innate immunity

Question 1

what is innate immunity?

Answer 1

nonspecific defense mechanisms that come into play immediately or within hours of an antigen’s appearance in the body

Question 2

what are the 5 disease causing agents?

Answer 2

• bacteria
• virus
• protozoa
• fungi
• helminth

Question 3

what 4 antimicrobial peptides present in the mouth act as a barrier to pathogens?

Answer 3

• immunoglobulins (IgA)
• lactoferrin
• lysozyme
• cystatins

Question 4

what type of immune proteins is IgA?

Answer 4

antibody

Question 5

why is IgA different from other antibodies?

Answer 5

it doesn’t require T/B cell interaction

Question 6

how does IgA work?

Answer 6

bins to antigen preventing motility and attachment to muscosal surface

Question 7

what type of receptors are bacteria recognised by?

Answer 7

toll-like receptors and NOD-like receptors

Question 8

which type of receptor are viruses recognised by?

Answer 8

toll-like

Question 9

what type of receptors are fungal pathogens recognised by?

Answer 9

dentin and gluten receptors

Question 10

what are toll-like receptors (TLR)

Answer 10

pattern recognition receptors involved in the innate response

Question 11

what are cytokines?

Answer 11

signalling molecules that coordinate the immune response

Question 12

cytokines are said to be involved in autocrine signalling, what does this mean?

Answer 12

alter the behaviour of the cell by which they are secreted from

Question 13

cytokines are said to be involved in paracrine signalling, what does this mean?

Answer 13

alter behaviour of neighbouring cell

Question 14

cytokines are said to be involved in endocrine signalling, what does this mean?

Answer 14

enter circulation and alter behaviour of distant cells

Question 15

what are chemokines?

Answer 15

small signalling proteins that recruit cells to site of inflammation by chemotaxis

Question 16

what is chemotaxis?

Answer 16

movement of organisms in response to chemical stimuli

Question 17

which two molecules dictate and shape immune response?

Answer 17

chemokines and cytokines

Question 18

what are neutrophils?

Answer 18

most abundant granulocyte and WBC, they engulf and destroy invading pathogens

Question 19

neutrophils are which type of immune cell?

Answer 19

phagocyte

Question 20

neutrophils are attracted to the site of inflammation by which chemical?

Answer 20

IL-8

Question 21

what is the difference between a macrophage and a monocyte?

Answer 21

macrophages are monocytes that reside in tissues instead of blood

Question 22

what is the function of macrophages?

Answer 22

antigen presenting, phagocytose, release antimicrobials and enzymes, clearance of damaged tissues and cells

Question 23

are neutrophils antigen presenting?

Answer 23

No

Question 24

are macrophages antigen presenting?

Answer 24

yes

Question 25

what are granules?

Answer 25

vesicles containing performed mediators (proteinases, antimicrobials, chemical mediators)

Question 26

what is the function of mast cells and what immunological process do they lay a key role in?

Answer 26

allergy- release histamine

Question 27

by which mechanism do mast cells release histamine?

Answer 27

undergoing degranulation

Question 28

what is the function of phagocytes?

Answer 28

breakdown pathogens, remove pathogens from tissue and antigen present

Question 29

describe the process of phagocytosis?

Answer 29

• chemotaxis and adherence of microbe to phagocyte
• phagocyte engulfs and ingests microbe
• phagosome forms (phagocytic vesicle)
• phagosome fuses with lysosome to form phagolysome
• enzymes in lysosome digest the microbe
• indigestible material is held within a residual body which is discharged as waste
• antigen presentation

Question 30

what promotes the transport of immune cells through the endothelial cell wall into tissue ?

Answer 30

adhesion factors

Question 31

what are the 4 enzyme cascade systems?

Answer 31

• complement
• kinin
• coagulation factors
• fibrinolytic system

Question 32

how many plasma and cell proteins are in the complement system?

Answer 32

> 30

Question 33

what is the main function of the complement system?

Answer 33

enhance our immunity

Question 34

there are 3 complement system pathways, what re they?

Answer 34

• classical
• alternative
• lectin

Question 35

how is the classic complement pathway triggered?

Answer 35

antibody attaching to microbe

Question 36

how is the alternative complement pathway triggered?

Answer 36

C3b protein binds directly to microbe

Question 37

how is the lectin complement pathway triggered?

Answer 37

mannose sugar binding lectin

Question 38

all complement system pathways impinge on which enzyme cleaving what molecule?

Answer 38

C3 converts cleaving C3

Question 39

where are the complement proteins mainly synthesised?

Answer 39

liver

Question 40

what is the final product of the complement pathway?

Answer 40

membrane attack complex (MAC)

Question 41

what is the name of the process by which white blood cells can squeeze through tight junctions between endothelial cells into tissues?

Answer 41

diapedesis

Question 42

by what term are complement proteins C3a and C5a better known?

Answer 42

anaphylatoxins

Question 43

what 3 specific signals so CD4 cells require to become activated and differentiate?

Answer 43

signal 1 - peptide antigen (presented by MHC II) interacts with cognate T cell receptor
signal 2 - CD28 interacts with CD80/86 expressed on mature dendritic cells
signal 3 - cytokines