51-Inflammation and Phagocytosis

Question 1

what is the hallmark of the activation of the innate immune response

Answer 1

inflammation

Question 2

how is inflammation activated

Answer 2

release of inflammatory mediators

Question 3

what are the signs of inflammation

Answer 3

redness
heat
swelling
pain
loss of function

Question 4

what are the functions of inflammation

Answer 4

recruit immune cell
enhance immune cell function
limit spread of infection
promote tissue repair

Question 5

what are the steps of inflammation

Answer 5

1-tissue damage causes release of inflammatory molecules because sentinel cells and pattern recognition receptors recognize pathogens
2-vasodilation to increase blood flow to damaged area and increase immune cells
3-blood clots localize the infection, abscess forms
4-promote wound healing

Question 6

what does vasodilation cause during inflammation?

Answer 6

redness, swelling, pain, loss of function

Question 7

how does fever response help infection?

Answer 7

decrease viability of pathogen

increase immune cell function

Question 8

what are the sentinel cells

Answer 8

macrophages and mast cells

Question 9

what do sentinel cells do

Answer 9

recognize pathogens and release inflammatory molecules

Question 10

what are the inflammatory molecules and what do they do?

Answer 10

cytokines, chemokines, lipid mediators
1-vasodilation of blood vessels
2-recruit immune cells
3-activate immune cells

Question 11

where are mast cells found

Answer 11

epithelial and mucosal layers

Question 12

where are macrophages found

Answer 12

everywhere in the body

Question 13

what do cytokines released by sentinel cells do

Answer 13

TNF, IL-1, IL-6, IL-12, IFN-gamma

enhance immune cell function, regulate vascular permeability

Question 14

what are the important cytokines released by sentinel cells

Answer 14

TNF, IL-1, IL-6

Question 15

what do lipid mediators do

Answer 15

alter vascular permeability, vasodilation, contraction of smooth muscle

Question 16

what does histamine do

Answer 16

increase vascular permeability, increase vasodilation, increase pain responses

Question 17

how does recruitment infection work

Answer 17

1-TNF and IL-1 are released from mast and macrophages to alter blood vessel endothelium. decreased cell to cell contacts and increase permeability
2- E and P selectin on vessel bind selectin ligand on cell to slow it down and roll
3-chemokine on vessel bind chemokine ligand on cell to activate integrin
4-integrin on immune cell bind integrin ligand on vessel (iCAM-1) to stop the cell
5-cell moves across vessel to infection

Question 18

How does TNF work systemically

Answer 18

stimulate adipose and muscle for stored energy (immune system requires lots of energy)

Question 19

How does the liver promote immunity systemically

Answer 19

release acute phase reactants after IL-1 and IL-6 stimulate

Question 20

what do acute phase reactants do?

Answer 20

immunity and wound healing

Question 21

what is C reactive proteins

Answer 21

an acute phase reactant used as a clinical marker for inflammation

Question 22

when is inflammation good?

Answer 22

localized

Question 23

when is inflammation bad?

Answer 23

systemically

Question 24

systemic inflammation can lead to what?

Answer 24

widespread vasodilation, low blood pressure, edema, collapse of blood vessels and organ failure and death

Question 25

high fever can lead to what

Answer 25

respiratory and CV disease, fatal

Question 26

what is the positive control feedback for inflammation

Answer 26

TNF and IL-1

Question 27

what are the negative feedback for inflammation

Answer 27

IL-1Ra to inhibit IL-1 soluble TNF receptors immune suppressants cytokines TGF-B and IL-10

Question 28

what is DIRA and symptoms

Answer 28

lack of IL-1Ra, skin pustules, widening and lesions of bones

Question 29

treatment for DIRA

Answer 29

anakinra- recombinant IL-1Ra

Question 30

what is phaocytosis

Answer 30

ingestion and killing of microbial pathogens

Question 31

what is the purpose of phagocytosis

Answer 31

1-remove and kill pathogens 2-induce inflammation 3-activation of adaptive immune response

Question 32

what are the cells involved in phagocytosis

Answer 32

neutrophils, macrophages, dendritic cells

Question 33

characteristics of neutrophils

Answer 33

most abundant phagocytic cell short lived (4-8 bacteria), rapidly migrate to infection phagocytose and kill microbe die by apoptosis quickly and leave behind remnants (pus)

Question 34

characteristics of macrophages

Answer 34

derived from monocytes long lived found in tissues (Kaupffer, microglia, skin) phagocytose and kill pathogens, induce inflammation, wound healing

Question 35

characteristics of dendritic cells

Answer 35

derived from monocytes reside in tissues process pathogens and present to t cells to activate adaptive response, wound healing

Question 36

when are macrophages used during infection

Answer 36

very early (sentinel), sense infection and induce inflammation, and later phases for wound healing

Question 37

when are neutrophils used during infection

Answer 37

early phases

Question 38

steps in phagocytosis

Answer 38

``` 1-migration/chemotaxis to infection 2-ingestion of pathogen into phagosome 3-fusion with lysosome granules to form phagolysosome 4-degradation of pathogen 5-release of debris ```

Question 39

what are the 2 cell surface proteins and what do they do

Answer 39

Innate immune receptors opsonin receptors adhere to pathogens and engulf them

Question 40

what do the innate immune receptors do?

Answer 40

bind directly to the pathogen ( mannose receptor binding mannose) to engulf pathogen

Question 41

what do the opsonin receptors do

Answer 41

bind to host protein to interact with pathogen (requires intermediate) CR3, CR4, Fc receptors

Question 42

what are the complement receptors and what do they bind to

Answer 42

CR3 and CR4 bind to complement fragments that are bound to the pathogen Fc receptors which bind to antibodies bound to the pathogen

Question 43

how do phagocytic cells engulf apoptotic cells

Answer 43

apoptotic cells have changes in membrane phosphatidyl serine is on the outside of the cell instead of the inside and is recognized by opsonin and innate receptors on macrophages. NON INFLAMMATORY. necrosis is inflammatory

Question 44

what are the 2 types of granules in phagocytes and what do they do

Answer 44

primary and secondary | degrade microbes and apoptotic cells

Question 45

what do primary granules do

Answer 45

resemble lysosomes and contain anti microbial proteins

Question 46

what do secondary granules do

Answer 46

activation of NADPH oxidase that form ROS

Question 47

what is different about the granules in macrophages vs. neutrophils

Answer 47

neutrophils have preformed granules that are functional | macrophages need to be activated by interferon gamma

Question 48

what activates macrophages granules

Answer 48

interferon gamma

Question 49

how does NADPH oxidase complex form

Answer 49

activation of Rac2 by opsonin or innate receptors Rac2 binds gp91 gp91 recruits other subunits to form complex

Question 50

what does the NADPH complex do

Answer 50

use oxygen and NADPH to form free radicals. processed to hydrogen peroxide and hypochlorite

Question 51

how are nitrogen free radicals formed

Answer 51

by phagocytic cells using arginine, oxygen and NADPH

Question 52

what do nitrogen free radicals do

Answer 52

disrupt enzymes or form with more oxygen free radicals to alter tyrosine residues

Question 53

what are the symptoms of leukocyte adhesion deficiency

Answer 53

skin infections without pus, no loss of umbilical cord, recurrent infections. do not form abscesses. poor migration of leukocytes to site of infection

Question 54

how do you treat leukocyte adhesion deficiency

Answer 54

bone marrow transplant

Question 55

what causes leukocyte adhesion deficiency type 1

Answer 55

defect in integrin on cell, cell doesn't stop at infection

Question 56

what causes leukocyte adhesion deficiency type 2

Answer 56

defect in selectin ligands, cell doesn't roll on vessel but it moves too fast past