Cytokines

Question 1

What is a Cytokine

Answer 1

Communicating proteins
Bind to autocrine,paracrine and endocrine cells
Regulate immune responses
Alter gene expression
Can be pleiotropic

Question 2

Which molecules are cytokines

Answer 2

IL
Monokines
Lymphokines
Chemokines

Question 3

Chemical structure of cytokines

Answer 3

Low molecular weight proteins
High affinity for receptors
Active in picomole amounts

Question 4

What is the action of cytokines

Answer 4

Autocrine
Paracrine
Endocrine

Question 5

Pleiotropy

Answer 5

Affects multiple cell types
Ex: IL-4 effects B cells, Thymocyte and mast cells for proliferation

Question 6

Redundancy

Answer 6

Multiple cytokines affects cells of the same type
Ex: IL-2,IL-4,IL-5 all effect B cell for proliferation

Question 7

Synergestic

Answer 7

Cytokines acting in concert on the same cell
Ex: IL-4 + IL-5 effect B cell to induce class switch to IgE

Question 8

Antagonistic

Answer 8

Competing cytokines
IL-4 effects B cell to class switch to IgE
IFN-y effects B cell to block the effects of IL-4

Question 9

Cascade induction of Activated T helper cells

Answer 9

Activated helper T cell— IFN-y— Macrophage— IL-12 — activated T helper cells— IFN-y, TNF ,IL-2 and other cytokines

Question 10

Where do cytokines coming from

Answer 10

Macrophage
Granulocyte
Fibroblast
Endo cells
Mast cells
Lymphocytes
Produced also by non immune cells= fibroblasts,endo cells

Question 11

Cytokine interactions

Answer 11

Direct contact
Release of soluble mediators

Question 12

Innate immunity cells

Answer 12

Monocytes
DC cells
Macrophages
Neutrophils
NK cells
Megakaryocytes
Granulocytes
All of them do differentiation

Question 13

Adaptive immunity cells

Answer 13

TC cells
Tree cells
TH1 cells
TH2 cells
B cells
Plasma cells

Question 14

Role of cytokines in innate immunity

Answer 14

Inducing inflammation
Inhibiting viral replication
Promoting T cell responses
Limiting innate immune responses

Question 15

Main cell source of TNF

Answer 15

Macrophages
T cells

Question 16

Cellular targets and biological effects of TNF

Answer 16

Endo cells= inflammation, coagulation
Neutrophils = Activation
Hypothalamus = Fever, muscle and fat catabolism
Many cell types= apoptosis

Question 17

Main source of IL-6

Answer 17

Macrophages
Endo cells
T cells

Question 18

Cellular targets and biological effects of IL-6

Answer 18

Liver= synthesis of acute-phase proteins
B cells= proliferation of ab-producing cells
T cells= T helper 17 differentiation

Question 19

Cellular targets and biological effects of IL-15

Answer 19

NK cells= proliferation
T cells= proliferation of memory CD8 cells

Question 20

TNF mainly produced by

Answer 20

Macrophages
DCs

Question 21

TNF is mediator of

Answer 21

Acute inflammatory response to bacteria and other infectious microbes

Question 22

IL-1 şs the mediator of

Answer 22

Acute inflammatory response

Question 23

Major cellular source of IL-1

Answer 23

Activated mononuclear phagocytes — Macrophages, Neutrophils, Epi cells, Endo cells

Question 24

IL-6 is an important cytokine in

Answer 24

*Acute inflammatory responses
Induces the synthesis of acute phase reactants by liver
Stimulates neutrophil production in BM
Promotes differentiation of IL-17 producing helper cells
** Rheumatoid arthritis

Question 25

Cytokines that have a multiple local and systemic inflammatory effects

Answer 25

TNF
IL-1
IL-6

Question 26

*Functions of IL-2

Answer 26

Stimulates the survival, proliferation and differentiation of ag-activated T cells
Required for the survival and function of regulatory T cells

Question 27

Effector T cells
Defining cytokines
Principal target cells
Are used for Helminths?

Answer 27

Effector T cell= TH2
Cytokine= IL-4,IL-5,IL-13
Target cells= Eosinophils