lect 11.2

Question 1

what do DC recognizing PAMPs lead to

Answer 1

activation of phagocytosis

DC migrate of lumph noes carrying intact or degraded pathogens and bind them to MHC to be recognized by T cells so they can be activated

Question 2

phagocytosis

Answer 2

engulfment and internalization of materials such as microbes for their clearance and destruction

Question 3

what are the steps for phagoxytosis

Answer 3

1. bact binds on PRRs on membrane invaginatinoss called pseudopodia
2. bact ingester and forms a phagosome
3. phagosome fuses with lysosome
4. bact is killled and digested by low PH actiavted lysossomal enzymes
5. digestion products released from ecll

Question 4

what cells do phagocytosis

Answer 4

macrophages
neutrophils
immature dendritic cells

Question 5

macrophages examples

Answer 5

kuppfer cells- liver
microglial cells- CNS
alveolar macrophages- lung
perioneal macrophages- peritoneal fluid

Question 6

what are langerhan celsl

Answer 6

immature dc capable of doing phagocytosis in the skin and mucosa

Question 7

how are microbes recognized

Answer 7

directly via the PRR: PAMP interaction

phagocytes recognize soluble proteins bound to microbes thorugh opsonin receptors in a process called opsonization

Question 8

what are the types of soluble factors

Answer 8

interferons

cytokines

complement

Question 9

what are interferons

Answer 9

protiens (cytokines) produced by virus infected cells that induce antiviral response in neighbouring

Question 10

what produces interferons cytokines

Answer 10

virus infected cells

Question 11

what do interferons induce

Answer 11

antiviral response in neighbouring cells

Question 12

what are cytokine exampes

Answer 12

ILs 1 + 6, TNF a

Question 13

what do cytokines do

Answer 13

induce and support inflamatory responses

Question 14

what is complement

Answer 14

a group of proteins that are produced in the liver and are found in the blood and lymph

Question 15

what does complement do

Answer 15

recognizes PAMPs and kils pathogens by lysis or opsonization

Question 16

where are complenet protiens synth

Answer 16

in the liver

Question 17

what is the IFN system

Answer 17

phase 1 and 2

phase 1 detectino leads to production of IFN a/B promoter

phase 2- activation of IFN regulated anti viral genes

Question 18

what causes induced cellular innate responses

Answer 18

type I interferons which have potent antiviral effects

Question 19

how are dead/ dying cells cleared

Answer 19

macrophages clear apoptotic or necrotic cells via recognition of DAMPs

Question 20

what inhibits phagocytosis by macrophages

Answer 20

cd47- healthy cells express this

Question 21

what are DAMPs

Answer 21

eat me signals - PS, LPC

Question 22

what does tissue damage and bacteria cause

Answer 22

resident sentinel cells to release chemoatttractants and vasocative factors to inc blood flow and permeablity

this lead to influx of fluid and cells

neutrophils and macrohpages migrate to site of infection due to chemotaxis

phacocytes and antibacterial substanes destroy bacteria

Question 23

characteristics of inlamation

Answer 23

Characteristics of
Inflammation
* Heat
* Redness
* Swelling
* Pain
* Loss of function`

Question 24

what acts as a bridge between innate and adaptive systems

Answer 24

dendritic cells

bring Ag from site of infection for T cell presentation and activation in lymph nodes so they can differentiate into pathogen specfiic subsets for Ag clearance