Midterm 1

Question 1

Functional heterogeneity

Answer 1

Each cell type can express a subset of different receptor combinations

Question 2

Lectins

Answer 2

Scavenger receptor, binds carbohydrates, mannoes receptor

Question 3

Mannise receptor action

Answer 3

Surface sugar on bacterium bind to mangoes receptor extracellular domain. Macrophages invests bacteria via receptor mediated endocytosis, manise receptor travels with bacterium in endosome, but gets returned to surface before phagolysosome digests bacterium.

Question 4

What compliment receptor is on B cells and why

Answer 4

CR2, B cells must engulf antigen to present to helper t cell. CR2 binds iC3b and C3D.

Question 5

What is NF-KappaB

Answer 5

Proetein complex that controls DNA transcription and cytokine production.

Question 6

What do toll like receptors bind to

Answer 6

Every type of category of pathogen

Question 7

What is the goal of toll like receptors signaling?

Answer 7

Signaling immune cells to
1. Activate them to aquire features that increase their pathogen clearing capabilities
2. Induce secretion if cytokines that activate cytokines and adaptive immunity

Question 8

LRR

Answer 8

Leucine rich repeat region, pathogen recognition domain on TLRs

Question 9

Recognition factor for TLR4

Answer 9

Lipopolysaccharide, released from bacterial cell surface

Question 10

LBP

Answer 10

Lipopolysachharide binding protein binds LPS

Question 11

TLR4 to TLR4 complex pathway

Answer 11

1. Macrophage engulfed bacterium and releases LPS bound by LPB.
2. Endosome delivers LPS to CD14 exocytic vesicles
3. LPS is transferred to CD14 (coreceptor) on plasma membrane.
4. TLR4, LPS, and MD2 (coreceptor) forms a complex on plasma membrane

Question 12

TLR4 complex to kinase cascade

Answer 12

1.MyD88 (adaptor protein) binds to TIR domain of TLR4
2. IRAK4 binds to MyD88 and is activated
3. IRAK4 phosphorylation itself and dissociate from MyD88 then phosphosphorylates TRAF6 (adaptor protein)
4. TRAF6 initiates a kinase cascade

Question 14

Kinase cascade to activation of NF-kappaB

Answer 14

1. Kinase cascade activates IKK ( I kappa beta kinase) by phosphorylation
2. IKK phosphorylation inhibitory subunits of Ikappabeta/NF-kappaB complex
3. NF-kappaB transcription factor is free to be transcribed.

Question 15

IL-1Beta function

Answer 15

Causes secretion of inflammatory cytokines

Question 16

TNF-a

Answer 16

Induces more permeable blood cells

Question 17

IL-6

Answer 17

Induces fat and muscle to metabolize and generate heat

Question 18

CXCL8

Answer 18

Recruits neutrophils to infected tissue

Question 19

CCL2

Answer 19

Recruites monocytes to infected tissue

Question 20

IL-12

Answer 20

Recruits and activates natural killer cells

Question 21

Cytokine def’n

Answer 21

Small soluble molecule that can bind to something in the immune system. Short lived, act on short distances.

Question 23

Interferons

Answer 23

Cytokines released during a viral infection

Question 24

Why are type 1 interferon generated quickly

Answer 24

All human cells can generate type 1 interferons. Receptors are located on all nucleated cells all the time.

Question 25

Virus to IRF3 and IRF7 transcription factor.

Answer 25

1. Viral RNA binds to RIG1 2. RIG1 bound to RNA now binds to MAVS 3. Complex initiates signal via TRAF6 4. TRAF6 activates IRF3 and IRF7

Question 26

What response does IRF3 generate

Answer 26

IFN-BETA response. IFN-Beta binds type 1 IFN receptors on adjacent cells, practice response

Question 27

What response does IRF7 Induce

Answer 27

Autocorrect IFN-alpha response

Question 28

Plasmacytoid dendritic cells

Answer 28

Job is to produce IFNs. Use toll like receptors to detect infection.

Question 29

What to INF Alpha and Beta do

Answer 29

Induces synthesis of cellular proteins that will inhibitory viral replication in a cell.

Question 30

Caspase 1

Answer 30

Protease that cleaves inactive IL-1Beta into active form

Question 31

Macrophage adaptation for quick immune response

Answer 31

Activated IL-1beta is exits through a pore made by gasdermin D and the macrophage dies. Small portion of macrophages.

Question 32

What does IL-1Beta release trigger in other macrophages?

Answer 32

Synthesis and release of 5 cytokine categories.

Question 33

Overview of neutrophils recruitment, Rolling adhesion

Answer 33

Rolling adhesion: Recruitment of neutrophils from blood to tissue is mediated by complimentary pairs of adhesion molecules.

Question 34

Selectins

Answer 34

Adhesion molecules on neutrophils and endothelial cells that bind glyvoproteins

Question 35

S-Le*

Answer 35

Small Lewis carbohydrates. Get bound by selectins to slow neutrophils as they flow through blood

Question 36

Rolling adhesion to tight binding (neutraphils)

Answer 36

Many weak interactions with iCAM-1 (endothelial cells) and LFA-1 on neutrophils

Question 37

Rolling adhesion

Question 38

CXCL8 role in neutrophils transport

Answer 38

CXCL8 binds to gpcr, g protein activates and and disociates into 2 subunits and chemicals takes neutrophils to the site of infection.

Question 39

What do neutrophils do

Answer 39

They have toxic granules that destroy bacteria once engophed after being recognized by a receptor. Short lived.

Question 40

NETosis

Answer 40

Nucleus of neutrophils swells then bursts and extrudes chromatin to capture microbes

Question 42

Pyrogen

Answer 42

Cytokines and other molecules that produce fever which negatively impacts most pathogens

Question 43

Synthesis of Acute phase proteins

Answer 43

Released in response to bacteria inducing macrophages to produce IL6 which acts on hepatocytes to induce synthesis of acute phase proteins

Question 44

CRP

Answer 44

Pentraxin that binds a variety if pathogens and acts as an sopsonjn triggering the classical pathway of compliment. High in acute infection

Question 45

Serum amyloid A protein

Answer 45

Stimulates production of cytokines by binding to cell surface receptors on macrophages.

Question 46

MBL

Answer 46

Mannose binding lectin. Acute phase proteins that binds to mangoes on pathogens, not om human cells.virvulates serum with HDL.

Question 47

MASP1 AND MASP2

Answer 47

MBL associates serine protease that cleave compliment. MBL binds to pathogen then cleavage occurs.

Question 48

MBL lectin pathway of compliment activation

Answer 48

MASP2 cleaves C4 into C4a and C4b, C4b attaches ro microbe. MASP2 then leaves C2 into C2a and b and c2b attaches to C4b and forms C4bC2a

Question 49

C4bC2a

Answer 49

C3 convertase. Binds C3 and cleaves into C3a and b C3b attaches to surface.

Question 50

Classical pathway of compliment activation overview

Answer 50

CRP can activate as well as igG and igM. CRP bound to phosphorylcholine (pathogen) binds C1. C1 acts like MBL to create C3 convertases.

Question 52

C1 classical pathway

Answer 52

C4b binds to pathogen surface, C1 cleaves C2 into a and b subunits and C2a binds to C4b forming C4bC2a (C3 convertase)

Question 53

Natural killer cells

Answer 53

Need to know target is for sure foreign. Discharge toxic granules.

Question 54

Type 1 interferons and NK cells

Answer 54

INF BETA AND ALPHA reach NK cell. Induce apoptosis.

Question 55

IL12 and Nk cells.

Answer 55

Recruits eachother. Macrophages release cytokines that revruit NK cells. Macrophage and NK cells conjugate and macrophage delivers IL12. NK cells is now activated and proliferate into effector NK cells.

Question 56

Effector NK cells

Answer 56

Secrete IFN-Y which binds to receptor in macrophage and increases phagocytosis and cytokine secretion.

Question 57

Dendritic cells and NK cells

Answer 57

When NK cells are abundant, they outbumber dendritic cells and kill them. When they are scarce dendritic cells mature and initiate the adaptive immune response.