Lecture 12+13

Question 1

Cytokines

Answer 1

Signaling molecules of the immune system

Question 2

Cytokines Function

Answer 2

1. Cell Adhesion
2. Cell Motility
3. Enzymatic Activities
   Metabolic Enzymes
4. Transcriptional Regulation
5. Cell Proliferation
6. Cell Survival/ Apoptosis

Question 3

Chemokines

Answer 3

Cytokines that induce cell migration
Chemoattractants

Question 4

Endocrine Action

Answer 4

Endocrine action –> Circulation –> Distant Cell

Question 5

Endocrine Examples

Answer 5

1. Erythropoietin
2. GM-CSF
3. G-CSF
4. M-CSF
5. Thrombopoietin
   CSF- Colony stimulation factors

Question 6

Paracrine Action

Answer 6

Paracrine action –> Nearby Cell

Question 7

Paracrine Examples

Answer 7

1. Interferon signaling by virally-infected cells
2. Leukocyte development in bone marrow niches
3. DC direction of TH cell differentiation
   DC: Dendritic Cells

Question 8

Autocrine Action

Answer 8

Autocrine cell –> Self-signaling

Question 9

Autocrine Action

Answer 9

IL-2 self-signaling by Tc cells following activation by DCs

Question 10

Primary Producers of Cytokines

Answer 10

1. Macrophage
2. Dendritic Cells
3. TH Cells

Question 11

Macrophage (Sentinel Cell)

Answer 11

Released cytokines communicate with
1. Vascular
2. Cooperating immune cells
(Neutrophils)
3. Hematopoietic Stem Cells

Question 12

Macrophage Benefits

Answer 12

1. Increase blood flow (leukocytes)
2. Increase Vascular Permability
3. Increase WBC attraction

Question 13

Dendritic Cells

Answer 13

Antigen presentation to and differentiation of T cells

Question 14

Dendritic Cells Purpose

Answer 14

1. Ability to assess the pathogen
2. Persuades TH cells best fit to fight pathogen

Question 15

XP Proliferation Receptors

Answer 15

IL-2R

Question 16

XP Differentiation Receptors

Answer 16

1. IL-4R
2. IL-12R
3. IL-17R

Question 17

TH1

Answer 17

Cell Mediated

Question 18

TH2

Answer 18

Humoral

Question 19

TH17

Answer 19

Inflammatory

Question 20

TH Cells

Answer 20

Coordinates immune responses

Question 21

TH1 Cells

Answer 21

1. Induced by IL-12 and IFN-g
2. Activates macrophage and TC cells
   APC licensing
3. Promotes the cell-mediated immune response

Question 22

TH2 Cells

Answer 22

1. Induced by IL-4 and IL-5
2. Activates B-Cells
3. Promotes the Humoral Immune Response

Question 23

TH17 Cells

Answer 23

1. Induced by IL-17 and IL-23
2. Activates macrophage and neutrophils
3. Supports the inflammatory state/ innate response

Question 24

Secondary Producers of Cytokine Signaling

Answer 24

1. Lymphocytes
2. Myeloid
3. Granulocytes
4. Monocytes

Question 25

Secondary Producers of Cytokine Signaling (2)

Answer 25

1. Epithelial Cells 2. Endothelial Cells 3. Neurons 4. Muscle Cells 5. Connective Tissue Cells

Question 26

Six Families of Cytokines and Associated Receptors

Answer 26

1. Interleukin-1 Family 2. Hematopoietin Family (Class I Cytokine) 3. Interferon Family (Class II Cytokine) 4. Tumor Necrosis Factor Family 5. Interleukin-17 Family 6. Chemokines

Question 27

Interleukin-1 (IL-1) Family

Answer 27

1. Secreted by dendritic cells, monocytes, and macrophage 2. Secreted early in the innate response 3. Generally pro-inflammatory

Question 28

IL-1 Major Players

Answer 28

IL-1, IL-6, TNFa (alpha)

Question 29

IL-1 Receptors

Answer 29

1. Immunoglobulin Superfamily 2. Heterodimer of IL-1R1, IL-1RAcP 3. IL-1RI - functional arm of the heterodimer - activated by either IL-1a or IL-1b 4. IL-1RAcP - NO signaling activity on its own - promotes Il-1RI binding/signaling

Question 30

IL-1: Pro-inflammatory Response

Answer 30

1. Vascular Endothelial Cells - increased vascular permeability - increased neutrophil adhesion 2. Vascular Smooth Muscle Cells - increased local blood flow

Question 31

IL-1 Receptor Inhibitor (Turns Off)

Answer 31

1. Inhibitory Ligands 2. Inhibitory ('Decoy') Receptors

Question 32

Inhibitory Ligands

Answer 32

IL-1Ra: ligand competition

Question 33

Inhibitory ('Decoy') Receptors

Answer 33

1. IL-1RII: binding but NO transduction 2. sIL-1RII: buffers IL-1 abundance 3. sIL-1RAcP: buffers IL-1 abundance

Question 34

Hematopoietin Family

Answer 34

1. Many contribute to regulating hematopoiesis 2. Others moderate key B-Cell and T-Cell development steps

Question 35

Hematopoietin Family

Answer 35

Class I is a historical reference to the discovery of its earliest members

Question 36

Cytokine Structure

Answer 36

Four-helix bundle motif

Question 37

Four Anti-Parallel a- helices

Answer 37

1. IL-2, -3, -4: Short helices (8-10 amino acids) 2. IL-6,-12: Long helices (10-20 amino acids)