Inflammation

Question 1

Inflammatory pathway

Answer 1

Inducers - Sensors - Mediators - Target tissues/cells

Question 2

Inducers

Answer 2

pathogen-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs), other mediators

Question 3

Sensors

Answer 3

macrophages, dendritic cells (both have receptors on surface for PAMPs/DAMPSs), mast cells (secrete mediators)

Question 4

Mediators

Answer 4

soluble molecules

Question 5

Target tissues/cells

Answer 5

blood cells, epithelial cells, organs

Question 6

Phagocyte

Answer 6

cellsthat protect the body by ingesting (phagocytosing) harmful foreign particles,bacteria, and dead ordyingcells

Question 7

Macrophage

Answer 7

leukocytethat engulfs and digests cellular debris, foreign substances,microbes, cancer cells, and anything else that does not have the types of proteins specific to the surface of healthy body cells on its surface in a process calledphagocytosis - releases chemical signal to recruit other cells

Question 8

Neutrophil

Answer 8

most abundant (40% to 75%) type ofleukocyte, formed from stem cells in the bone marrow, short-lived and highly motile, one of the first-responders of inflammatory cells to migrate towards the site of inflammation, pus=dead neutrophils

Question 9

Phagocytosis definition

Answer 9

the internalisation of particulate matter by cells

Question 10

Phagocytosis steps

Answer 10

(prephagocytosis: tissue injury releases chemical signals, blood vessels dilate and allow phagocytes to move across the wall) 1. binding to surface receptor 2. engulfment into phagosome 3. fusion of phagosome with lysosome (in compartments) 4. killing and degredation of bacterium by lysozyme, proteases, acid hydrolases (break hydrogen bonds) and free radicals

Question 11

Necrosis

Answer 11

uncontrolled cell death

Question 12

Apoptosis

Answer 12

controlled cell death

Question 13

Platelets

Answer 13

initiate clotting

Question 14

Mast cells

Answer 14

release mediators (degranulation), kill parasites, role in allergy and anaphylaxis

Question 15

Basophil

Answer 15

leukocyte, release mediators (degranulation), kill parasites and viruses, role in allergy

Question 16

Eosinophil

Answer 16

leukocyte, release mediators (degranulation), kill parasites and viruses, role in allergy and asthma

Question 17

Lymphocyte

Answer 17

leukocyte, slow response, include NK cells, T cells, B cells

Question 18

NK cells

Answer 18

directly kill virally infected cells and tumour cells

Question 19

B cells

Answer 19

recognise whole pathogens, make antibodies, developed in bone marrow

Question 20

T cells

Answer 20

recognise fragments of pathogens bound to MHC molecules on cell surface, developed in thymus - CD8 and CD4

Question 21

CD8 (cytotoxic) T cells

Answer 21

kill infected cells

Question 22

CD4 (helper) T cells

Answer 22

help B cells make antibody or activate macrophages

Question 23

“Naïve” T and B cells

Answer 23

undergo education program to eliminate “self” reactive cells - negative selection

Question 24

Antigen

Answer 24

any substance that causes your immune system to produce antibodies against it

Question 25

Antibody

Answer 25

(aka immunoglobulin) large, Y-shape protein used to identify and neutralize pathogens

Question 26

Lymphatic system

Answer 26

route to return fluid from tissues to blood, transports immune cells, pathogens and antigens from tissues to lymph nodes (activates T and B cells)

Question 27

Chemotaxis

Answer 27

the movement of leukocytes up a gradient of chemicals towards it source

Question 28

Leukocyte pathway

Answer 28

1. Margination (accumulation and adhesion to blood vessel walls at site of injury) 2. Diapedesis (leaving the blood) 3. Chemotaxis 4. Phagocytosis

Question 29

Role of soluble mediators

Answer 29

dilation of blood vessels, increased permeability of blood vessels, activation of endothelium (allow adhesion of leukocytes), chemotaxis, amplification of immune response, resolution of acute inflammation

Question 30

Kinin

Answer 30

any of a group of substances formed in body tissue in response to injury

Question 31

Examples of soluble mediators

Answer 31

plasma cascades, histamine, lipid mediators (prostaglandins, leukotrienes), cytokines

Question 32

Acute inflammation

Answer 32

immediate response, movement of leukocytes, leakage of plasma and soluble mediators, inflammation resolves, compontents: changes in vascular flow, increased vascular permeability, emigration of leukocytes from circulation to injury site

Question 33

Chronic inflammation

Answer 33

long term, tissue destruction w attempts at repair, mononuclear cell infiltration (macrophages, lymphocytes), abnormal repair (fibrosis, angiogenesis)

Question 34

Types of anti-inflammatory drugs

Answer 34

NSAIDs, corticosteroids, biologicals. Note: need for more effective and safer anti-inflammatory drugs

Question 35

NSAIDs

Answer 35

Non-steroidal anti-inflammatory drugs: reduce pain, fever, inflammation, inhibit cyclooxygenase enzymes. Side effects: stomach bleeding, thrombosis/heart attack. Eg. Asprin, Ibuprofen, Celebrex, Vioxx

Question 36

Cyclooxygenase enzymes

Answer 36

catalyze prostaglandin production from arachidonic acid

Question 37

Corticosteroids

Answer 37

Supress inflammation: down-regulate expression of genes involved in inflammation, up-regulate expression of anti-inflammatory proteins. Eg. Dexamethasone, Prednisone

Question 38

Classes of corticosteroids

Answer 38

Glucocorticoids: anti-inflammatory, Mineralocorticoids: control electrolyte/water levels

Question 39

Biologicals

Answer 39

Soluble proteins that block actions of key cytokines or chemokines that drive inflammation. Expensive and can compromise immune system. Eg. Etanercept (anti-TNF), soluble IL-1 Receptor