Immunology

Question 1

Where are basophils and eosinophils found and what do they do?

Answer 1

Circulate in blood

Recruited to sites of infection

Question 2

What do mast cells, basophils and eosinophils secrete?

Answer 2

Release chemicals such as histamine, heparin and cytokines

Question 3

What do phagocytise cells do?

Answer 3

Ingest and kill Bactria and fungi

Clear debris from dead/dying tissues

Question 4

Where are neutrophils found and what do they do?

Answer 4

Circulate freely in blood

Rapidly recruited into inflamed and infected tissues

Question 5

What do monocytes/macrophages do?

Answer 5

Help limit inflammation
Tissue repair and wound healing
Involves in antigen presentation

Question 6

What do dendritic cells do?

Answer 6

Mature and migrate to secondary lymphoid tissues and stimulate antigen presentation (adaptive immune response)

Question 7

What are NK cells and what do they do?

Answer 7

Large granular lymphocytes
Kill tumour cells and virally infected cels
Kill anitbody bound cells/pathogens

Question 8

What are B cells responsible for?

Answer 8

Production of antibodies

Question 9

What is primary lymphoid tissue the site of?

Answer 9

Leukocyte development

Question 10

What is secondary lymphoid tissue the site of?

Answer 10

Where adaptive immune responses are initiated

Question 11

What is the lymphatic system?

Answer 11

System of vessels draining fluid from body tissues

Lymph nodes are initiated regularly along lymph vessels - remove pathogens and antigens from lymph

Question 12

2 mechanisms of common cation in the immune system?

Answer 12

Direct contact

Indirect contact

Question 13

What is the interaction between in direct contact?

Answer 13

Receptor:Ligand interactions

Receptor if immune cell, ligand of pathogen

Question 14

What is indirect contact?

Answer 14

Production and secretion of cytokines

Injured tissue cells and activated immune cells can produce and secrete cytokines

Question 15

What are cytokines?

Answer 15

Diverse collection of small proteins and peptides produced in response to infection

Question 16

What is the general function of cytokines?

Answer 16

Coordinate immune system by ,ovulating behaviour of cells

Question 17

Examples of cytokines?

Answer 17

Interferons
TNF
Chemotherapy
Interleukins

Question 18

Functions of interferons

Answer 18

Antiviral functions

Question 19

Function of TNF

Answer 19

Pro inflammatory

Question 20

Function of chemokines

Answer 20

Control and direct cell migration

Question 21

Local response to infection

Answer 21

Rubor (redness)
Calor (heat)
Tumour (swelling)
Dolor (pain)
Functio laesa (loss of function)

Question 22

3 phases in response to invading pathogens

Answer 22

Recognition
Activation
Effector

Question 23

What happens in regonitiom phase?

Answer 23

PRRs (pattern-recognition receptors)

Pathogen associated mole

Question 24

IgA

Answer 24

2nd most abundant Ig type
Monomeric form - blood
Dimeric - great milk, saliva, tears, mucosal secretions

Question 25

IgD

Answer 25

Extremely low levels in blood | Surface bound = BCR

Question 26

IgE

Answer 26

Extremely low levels normally | Produced in response to parasitic infection and allergic responses

Question 27

IgG

Answer 27

Most abundant Ig in plasma Actively transported across placenta 4 subtypes

Question 28

IgM

Answer 28

Surface bound monomer = BCR 1st Ig type produced in an immune response ( pentamer - present only in plasma/secretions)

Question 29

How are B cells activated?

Answer 29

Encounter with antigen within lymph nodes If signalled by T lymphocytes B cells rapidly proliferate Differentiate

Question 30

Function of antibodies

Answer 30

Identify pathogens Recruit other immune components (complement, phagocytes, NK cells) Neutralise toxins Particularly important in defence against bacteria

Question 31

Defect of haemopoetic stem cells

Answer 31

Reticular dysgenesis

Question 32

Defects of lymphoid precursors

Answer 32

Severe combined immunodeficiency (SCID) | Failure of production of lymphocytes

Question 33

Clinical features of SCID

Answer 33

``` Unwell by 3 months old Persistent diarrhoea Failure to thrive Continuous infections Unusual skin disease Family history of early infant death ```

Question 34

How long does maternal IgG protect baby for?

Answer 34

3 months

Question 35

Most common form of SCID

Answer 35

X-linked SCID Mutation of IL-2 receptor (inability to respond to cytokines)! Produces immature B cells

Question 36

Treatment for SCID

Answer 36

Prophylactic - avoid infections (antibiotics, antifungals, no vaccine) - aggressive treatment of existing infections - antibody replacement (IV immunoglobulin) Definitive - stem cell transplant (sibling) - gene therapy

Question 37

What is DiGeorge syndrome?

Answer 37

``` Chromosomal deletion Congenital heart defects Cleft palate Hypoparathyroidism Psychiatric disorders ```

Question 38

Clinical presentation of DiGeorge syndrome

Answer 38

Funny looking kid - low set folded ears - high forehead - cleft palate, small mouth & jaw - hypocalcaemia - oesophageal atresia - T cell lymphophopenia - congenital heart disease

Question 39

Investigations for DiGeorge syndrome

Answer 39

Absent or decreased T cells Normal or increased B cells Normal NK cell numbers

Question 40

Management of DiGeorge syndrome

Answer 40

Prophylactic antibiotics Aggressive treatment of infection Immunoglobulin replacement T cell function improves with age

Question 41

Disorders of T cell effector function

Answer 41

Cytokines production Cytotoxicity T-B cell communication

Question 42

Infections caused by issues with IL12 gIFN network

Answer 42

TB Atypical mycobacteria BCG infection after immunisation Deep fungal infections (e.g. Aspergillus)

Question 43

Where are mast cells found and what do they do?

Answer 43

Reside in tissues and protect mucosal surfaces

Question 44

Clinical features of common variable immune deficiency

Answer 44

Recurrent bacterial infections Autoimmune disease Granulomatous disease

Question 45

What does CRP show?.

Answer 45

Degree if inflammation

Question 46

Functions of complement

Answer 46

``` Opsonisation Inflammation Chemotaxis Membrane attack complex Clearance of immune complexes ```

Question 47

What is an antigen?

Answer 47

A substance which can cause an adaptive immune response by activating B cells and T cells

Question 48

Where do adaptive immune responses occur?

Answer 48

Secondary lymphoid tissue