Intro to Pathology + Defence Cells

Question 1

What is immunology

Answer 1

The study of the immune system

Question 2

What is pathology

Answer 2

The study of the causes/effects of diseases

Question 3

What is Aetiology

Answer 3

The cause, set of causes, or manner of causation of a disease or condition

Question 4

What is morphology

Answer 4

The phenotypic changes associated with a disease

Question 5

What is pathogenisis

Answer 5

Progressive changes as disease develops

Question 6

What is sequalae

Answer 6

What happens next? Can involve intervention

Question 7

Why is immunology and pathology needed

Answer 7

To make the correct diagnosis​

To give the correct treatment​

To understand systemic diseases ​

To make appropriate referrals​

To advise and educate patients​

Question 8

What is the aetiology, morphology, pathogenesis and sequelae of oral cancer

Answer 8

Aetiology – excessive alcohol/tobacco consumption (increased susceptibility)​

Morphology – carcinoma formation​

Pathogenesis – Processes of hyperplasia, dysplasia, neoplasia ​

Sequelae – Radiotherapy, surgery, patient advice​

Question 9

Periodontitis (AMPS)

Answer 9

Aetiology – bacterial origin (plaque)​

Morphology – gingival tissue inflammation, tooth loss​

Pathogenesis – bacterial protease activity, elevated pro-inflammatory response in gingivae​

Sequelae – physical debridement of plaque, removal of infected tissue, patient advice ​

Question 10

Rheumatoid Arthritis (AMPS)

Answer 10

Aetiology – Environmental, genetic (hereditary), other diseases​

Morphology – Joint inflammation​

Pathogenesis – elevated pro-inflammatory response and osteoclast activity, circulating ACPA (antibodies) ​

Sequelae – NSAIDs, Steroids, treatment of other diseases​

Question 11

What systemic diseases is periodontitis linked to

Answer 11

Diabetes
Rheumatoid Arthritis
Stroke
Alzheimer’s Disease

Question 12

What is the surgical sieve

Answer 12

The importance of the correct diagnosis​

Concept of “surgical sieve” refers to a differential diagnosis in which the clinician must distinguish symptoms of a particular disease or condition from others that present similar clinical features ​

Being able to distinguish between diseases with some similar symptoms

Question 13

What are the 4 main organs of the immune system

Answer 13

Thymus
Bone marrow
Lymph nodes
Spleen

Question 14

What is the largest lymphatic organ in the body

Answer 14

Spleen

Question 15

Where do T-cells mature

Answer 15

Thymus

Question 16

What is the yellow tissue in the centre of the bone which makes white blood cells which become lymphocytes

Answer 16

Bone marrow

Question 17

What is the lymphatic system

Answer 17

The motorway for immune cells to circulate

Links key organs:
-Transports clean fluid back to the blood
-Drains excess fluids from tissues
-Removes ‘debris’ from cells of
body
-Transports fats from digestive system

Question 18

What are the two branches of the immune system

Answer 18

Innate + adaptive

Question 19

What is the difference between the two immune systems

Answer 19

Innate - first line of defence

Adaptive - specific and acquired

Question 20

What is an inflammatory reaction

Answer 20

Reaction aimed to eliminate inciting cause

Question 21

What can cause an inflammatory response

Answer 21

-invading microorganisms
-particulate materials (e.g. dust, prostheses e.g., denture material)​
-altered self cells​
-transformed malignant cells (cancer)​

Question 22

What are the stages of inflammation

Answer 22

Initiation – response to harmful agents​

Progression – containment of harmful agents​

Amplification – modulation of immune response​

Resolution – healing (acute inflammation)​

Question 23

What is the failure to resolve inflammation

Answer 23

Chronic inflammation

Question 24

What are some innate immune cells

Answer 24

monocytes/macrophage
mast cells
neutrophils
NK cells
eosinophils
basophils​

Question 25

Which innate immune cells are lymphoid in origin

Answer 25

Natural Killer cells (NK) Innate immune cells (ILCs)

Question 26

Which innate immune cells are myeloid in origin

Answer 26

Mast cells ​ Monocytes/Macrophages ​ Dendritic cells​ Neutrophils​ Eosinophils and Basophils

Question 27

What is the role of monocytes/macrophages

Answer 27

-Circulate in blood as precursors called monocytes​ -Migrate into tissues and differentiate into macrophages ​ -Early responders to infection or tissue damage​ -Long-lived with multiple functions​ -Phagocytose and present antigen​

Question 28

How do mast cells act

Answer 28

-Granulocytes​ -Early responders to infection or tissue damage​ -Migrate from blood and differentiate in tissues (blood precursors not defined)​ -Protect against pathogens (particularly parasitic worms)​ -Best known for role in allergy

Question 29

What is the purpose of neutrophils

Answer 29

ARGUABLY MOST IMPORTANT -Phagocytic granulocytes​ -Most numerous/important cells in innate immune responses ​ -Circulate in blood and move into tissue when required​ -Contain numerous granules (intracellular vesicles)

Question 30

What are NK cells

Answer 30

Large structures with granules Recognize and kill abnormal cells/tumours/viral infected cells​ Important for ‘holding back’ virus infections until adaptive immunity kicks in​

Question 31

What are ILCs

Answer 31

Innate lymphoid cells (ILCs) are non-cytotoxic members of the NK cell family​ Three subsets – ILC1, ILC2 and ILC3s

Question 32

Why do we have Dendritic cells

Answer 32

-Several types of DCs (e.g., Langerhans cells)​ -Main role is antigen presentation​ -Responsible for bridging innate and adaptive immunity​ -Move from tissues to lymph nodes passing on information​ -Activate T cell and B cells​

Question 33

What are the adaptive immune defence cells

Answer 33

T cells and B cells

Question 34

What is the function of T cells

Answer 34

T cells give rise to cellular immunity​ Evolved to protect against intracellular microbes and to help B cells responses​ Recognize peptides presented by antigen presenting cells through the T Cell Receptor (TCR)​ Diversity in TCR (can respond to numerous antigens): T cell repertoire ​ Checkpoints in place however to ensure T cells only respond to foreign pathogens and not ‘self peptides’​

Question 35

What drives the programming of T cells

Answer 35

DC-T cell interactions

Question 36

What are the different subsets of T cells

Answer 36

T helper cells (CD4+) function to help support other immune cells to fight threats​ -Can be TH1, TH2, TH17, TFH cells​ Cytotoxic T cells (CD8+) destroy our own cells which have become infected (usually virus-related)​ Regulatory T cells (Tregs) regulate or suppress other cells in the immune system​

Question 37

Which cells form a bridge between the adaptive and innate immune system

Answer 37

Dendritic cells

Question 38

What are the subsets of B cells

Answer 38

Plasma cells - great big antibody factories​ Memory B cells - important to mount a quicker antibody response to any subsequent infections​

Question 39

How do B cells work

Answer 39

-Communicate with T cells​ -Have a specific B cell receptor for antigens​ -B cells produce antibodies ​ -B cells are also capable of antigen presentation (to T cells for T cell activation)