Defence Cells

Question 1

What is chronic disease?

Answer 1

Chronic disease is caused by a malfunctioning immune system, defence cells might contribute to this malfunctioning

Question 2

What is periodontal disease?

Answer 2

A chronic inflammatory disease

Question 3

What is PD characterised by?

Answer 3

Inflammation of the gums, destruction of the alveolar bone and periodontal ligament

Question 4

What is the initiating factor of PD?

Answer 4

Dental plaque

Question 5

Does removal of plaque resolve PD?

Answer 5

No, as immune malfunction/dysregulation plays a role in PD too

Question 6

What would be seen in a tissue cross section of an adult with PD?

Answer 6

Apical migration of epithelial tissue (towards tooth apex, tip of root), formation of a periodontal pocket (around tooth)

Question 7

Why are cells recruited to epithelial tissues in PD?

Answer 7

In response to biofilm present on tooth surface

Question 8

Where do majority of defence cells originate from?

Answer 8

Bone marrow

Question 9

Where do blood cells originate from?

Answer 9

Haematopoietic stem cells

Question 10

What do haematopoietic stem cells give rise to?

Answer 10

Lymphoid and myeloid

Question 11

What are the myeloid cells?

Answer 11

Macrophage
Eosinophil
Basophil
Neutrophil
Mast cell
Dendritic cell (can also be lymphoid)

Question 12

What are the lymphoid cells?

Answer 12

B cells
T cells
NKC (natural killer cells)

Question 13

What category of WBC are neutrophils?

Answer 13

Granulocytes

Question 14

What do neutrophils do?

Answer 14

Circulate in blood and move into tissue when needed
Bring about phagocytosis
Activate bactericidal mechanisms

Question 15

What do neutrophils contain?

Answer 15

Granules which have degradative enzymes and antimicrobial substances

Question 16

How are macrophages formed?

Answer 16

Monocytes circulate in blood are precursors

They migrate into tissues and differentiate into macrophages

Question 17

What cells are early responders to infection or tissue damage?

Answer 17

Macrophages, mast cells

Question 18

What do macrophages do?

Answer 18

Phagocytosis
Activate bactericidal mechanisms
Antigen presentation

Question 19

Which cells have a major role in immune responses?

Answer 19

Macrophages

Question 20

What catagory of WBC are mast cells?

Answer 20

Granulocytes

Question 21

What do mast cells do?

Answer 21

Migrate from blood and differentiate in tissues

Protect against pathogens- particularly parasitic worms

Question 22

How do mast cells function?

Answer 22

By releasing granules containing histamine and active agents

Question 23

What immune reaction are mast cells involved in?

Answer 23

Allergy

Question 24

What category of WBC are eosinophils?

Answer 24

Granulocytes

Question 25

What do eosinophils contain?

Answer 25

Granules containing degradative enzymes and antimicrobials

Question 26

What is the defensive role of eosinophils?

Answer 26

Defence against parasites, larger than neutrophils so can ingest larger threats

Question 27

What is the function of eosinophils?

Answer 27

Killing antibody coated parasites

Question 28

Are eosinophils involved in allergy?

Answer 28

Yes

Question 29

What category of WBC are basophils?

Answer 29

Granulocytes

Question 30

What is the function of basophils?

Answer 30

To promote allergic responses | Augmentation of anti-parasitic immunity

Question 31

What is the function of dendritic cells?

Answer 31

Antigen presentation

Question 32

What do dendritic cells form a bridge between?

Answer 32

Innate and adaptive immune responses

Question 33

How do dendritic cells appear?

Answer 33

As long, fingerlike processes

Question 34

What do dendritic cells do?

Answer 34

Migrate from blood to tissue Phagacytose organisms Can ingest extracellular fluid- macropinocytosis Degrade pathogens

Question 35

What is the major function of dendritic cells?

Answer 35

To present the antigen directly to T cells

Question 36

Where do t cells mature?

Answer 36

Thymus

Question 37

What do t cells give rise to?

Answer 37

Cellular immunity

Question 38

How do T cells recognise peptides presented by antigen presenting cells?

Answer 38

Through T cell receptor TCR

Question 39

What are the two types of T cell?

Answer 39

CD4+ or CD8+

Question 40

How are CD molecules named?

Answer 40

According to cluster differentiation (CD!!) glycoprotein on cell surface

Question 41

What are CD molecules involved in?

Answer 41

Antigen presentation

Question 42

What are MHC's?

Answer 42

Major histocompatability complexes, class I or II. They are the 'flag pole' that attaches antigen to surface of cell for presentation, which is then recognised by various receptors on T or B cells.

Question 43

what do T cell CD8+ cells interact with?

Answer 43

MHC class I

Question 44

What do T cell CD4+ cells interact with?

Answer 44

MHC class II

Question 45

What are CD8+ cells?

Answer 45

Cytotoxic | Destroy infected self cells

Question 46

What are CD4+ cells?

Answer 46

Play a central role in immune protection | Numerous subsets which modulate immune response depending on pathogenic threat

Question 47

How do CD4+ cells come about?

Answer 47

Start life as naive T cell 3 signals for activation of T cells 3rd signal determines fate of naive T cell

Question 48

What are the CD4+ subsets?

Answer 48

``` TH1 TH2 TH17 TFH THreg ```

Question 49

What does TH1 do?

Answer 49

Supportes macrophages to destroy intracellular microbes

Question 50

What does TH2 do?

Answer 50

Produces cytokines which activate mast cells and eosinophils | Promote barrier immunity at mucosal surfaces

Question 51

What does TH17 do?

Answer 51

Secrete IL-17 family cytokines, specific role in supporting immune cell function

Question 52

What does TFH do?

Answer 52

Induce specific B cell response, antibody responses

Question 53

What does THreg do?

Answer 53

Switches T cell response off to prevent autoimmunity

Question 54

Where do B cells mature?

Answer 54

In bone marrow

Question 55

What does diversity in B cell receptor mean?

Answer 55

That B cells can respond to numerous antigens

Question 56

What do B cells do?

Answer 56

When activated they turn into plasma cells, which are the cells that produce antibodies. So B cells produce antibodies

Question 57

What are T and B cells mainly involved in?

Answer 57

Adaptive immunity- memory and specificity

Question 58

What are natural killer cells?

Answer 58

Considered part of innate immunity

Question 59

What is natural killer cell function?

Answer 59

Involved in destruction of virus infected cells, can recognise and kill abnormal cells