Lecture 4

Question 1

What is innate immunity?

Answer 1

the initial host defense response to pathogens that prevents, controls, or eliminates infection

Question 2

Neutrophil function

Answer 2

early phagocytosis and killing of microbes

Question 3

macrophage function

Answer 3

efficient phagocytosis and killing of microbes, secretion of cytokines that stimulate inflammation

Question 4

NK cells function

Answer 4

lysis of infected cells, activation of macrophages

Question 5

Function of complement

Answer 5

killing of microbes, opsonization of microbes, activation of leukocytes

Question 6

mannose-binding lectin (collectin) function

Answer 6

opsonization of microbes, activation of complement (lectin pathway)

Question 7

C-reactive protein (pentraxin) function

Answer 7

opsonization of microbes, activation of complement

Question 8

THF, IL-1, chemokines function

Answer 8

inflammation

Question 9

IFN-a, B function

Answer 9

resistance to viral infection

Question 10

IFN-y function

Answer 10

macrophage activation

Question 11

IL-12 function

Answer 11

IFN-y production by NK cells and T cells

Question 12

IL-15 function

Answer 12

proliferation of NK cells

Question 13

IL-10, TGF-B function

Answer 13

control of inflammation

Question 14

what is a PAMP?

Answer 14

pathogen-associated molecular pattern

Question 15

Cell receptors that recognize PAMPs are called what?

Answer 15

pattern recognition receptors (PRRs)

Question 16

Why do phagocytes use PRRs?

Answer 16

to distinguish self from non self

Question 17

What do toll like receptors (TLRs) do?

Answer 17

recognize pathogens and activate inflammation

Question 18

where are TLRs expressed?

Answer 18

on immune cells, including monocytes, neutrophils, macrophages, and dendritic cells

Question 19

What are nucleotide oligomerization domain (NOD) like receptors (NLRs)

Answer 19

a specialized group of intracellular proteins that play a critical role in the regulation of the los innate immune response

Question 20

What is the function of NLRs?

Answer 20

act as a scaffolding protein that assemble signaling platforms that trigger NF-KB and mitogen activated protein kinase (MAPK) signaling pathways

Question 21

NLRs contort the activation of inflammatory _____

Answer 21

caspases

Question 22

What is necrosis?

Answer 22

passive, catabolic cell death in response to external toxic factors

Question 23

Inflammation is an innate reaction caused by what?

Answer 23

1. increased blood supply to area–redness and heat
2. increased capillary permeability– leak from blood vessels–swelling and pain
3. massive influx of neutrophils
4. arrival of monocytes/macrophages
5. distortion of the homeostasis and loss of function

Question 24

What are defensins?

Answer 24

small cationic peptides that contain both cationic and hydrophobic regions

Question 25

What produces defensins?

Answer 25

epithelial cells of mucosal surfaces and granule containing leukocytes including neutrophils, NK cells and CTLs

Question 26

What are cathelicidins?

Answer 26

direct toxicity to microorganisms and the activation of leukocytes

Question 27

What are the functions of NK (natural killer) cells?

Answer 27

• recognize ligands on infected cells or cells undergoing other types of stress
• kill those infected or stressed cells
• eliminate reservoirs of infection and thus release intracellular pathogens for phagocytosis