Innate immunity

Question 1

Is the innate immunity specific/nonspecific?

Answer 1

nonspecific

Question 2

What are the 3 components of the innate immunity?

Answer 2

• Anatomical barrier
• cellular component
• Humoral component

Question 3

What factors falls under anatomical barrier?

Answer 3

Mechanical, chemical + biological

Question 4

What cell is in the anatomical barrier?

Answer 4

epithelial cell

Question 5

What line of defense is the epithelial cell?

Answer 5

first line

Question 6

What does the epithelial cells have of content that makes it useful in the innate immune system?

Answer 6

Antimicrobial proteins:
Alpha + beta defensins
Histatins
Surfactant protein A + D

Question 7

What does epithelial cell secrete and why?

Answer 7

MUCUS –> prevent adhesion

Question 8

What disease/ condition does NOT have mucus?

Answer 8

cystic fibrosis

Question 9

What is the mechanical factors in the anatomical barrier?

Answer 9

Skin: keratinized, desquamatation + tight junction
Other: flushing action + mucus

Question 10

What are the chemical factors in the anatomical barrier?

Answer 10

Fatty acid, sweat, < pH, enzymes + surfactant (opsonins)

Question 11

What secretes low pH?

Answer 11

Skin + Stomach + Vaginal secretions (post-pubertal)

Question 12

What enzymes are found in chemical factors?

Answer 12

lysozymes + phospholipase

Question 13

What are biological factors?

Answer 13

Microbial antagonism + antimicrobial peptide

Question 14

How does the normal microbiota play a role in biological factors?

Answer 14

• prevent attachment
• compete for growth
• make bacteriocins
• maintain acid pH

Question 15

Which antimicrobial peptide play a role in biological factors?

Answer 15

Phospholipase + a & b defensin + ribonuclease

Question 16

What secretes antimicrobial peptide in biological factors?

Answer 16

skin, mucus membranes + intestinal Paneth cells

Question 17

What is the function of antimicrobial peptide in biological factors?

Answer 17

increased production induced in response to bacterial infection & pro-inflammatory cytokines

Question 18

which 2 oxygen methods do neutrophils kill in?

Answer 18

oxygen dependent + oxygen independent

Question 19

Explain oxygen dependent killing in neutrophils.

Answer 19

Phagocyte bind –> phagolysosome
way 1 –> H2O2 –> OH (RADICAL)
way 2 –> MPO + CL –> makes hypochlorite

Question 20

List enzymes in oxygen independent killing in neutrophils.

Answer 20

protease, phospholipase, nuclease, lysozymes, lactoferrin, glycosylase + basic protein + cationic (cathepsin)

Question 21

What are NK cells , do they require antigen and how do we find them (which CD)?

Answer 21

They are Large granular non-T, non-B lymphocytes
They dont require antigen
CD56+ CD16+ CD3

Question 22

What is the role of NK cell?

Answer 22

Important in immune response against virally infected cells & spontaneously arising tumors

Question 23

How does NK cell do its role?

Answer 23

Activate when T cell activate then apoptosis (by granules containing perforin + granzymes)

Question 24

How does NK cell work against virus?

Answer 24

Cell has MHC 1 --> virus bind and enter
Cell makes micA + micB --> NK bind with KAR + KIR
KAR *--> kill
KIR *--> doesnt kill
* one is usually more than the other

Question 25

What is cytokine?

Answer 25

small secreted proteins released by cells which may have anti or pro-inflammatory properties

Question 26

What ways can cytokine act?

Answer 26

paracrine or autocrine way

Question 27

What is a chemokine?

Answer 27

cytokine with chemotactic property

Question 28

Why is coagulation system activated?

Answer 28

- Tissue damage - Vasodilation - phagocyte chemotactic - antimicrobial activity

Question 29

What is complement system? And how many pathways are there and name and describe them.

Answer 29

Helps clear pathogen by aiding phagocytosis o Classical: has immune complex (antibody + antigen bound together) o Lectin pathway: manose binding lectin complex o Alternative pathway: pathogen coated by c3b

Question 30

Explain the classical pathway + its activation

Answer 30

Antigen + antibody --> C1 --> Antigen + antibody + C1 + C4B --> Antigen + antibody + C1 + C4B + C2A --> c3 covertase To activate: c3b + c5a

Question 31

Explain the lectin pathway + its activation

Answer 31

Antigen + MBL --> Antigen + MBL + C4B --> Antigen + MBL + C1 + C4B + C2A --> c3 covertase To activate: c3b + c5a

Question 32

Explain the alternative pathway + its activation

Answer 32

pathogen + C3B + FACTOR B --> (factor D makes factor Bb) -->pathogen + C3B + FACTOR Bb --> c3 covertase activation:c3 covertase + factor p + c3b --> c5 convertase + c5a + c3b

Question 33

What makes pores in MAC?

Answer 33

C9

Question 34

What is the c1 inhibitor?

Answer 34

serpin

Question 35

What is the c3 inhibitor?

Answer 35

DAF

Question 36

How to stop mac?

Answer 36

C59

Question 37

What complements activates basophil?

Answer 37

C3a + C4a + C5a

Question 38

What is opsonization?

Answer 38

Coating microbe with complement proteins

Question 39

What is the pathway to phagocytosis?

Answer 39

Opsonization and phagocytosis --> Inflammation --> Lysis

Question 40

How does the innate system recognize pathogens?

Answer 40

- PRR bind to PAMP - DAMP (tissue damage) - NK

Question 41

What are PAMP + PRR?

Answer 41

PAMP on bacteria --> needed for survival (e.g LPS + petidoglycan + DNA etc) PRR: toll like receptor that bind to PAMP --> initiate phagocytosis + cytokine + etc

Question 42

Are PRR in serum?

Answer 42

some can be! C-reactive protein (CRP) + serum amyloid

Question 43

How to activate complement?

Answer 43

1. Pathogen enter body 2. Chemotactic factors made by receptors (PRR) 3. PRR bind to PAMP on bacteria --> recognized by toll like receptor 4. Macrophage is activated --> phagocytosis 5. Cytokines (pro-inflammatory made) + chemokine 6. IL8 attract neutrophil 7. Neutrophils come --> transmigration --> inflammation

Question 44

What is an example of DAMP?

Answer 44

phosphatidylserine