Describe the different aspects of immunology related to medicine

Question 1

Give 5 functional needs of the immune system -

Answer 1

1. Defence against infections
2. Defence against tumours
3. Clearance of dead cells and tumours
4. Immune response
5. Transplants/new proteins

Question 2

Give the key features found in produced/found in epithelial cells, the mouth cavity,tears, the ear, the vagina, urethera

Answer 2

• Epithelial cells
  
  • Defensins
  • Lysozymes
  • Protease inhbitors
• Mouth
  
  • Saliva - – lysozymes and antibiotics
• Tears
  
  • Salty and lysozymes
• Ears
  
  • Cerumen
• Vagina
  
  • Acidic secretions
• Urethera
  
  • Urine

Question 3

Give 4 key features of the skin:

Answer 3

• Epidermins - Dead keratinocytes
• Dermis - Living keratinocytes
• Langerhans cells - APCs
• Sebacous glands = oils (antimicrobial fatty acids)

Question 4

Key 1 features of the upper airway and 1 features of the lower airway

Answer 4

• Upper airway: Mucociliary Escalator
• Lower airway: Surfacants

Question 5

What is the purpose of the mucociliary escalator?

Answer 5

• Mucus (via goblet cells) traps pathogens and cilia wafts the mucus.

Question 6

Give 3 features of the gut which make it a useful external mechanism:

Answer 6

• Low pH
• Enzyme - Pepsin
• Normal flora in gut prevents colonisation of pathogens

Question 7

Give 4 features of both the innate

Answer 7

Question 8

How are forgein substances recognised by the immune system?

Answer 8

• Antigens

Question 9

Adaptive immunity can be split into type what are they?

Answer 9

1. Humoural Immunity
2. Cellular Immunity

Question 10

What is humoural immunity and give the cell type involved?

Answer 10

• Antibody mediated
• Plasma B-cells = antibodies

Question 11

Give 4 functions of extracellular antibodies?

Answer 11

• Activate effector cells
• Aggulutinate pathogens
• Activate complement
• Neautralise toxins

Question 12

What is cellular immunity and what cells/substances does it involve?

Answer 12

• No antibodies
• phagocytes, CTLs, cytokines

Answer 13

1. Pathogen recongition
2. Acute inflammatory response
3. Antigen presentation
4. CD4+ T-cells activate

• Humoral
• Cell mediated

Question 14

Breakdown the immune cell chart (starting with Pluripotent Hematopoietic Stem Cell)

Answer 14

Question 15

Pluripotent Hematopoietic stem cells develop into different types of cells, what are they?

Answer 15

• Myeloid stem cells
• Lymphoid stem cells
• Dendritic cells (through various intermediate stages)

Question 16

Give 2 features of dendritic cells:

Answer 16

• Antigen presentation
• Found in tissues

Question 17

Myeloid stem cells have develop into 3 types of cells, what are they

Answer 17

• RBCs
• Platelets
• Myeloblast stem cells

Question 18

Myeloblast stem cells develop into a precursor cell and then develop into 5 types of cells, what are thet

Answer 18

• Promyelocytes
  
  • Neutrophil
  • Eosiniophil
  • Basophil
  • Monocytes/Macrophages
  • Mast cells

Question 19

Give 2 features of neutrophils:

Answer 19

• Phagocytosis/bactericidal mechanisms
• Contain granules

Question 20

Give 1 feature of eosinophils:

Answer 20

• Killing of parasites and bacteria - secretion of toxic proteins and free radicals

Question 22

Give 2 features of basophils:

Answer 22

• Killing of parasites
• Release histamine

Question 23

• Phagocytosis/bactericidal mechanisms
• Antigen presentation
• Release cytokines
• Can leave the circulatory system

Question 24

Give 3 features of mast cells:

Answer 24

• Killing parasites
• Release histamine
• Found in mucus membranes/connective tissue

Question 25

Lymphoid stem cells develop into 3 types of cells what are they?

Answer 25

* B-cells * T-cells * NKCs

Question 26

Give 3 features of B-cells:

Answer 26

* Orginate and mature in bone marrow/migrate to secondary lympohoid tissue * Express membrane bound antibodies * Differentate into: * Plasma cells * Memory B-cells

Question 27

Give 3 features including the types of T-cells with their function included:

Answer 27

* Orginate in bone marrow, mature in thymus, migrate to secondary lymphoid tissue * Express TCRs * Types 1. CD4+ * TH1 - Activate phagocytes, destruction of extracellular pathogens * TH2 - Activate B-cells, destruction of extracellular pathogens 2. CD8+ - Destruction of host cells infected with virus

Question 28

Give the main function of a NK cell:

Answer 28

* Lyse virally infected cells/ tumour cell

Question 29

Define passive and active immunity:

Answer 29

* **Passive immunity:** Person given antibodies * **Active immunity:** ​Person produces own antibodies

Question 30

What is the primary immune response and give 3 charactherstic features:

Answer 30

* 1st exposure to antigen 1. Less antibodies 2. Slower response (clonal selection and expansion) 3. Memory B-cells

Question 31

What is the secondary immune response and give 2 charactherstic features:

Answer 31

* Exposed to same antigen * Faster response * More antibodies produced

Question 32

What is tolerance?

Answer 32

* When the immune system distinguishes between 'self' and 'non-self antigens'

Question 33

What is autoimmunity, give 2 features and 3 examples with each of their consequences

Answer 33

* Breakdown of tolerance 1. Adaptive immune response attacks self-antigens 2. B/T cells drive chronic inflammtory process * Multiple sclerosis = Neuromuscular dysjunction * Crohns Disease = Poor food absorption * RA = Pain and inflammation

Question 34

What is immunodeficiency, what does it increase the risk of and give the two types:

Answer 34

* Innate/adaptive immune system impaired * Opportunistic infections 1. Primary immunodeficiency (PID) – inherited 2. Secondary immunodeficiency (SID) - Acquired

Question 35

What is hypersensivity, give the types and the reason why it might occur?

Answer 35

* Over-reaction to bengin antigen * Hypersensitivity types (I-IV) * Genetic predisposition = Th cells become more hypesentitive to certain antigens