stigma is STILL evident surrounding HIV, not so much as it used to though
-Generational- people (especially older generations) still don’t fully understand it
-Remains linked or other discriminations, e.g. racism, homophobia, sexism, transphobia
-Cyclical relationship (between stigma and HIV)= people who experience stigma are marginalised and made even more vulnerable- downward spiral!

Question 31

Where and why do we see an overactive immune system?

Answer 31

From genetic origin
Body overreacts to things in the environment that are usually harmless- ALLERGENS
Allergic reaction= the most common example of an over reactive immune system
E.g. asthma, eczema, hay fever

Question 32

Name the three most common autoimmune diseases

Answer 32

Type 1 diabetes
Rheumatoid arthritis
Lupus

Question 33

What happens in type 1 diabetes?

Answer 33

The immune system attacks the cells in the pancreas that make insulin
Insulin removes sugar from the blood that is used as energy

Question 34

What happens in Rheumatoid Arthritis?

Answer 34

A type of arthritis that causes swelling, pain, stiffness and deformities of the joints
Usually effects the hands, feet and wrists
May be periods where symptoms become worse- flare-ups or flares
Flares are difficult to predict
It’s possible to minimise the number of flares and prevent long-term damage with medication
Auto-antibody called rheumatoid factor is in the blood of some people with rheumatoid arthritis
Methotrexate means regular blood testing is needed
Long-term condition

Question 35

What happens in lupus?

Answer 35

A disease that attacks the body tissues including the lungs, kidneys and skin
Many types of auto-antibodies are found in the blood of people with lupus
E.g. Selena Gomez had a kidney transplant due to her lupus

Question 36

Describe symptoms of Rheumatoid Arthritis

Answer 36

Joint pain
Stiffness
Lining of joints become inflamed
Joints swell, get hot and tender

Question 37

Describe how we treat Rheumatoid Arthritis

Answer 37

Aim of treatment: reducing inflammation, relieve pain, prevent stiffness, slow down joint damage
No cure
‘Disease-Modifying Anti-Rheumatic’ drugs (DMARD) e.g. methotrexate
Methotrexate- first line of treatment for RA, often used with another DMARD and short course of steroids (corticosteroids) to relieve any pain

Question 38

Outline the physiological process of active immunity

Answer 38

Resistance to disease through creation of antibodies by the immune system
Requires a process of training immune cells to recognise and counteract foreign bodies

Foreign body enters organism
Starts to carry out damage via its reproductive activities
Damage being done to cells begins to release a signal to immune cells that something is wrong
Immune cells surround the foreign body and digest them to remove them from the organism
At the same time the immune system learns which proteins are present on the invaders and prepares antibodies to encapsulate them
Original infection is cleared out and the memory is retained- ‘immunological memory’
Next time it invades it’ll automatically bind to the protein- naturally acquired immunity

Question 39

Outline the physiological process of passive immunity

Answer 39

When we are protected from a pathogen by immunity gained by someone else
Short-lived as antibodies are not continually replenished

Occurs in two ways:
MATERNALLY
-placenta and circulation- blood delivers nourishment to the foetus, antibodies circulate with the blood, helps combat virus exposure immediately after birth, baby’s antibody levels reflect that if the mother
-breast milk- colostrum (protein rich breast milk in first few days) contains higher levels of antibodies that protect the intestinal surface, IgA immunoglobulin, as time continues following birth the milk gets less nutritionally dense, helps baby’s immune system to develop its own strength
IMMUNOGLOBULIN TREATMENTS
-antibodies can be obtained from animals, other people, or synthesised in a lab to treat other people at risk of infections
E.g. babies born to women with Hep B are vaccinated with prepared antibodies to prevent them from also being infected with Hep B

Question 40

List the vaccinations given to the neonate

Answer 40

2, 3 AND 4 MONTHS
Diphtheria, tetanus, polio, whooping cough, rotavirus, pneumococcal disease, haemophilus B, Men C
12 AND 13 MONTHS
Measles, mumps, rubella, pneumococcal disease, haemophilus B, Men C

Question 41

When are the different childhood vaccinations given?

Answer 41

2-10 YEARS
Flu vaccination given or offered (every year)

3 YEARS
MMR (second dose), 4-in-1 pre-school booster,

12-13 YEARS
HPV Vaccination

14 YEARS
3-in-1 teenage booster, MenACWY