Lecture 2: Innate part 1

Question 1

host defence peptides are secreted by ____ in response to ____. how do they work?

Answer 1

epithelial cells

pathogens

the proteins are cationic and the membrane is anionic, so they bind to each other, create a pore causing cell lysis and the bacteria dies

Question 2

innate immune cells look for two things: PAMPS and DAMPS. What are they?

Answer 2

PAMPS: pattern asscociated molecular patterns

PAMPs are things on the outside of bacteria that the cell recognizes, like a molecular motif, like flagella of bacteria.

DAMPS: danger associated molecular patterns

DAMps things found on our own cells that the immune system needs to attack such as cancer cells or aged dying cells

Question 3

how do our immune cells recognize PAMPS and DAMPs?

Answer 3

thru pattern recognition receptors (PRR). they bind to the PAMPs or DAMPs, and this recruits other cells to come and get rid of the culprit

Question 4

where are PRRs found?

Answer 4

extracellular, cell surface, and intracellular

all for detection of different levels of infections

Question 5

what are TLRs?

Answer 5

toll-like receptors, a type of cell surface PRR (pattern recognition receptor)

Question 6

TLRs recnognize _____ but are also able to identify ____.

Answer 6

PAMPs, DAMPs

Question 7

TLRs are proteins with 3 parts, which are:

Answer 7

an N terminal with leucine rich repeats where PAMPs and DAMPs bind

a single transmembrane helix of mostly hydrophobic residues

a c terminal which is inside the cell

the leucine rich repeats are dimers and bind to each other

Question 8

TLR7 and TLR8 bind to what ligand?

Answer 8

single-stranded RNA, so it identifies viruses

Question 9

TLR4 identifies what class of bacteria?

Answer 9

gram negative

Question 10

TLR2 and TLR4 identify ____

Answer 10

fungi

Question 11

cells such as ____ and ____ have a lot of TLRs to detect PAMPs

Answer 11

macrophages

dendritic cells

Question 12

what is LPS? which TLR recognizes it?

Answer 12

lipopolysaccharide (prototypical endotoxin), the main outer membrane of gram-negative bacteria

TLR 4

Question 13

why are TLR7 and TL8 inside the cell?

Answer 13

because they identify viruses, so they need to be inside the cell!

Question 14

PRR signaling activates a large number of _____ such as ____

Answer 14

genes

MyD88 gene that makes a protein involved with signaling within immune cells

Question 15

most TLR pathways are ____ dependent, and most also activate the _____which is _____

Answer 15

MyD88

franscription factor NF-kB

involved in immune and inflammatory responses

Question 16

NF-kB transcription factors are pro_____ and ______

Answer 16

inflammatory cytokines

chemokines

Question 17

type 1 interferons demonstrate____

Answer 17

potent antiviral activity

Question 18

what are C type lectin receptors? CLR? what do they do? where are they found?

Answer 18

they are surface PRRs and phagocytic receptors. they recognize cell wall component sugars/polysaccharides of bacteria/fungus/yeast

mostly in cells that phagocytize like macrophages and dendritic cells

Question 19

CLRs trigger a variety of _____ pathways similar to those acitbaed by TLRs and promote _____

Answer 19

inflammatory

phagocytosis

Question 20

mannose receptor CD206 recognizes _______ and triggers _____ of bound microbes

Answer 20

terminal mannose, fucose, and N-acetyl glucosamine resiudes (all commonly found in microbes)

phagocytosis

Question 21

what is an inflammasome?

Answer 21

https://www.youtube.com/watch?v=2812ion3aUk

Question 22

what do NOD receptors do?

Answer 22

found in the cytosol of the cell, detect intracellular dangers like infection or cellular damage through an inflammasome to induce cell death and inflammation