1. Cytokines and Chemokines Chapter 6

2. What are cytokines?
Cytokines are low-molecular weight regulatory proteins or glycoproteins secreted by white blood cells and various other cells in the body in response to a number of stimuli
Mediate the interactions and communication between immune cells
Regulating the development of immune effector cells.
They bind to specific receptors on target cells to elicit a specific biological response

4. Action of Cytokines Autocrine Affects the generating cell (self)
Paracrine
Affects on neighboring
Endocrine
Affects cells remote from the secreting cell

6. Action of Cytokines Pleiotropy Redundancy Synergy Antagonism Cascading
Affects multiple cell types
Redundancy
Multiple cytokines affects cells of the same type
Synergy
Cytokines acting in concert on the same cell
Antagonism
Competing actions
Cascading
Cytokines acting sequentially

8. Cytokine Receptors Ig super family Class I- hematopoietic
Class II-interferon
TNF
Chemokine

13. Role of Cytokines in Hematopoiesis
SCF (Stem cell factor)
GM-CSF (Granulocyte-macrophage colony- stimulating factor)
IL-3 (Interleukin 3)
IL-5 (Interleukin 5)
IL-7 (Interleukin 7)
IL-11(Interleukin 11)

15. Cytokines in the Immune Response
Innate immune response
IL 1-(Macrophage)-fever, capillary effects
IL 6-(Macrophage)-adaptive immunity via B cells
IL 12(Macrophage)-adaptive immunity via T helper cells
TNF (Macrophage)-capillary effects, activates neutrophils
IFN alpha (Macrophage)-multiple effects
IFN beta (Fibroblasts)-multiple effects

16. Cytokines in the Immune Response
Adaptive immune response
IL 2-(T cells)-multiple effects)
IL 4-(T cells & mast cells)-T cell differentiation, IgE production
TGF beta –(T cells, macrophages)-inhibits adaptive immune response
IFN gamma-(T cells, NK cells)-Macrophage activation

18. Top half of Fig. 2-47

19. Cytokines of T helper Cells

21. Chemokines
Chemokines are a family of chemoattractant cytokines (small proteins secreted by cells that influence the immune system) which play a vital role in cell migration
classified as chemokines according to behavior and structural characteristics.
all approximately 8-10 kilodaltons in mass and have four cysteine residues in conserved locations that are key to forming their 3- dimensional shape.
Chemokines have been classified into four main subfamilies: CXC, CC, CX3C and XC.
All of these proteins exert their biological effects by interacting with transmembrane receptors called chemokine receptors

22. Some chemokines and their functions