Introduction to immunity and pathology

Question 1

Immunology definition

Answer 1

the study of the immune system

Question 2

Pathology definition

Answer 2

the study of the causes/effects of disease

Question 3

Why is immunology and pathology important?

Answer 3

to provide the correct diagnosis, treatment, referrals and patient education/advice

Question 4

Aetiology definition

Answer 4

causes of a disease or condition (pathology)

Question 5

Possible aetiology of a disease/condition

Answer 5

genetic (e.g hereditary) and/or environmental (e.g. diet, alcohol, smoking)

Question 6

Pathogenesis definition

Answer 6

Progressive changes as disease develops, involving morphological cellular changes (macro/microscopic)

Question 7

Sequalae definition

Answer 7

The next steps which often involves intervention.

Question 8

Examples of two common oral pathologies

Answer 8

oral cancer (usually oral squamous cell carcinoma), periodontitis

Question 9

What is the aetiology of oral cancer?

Answer 9

excessive alcohol/tobacco consumption increases susceptibility (environmental), can also be genetic

Question 10

What is the pathogenesis of oral cancer?

Answer 10

processes of hyperplasia, dysplasia, neoplasia

Question 11

What is the sequalae for oral cancer?

Answer 11

Radiotherapy, surgery, patient advice

Question 12

What is the aetiology for periodontitis?

Answer 12

Bacteria origin (plaque)

Question 13

What is the pathogenesis of periodontitis?

Answer 13

inflammation in gingival tissues, bone resorption

Question 14

What is the sequalae in periodontitis?

Answer 14

physical debridement of plaque, removal of infected tissue, patient advice

Question 15

What systemic diseases is periodontitis linked to?

Answer 15

Diabetes, rheumatoid arthritis, respiratory disease, stroke, Alzheimer’s disease

Question 16

What is the aetiology of rheumatoid arthritis?

Answer 16

environmental and/or genetic factors, other diseases (e.g. periodontitis)

Question 17

What is the pathogenesis of rheumatoid arthritis?

Answer 17

joint inflammation, increased osteoclast activity, circulating ACPA (antibodies)

Question 18

What is the sequelae of rheumatoid arthritis?

Answer 18

NSAIDs (medicines that relieve pain and inflammation), steroids, treatment of other diseases (e.g. periodontitis treatment to ease RA)

Question 19

Examples of cells that make up the immune system

Answer 19

leukocytes, lymphocytes, epithelial cells, endothelial cells

Question 20

How are the organs and cells of the immune system connected?

Answer 20

Lymphatic system (allows immune cells - lymphocytes and leucocytes - to circulate)

Question 21

What makes up the lymphatic system?

Answer 21

Lymph, lymphatic vessels, lymphoid organs, lymphoid tissues, immune cells

Question 22

What are the primary sites of the lymphatic system?

Answer 22

The sites where immune cells are created and mature

Question 23

What are the secondary sites of the lymphatic system?

Answer 23

The sites where immune cells are stored and proliferate

Question 24

What is lymph?

Answer 24

A clear, colourless fluid that circulates through the lymphatic system

Question 25

Where does lymph originate?

Answer 25

From excess interstitial fluid that surrounds the body's cells

Question 26

What is lymph made up of?

Answer 26

>90% water, proteins (antibodies), immune cells, waste products (CO2 and urea)

Question 27

What are the lymphoid organs?

Answer 27

Lymphatic vessels, lymph nodes, thymus, bone marrow, spleen, specialised tissues (e.g. tonsils, adenoid)

Question 28

Name the primary lymphoid organs

Answer 28

thymus and bone marrow

Question 29

Name the secondary lymphoid organs

Answer 29

lymph nodes, spleen, specialised lymphoid tissues (e.g. tonsils, adenoid)

Question 30

Location of thymus

Answer 30

mediastinum (central in chest, posterior to lungs)

Question 31

How does thymus size differ from a newborn to an adult?

Answer 31

Thymus decreases in size

Question 32

Function of thymus

Answer 32

Site of T cell maturation and education (T for thymus)

Question 33

What colour bone marrow produces haemopoietic stem cells?

Answer 33

red bone marrow

Question 34

Function of haemopoietic stem cells produced in the red marrow

Answer 34

Haemopoietic stem cells differentiate into different types of immune cells

Question 35

Function of spleen

Answer 35

Secondary lymphoid organ involved in blood filtration system

Question 36

Function of lymph nodes

Answer 36

Secondary lymphoid organ involved in lymph filtration system

Question 37

Function of specialised lymphoid tissues

Answer 37

Immunological barriers, mucosal surfaces (e.g. tonsils, adenoids, parts of gut)

Question 38

What are the two branches of the immune system?

Answer 38

innate and adaptive immunity

Question 39

What is innate immunity?

Answer 39

the first line of non-specific defence

Question 40

What is adaptive immunity?

Answer 40

specific and acquired defence involving B and T cells

Question 41

Which branch of the immune system is involved in creating immunological memory?

Answer 41

Adaptive immunity (specific receptors on B and T cells)

Question 42

What is humoral?

Answer 42

'Liquid/fluid' - proteins produced by the cellular components

Question 43

What are the innate immune cells?

Answer 43

leukocytes - e.g. monocytes/macrophages, mast cells, neutrophils, NK cells, eosinophils, basophils

Question 44

What are the adaptive immunity cells?

Answer 44

Lymphocytes - B and T cells

Question 45

Examples of non-professional immune cells

Answer 45

endothelial/epithelial cells (not from bone marrow stem cells)

Question 46

Which type of immunity is present from birth?

Answer 46

innate immunity

Question 47

Which type of immunity is active in the first 1-4 days of exposure to the pathogen?

Answer 47

innate immunity

Question 48

Which cells contribute to innate immunity, alongside the leukocytes?

Answer 48

non-professional immune cells - epithelial cells, endothelial cells, fibro blasts (e.g. mucous membrane)

Question 49

Does innate immunity provide lasting protection?

Answer 49

No - no memory

Question 50

Which type of immunity do vaccines utilise?

Answer 50

Adapted immunity

Question 51

At which day after pathogen exposure is adaptive immunity active?

Answer 51

day 4-10

Question 52

What are the two types of responses that make up adaptive immunity?

Answer 52

Cell-mediated and humoral (antibody) responses

Question 53

Which cells are involved in cell-mediated immunity?

Answer 53

T cells drive cell-mediated immunity with the activation of macrophages, NK cells, epithelial cells

Question 54

Which cells drive humoral immunity?

Answer 54

B cells (produce antibodies)

Question 55

What cells are defence cells?

Answer 55

Professional (innate/leucocytes and adaptive/lymphocytes) and non-professional (epithelial, endothelial, fibroblasts) immune cells

Question 56

Function of macrophages

Answer 56

phagocytose and present antigen - multiple functions (M1 and M2 macrophages)

Question 57

Difference between macrophages and monocytes?

Answer 57

Macrophages migrate and differentiate into tissues whereas monocytes circulate in blood.

Question 58

Which defence cells are granulocytes?

Answer 58

Mast cells, neutrophils, basophils, eosinophils, NK cells

Question 59

What are mast cells?

Answer 59

Granulocytes that respond to inflammation and protect against pathogens by degranulation (histamine). They migrate from blood and differentiate in tissues.

Question 60

What is histamine?

Answer 60

A type of chemical mediator found in granules

Question 61

Which defence cells are involved in allergies?

Answer 61

mast cells, eosinophils, basophils

Question 62

What are neutrophils?

Answer 62

phagocytic granulocytes that are the most numerous and important cells in innate immune response. Circulate in blood and move into tissue when required.

Question 63

What process do neutrophils undergo?

Answer 63

NETosis via degranulation

Question 64

What is NETosis?

Answer 64

the production of neutrophil extracellular traps that encapsulate pathogens

Question 65

What are basophils and eosinophils?

Answer 65

granulocytes that undergo degranulation and are both involved in allergy. Have a similar structure to neutrophils and a similar function to mast cells.

Question 66

Which defence cell plays a major role in anti-parasitic immunity?

Answer 66

eosinophils

Question 67

What are NK cells?

Answer 67

Natural killer cells are large granulocytes that have long cellular projections (detection). Important in killing host cells.

Question 68

Which host cells would be destroyed by NK cells?

Answer 68

Cancerous cells, viral infected cells, microorganisms

Question 69

Which defence cell bridges innate and adaptive immunity?

Answer 69

Dendritic cells (APC)

Question 70

Function of dendritic cells

Answer 70

phagocytosis and antigen presentation. Also move from tissues to lymph nodes to activate B and T cells.

Question 71

What is the name of the type of dendritic cell found in the skin?

Answer 71

Langerhans cells

Question 72

Where do T cells mature?

Answer 72

Thymus

Question 73

Location of T cells

Answer 73

circulate in the lymph and are stored in lymph nodes

Question 74

Which defence cell drives cellular immunity (branch of adaptive immunity)?

Answer 74

T cells

Question 75

Function of T cells

Answer 75

recognise antigens (peptides). there are lots of subsets of T cells that have different functions.

Question 76

Where do B cells mature?

Answer 76

Bone marrow (red)

Question 77

Where are B cells located?

Answer 77

Lymph and lymph nodes

Question 78

Which defence cells drive humoral immunity?

Answer 78

B cells

Question 79

Function of B cells

Answer 79

produce antibodies (drive humoral immunity), also capable of antigen presentation for T cell activation

Question 80

How many subsets of B cells are there?

Answer 80

2 subsets

Question 81

Function of non-professional immune cells?

Answer 81

Epithelial, endothelial cells and fibroblasts play a role in inflammatory (immune) responses