Signalling.ppt
- 1. Lecturer: Ge Jin, Ph.D., ge.jin@case.edu, 3683791 Learning Objectives: 1. describe basic properties of cytokines 2. describe how cytokines regulate immunity (e.g. increase or decrease MHC expression and T cell activation…) 3. cytokine and oral diseases NOTE: you need to download the PowerPoint file to your computer to read notes. Slides containing research results from my lab will be added during the lecture.
- 2. Cytokines properties, categories, signaling, function Body as Host: Immune Molecules
- 3. Cytokines small, secreted, non-antibody proteins produced by cells involved in both innate & adaptive immunity mediate and regulate immunity, inflammation, and hematopoiesis
- 4. Cytokines Lymphokine: made by activated lymphocytes, especially TH cells, e.g. IL-2 Monokine: made by mononuclear phagocytes, e.g. Mig/CXCL9 Chemokine: chemotactic activity, e.g. IL-8, CXCL12 Interleukin: interaction between leukocytes IL-1, IL-8, IL-10, IL-13…… named by activity: Tumor Necrosis Factor a (TNFa), Colony Stimulation Factor (CSF), Transforming Growth Factor b (TGFb)….
- 5. Cytokines grouped by structures into families interferons (IFN): type I (IFNa and IFNb), type II (IFNg) Interleukin: IL-1, IL-2 chemokine: CXCL and CCL chemokines TNFa: TNFa, FasL, CD40L… hematopoietin: erythropoietin (EPO), colony- stimulation factors (CSF)
- 6. Properties of Cytokines produced in response to immune stimuli -- not store pre-formed -- synthesis: DNA mRNA protein secretion -- slow cellular response can act on the cells that produce them (autocrine action) can act on nearby cells (paracrine action) can act on distance cells (endocrine action)
- 7. Properties of Cytokines can be produced by many cell types and act on many cell types (pleiotropic) different cytokines can have similar actions (redundant)
- 8. -- share receptors -- defect in a unique cytokine have little effect -- defect in a share component (common receptor) can have profound effects e.g. IL-2Rg defect X- linked SCID (Severe Combined Immunodeficiency)
- 9. Properties of Cytokines can modulate synthesis of other cytokines - cascades: e.g. TNFa IL-1 IL-6, IL-8… - enhance or suppress production of other cytokines: positive or negative influence the action of other cytokines - antagonistic - additive - synergistic short half life, low plasma concentration, bind to receptor with high affinity
- 10. Immunoglobulin superfamily: IL1R, TLRs… Cytokine Receptors (grouped by structures into families) Toll-IL-1 Receptor domain (TIR) Toll-like receptors (TLRs) leucine-rich repeats immunoglobulin domain IL-1 receptor cell membrane
- 11. TNFR family: TNFa, FasL, CD40L… Cytokine Receptors
- 12. Cytokine Receptors GM-CSFRa IL-3R IL-5R b b b GM-CSF IL-2 IL-3 IL-5 IL-15 IL-7 IL-9 g g g g IL-2Ra IL-2b IL-15Ra IL-2b IL-7R IL-9R class I receptor family: hematopoietin family gp130 gp130 gp130 gp130 CNTFR cell membrane cell membrane GM-CSF: Granulocyte macrophage colony-stimulating factor IL: interleukin gp130: glycoprotein 130 (m.w. 130 kDa) IL-6 IL-11 CNTF LIF/OSM
- 13. class II receptor family: Interferon a, b, and g Cytokine Receptors IFNARI IFNAR2c IFNAR2b IFNgRa IFNgRb type I IFN receptor type II IFN receptor cell membrane type I IFN: IFNa and IFNb, type II: IFNg
- 14. chemokine receptor family: CCR1-5, CXCR1-4 NH3 binding of a ligand to the receptor Cytokine Receptors cell membrane
- 15. Cytokine Receptors TGFb receptors TGFb receptors have intrinsic kinase activity when interacting with ligands.
- 16. Cytokine Signaling cytokines membrane receptors phosphorylation cascades transcription, Ca++… signal transduction binding activation
- 17. Cytokine Signaling NFkB signaling pathways JAK/STAT signaling pathways Chemokine signaling pathways Cross-talk between pathways
- 18. NFkB Signaling NFkB signaling inducers: cytokines: IL-1, TNFa,… microbial cell components: Fn cell wall, lipopolysacchrides (LPS),… virus: retroviruses, double-stranded RNA (dsRNA),… Receptors: IL-1 receptors Toll-like receptors (TLRs, innate immunity) TNFa receptors Nuclear Factor k B (NFkB): dimeric transcription factors: p65/RelA, c-Rel, RelB, p105/p50, p100/p52 sequestered by inhibitory IkB proteins and retained in cytosol in resting cells
- 19. NFkB IRAK TRAF6 p p pellino1 IkB IkB p p TF IRAK p p p p u u degradation u TAK1 u u u u p p IkB IkB ubiquitination& degradation u u TRAF6 p TAK1 TAB1 TAB3 TAB2 Ubc13/Uev1A complex III IRAK TRAF6 p p IRAK4 pellino1 TAK1 TAB1 TAB3 TAB2 p complex II IKKa IKKb p p u ubiquitination phosphorylation IL-1 receptor IRAK Tollip MyD88 IRAK4 TRAF6 p p complex I IL-1 nucleus IL-6 IL-8 hBD-2 …. innate & adaptive immunity p NFkB p p TF NFkB p
- 20. NFkB Signaling Alternative NFkB activation pathways of immunity CD40L, LT-B, BAFF NIK IkB degradation NFkB activation CD4/TCR PKC UV-light p38-CKII
- 21. JAK/STAT Signaling Pathway JAK (Janus Kinases): a family of tyrosine kinases, JAK1-3, Tyk2 STAT (Signal Transducers and Activators of Transcription): transcription factors, STAT1-6,… Cytokines: IFNa/b, IFN-g, Epo, GM-CSF, IL-6, IL-13… in resting cells, non-phosphorylated, monomeric STATs reside in cytosol
- 22. SJ Baker et al, Oncogene (2007) 26, 6724–6737.
- 23. IFNa/b IFNg receptor Receptor JAKs Receptor JAKs STATs DNA STAT dimers target gene transcription nucleus cdc25a, cyclin D1~3, c-myc, cyclin E, MMP9 p21, caspase 3, 1, 8…
- 24. Chemokine Signaling 2 major families: the CCL family and CXCL family CCL1~27, CXCL1~14 receptors: G-protein coupled 7 transmembrane
- 25. a b g Gai b a g PI-3K MAPK PLC target genes Adhesion, polarization, chemotaxis CCL12 (SDF) signaling p p GRK b-arrestin recycling degradation
- 26. Cross-talk between Cytokine Signaling Pathways chemokine receptor interferon receptor IL, TLR, TNFa receptors STATs NFkB PI-3K TAK1 TGFb receptor
- 27. Cytokines and Immunoregulation Mediators of Innate Immunity Mediators of adaptive immunity Stimulators of hematpoiesis
- 28. Cytokines and Immunoregulation Mediators of Innate Immunity TNFa IL-1 IL-10 IL-12 IFNa, IFNb IFNg Chemokines Mediators of adaptive immunity Stimulators of hematpoiesis
- 29. Tumor Necrosis Factor a (TNFa) Produced by activated macrophages and T cells Most important mediator of acute inflammation in response to microbes, such as LPS Induces production of myeloid CSFs, IFN-g, IL-6, IL-8 and other chemokines Mediate recruitment of neutrophils and microphages to site of inflammation by stimulating cells to produce adhesion molecules (e.g. ICAM-1) Stimulates endothelial cells and macrophages to produce chemokines A potent pyrogen causing fever by direct action or via IL-1 Promotes production of acute phase proteins, such as CRP Roles in rheumatoid arthritis, psoriasis, tuberculosis, …
- 31. Interleukin 1 (IL-1) Produced by activated macrophages, stimulated lymphocytes, keratinocytes, fibroblasts Activates the NFkB signaling pathway (similar effects to TNF) Helps activate T cells Can be induced by inflammation, injury, and infection
- 32. Interleukin 10 (IL-10) Produced by macrophages, B cells, Th2 cells Originally identified as cytokine synthesis inhibitory factor Suppresses inflammatory responses Inhibits production of IFN-g, IL-2, IL-3, TNFa, GM-CSF Stimulate thymocytes, mast cells, B cells Limits Th1 response, promotes Th2 cell development, shifts response to Th2 type (phagocytosisAb production) Inhibits expression of class II MHC and co-stimulatory molecules on macrophages
- 33. Interleukin 12 (IL-12) Produced by macrophages, dendritic cells, Tc cells, NK cells Belongs to the IL-6 cytokine family Has immunoregulatory effect on NK cells and T cells Stimulates production of IFN-g Promotes Th cells Th1 Enhances differentiation of Cytotoxic T Lymphocytes (with IL-2) Enhances cytolytic functions of T cells and NK cells
- 34. Type I Interferon (IFN-a, IFN-b) Produced by macrophages and virus-infected cells Inhibits viral replication in cells via PKR and RNaseL Increases expression of MHC I and Tc mobilization Stimulates production of IFN-g by activated T cells Activate NK cells
- 35. Type II Interferon (IFN-g) Produced primarily by Th1 Induce ICAM production in endothelial cells Activate NK cells Increase MHC I and MHC II expression to help Th cell and APC interaction Promotes B cell differentiation to plasma cell Promotes cytotoxic T cell differentiation
- 36. Chemokines Produced by many leukocytes and other types of cells Large family of molecules (over 50) Have significant structural homology and overlapping functions Chemotactic for leukocytes, such as PMN, T and B cells Recruit leukocytes to sites of infection and inflammation Involved in lymphocytes trafficking, wound healing, metastasis, angiogenesis, lymphoid organ development….
- 37. Cytokine in Immunregulation Mediators of Innate Immunity Mediators of adaptive immunity IL-2 IL-4 IL-5 TGFb IL-10 IL-12 IFN-g Stimulators of hemotopoesis
- 38. Interleukin 2 (IL-2) Produced by lectin- or antigen-activated Th cells Powerfully immunoregulatory lymphokine Main growth factor for both T and B lymphocytes Activates NK cells and monocytes CTLA-4: Cytotoxic T-Lymphocyte Antigen 4, inhibits T cell function.
- 39. Interleukin 4 (IL-4) Produced by macrophages, Th2 cells, activated B cells Has complex biological actions via cytokine production Enhances antigen-presenting activity of B to T cells Stimulates development of Th2 cells from naïve Th cell Stimulates Ig class switch from IgG1 to IgE (allergy)
- 40. Interleukin 5 (IL-5) Produced by Th2 cells Originally identified as a B cell differentiation factor Aids in the growth and differentiation of eosinophils and late-developing B cells to plasma cells
- 41. Transforming growth factor b (TGFb) Produced by T cells, macrophages, other cell types 30 members Have effect on many cell types Have pro- and anti-inflammatory effect Inhibits proliferation of T cells and activation of B cells Acts on PMNs and endothelial cells to block the effects of pro-inflammatory cytokines
- 42. Cytokine and Immunoregulation Mediators of Innate Immunity Mediators of adaptive immunity Stimulators of hematopoiesis (Colony Stimulating Factors) GM-CSF: promotes differentiation of bone marrow progenitors M-CSF: promotes growth and differentiation of monocytes and macrophages G-CSF: promotes production of PMNs
- 44. Regulation of Immune Responses regulatory mechanisms: recognition phase
- 45. Regulation of Immune Responses regulatory mechanisms: antibody antibody competes with B cells for antigen antigen/antibody complexes binding to Fc receptors sends an inhibitory signal to B cells
- 46. Regulation of Immune Responses regulatory mechanisms: Tregs Regulatory T cells (Tregs) do not inhibit initial T cell activation and proliferation They are not Th1 or Th2 cells They can suppress both Th1 and Th2 responses They inhibit a sustained response and prevent chronic and potentially damaging responses
- 47. Regulation of Immune Responses regulatory mechanisms: Tregs Naturally occurring Tregs CD4+CD25+Foxp3+ cells derived from thymus IL-2, cell contact dependent inhibition Foxp3 is required for Treg development Foxp3 CD25 (part of IL-2R) CD4
- 48. Regulation of Immune Responses regulatory mechanisms: Tregs Induced Tregs CD4+CD25+Foxp3+ cells induced by antigen CD25 (part of IL-2R) CD4 CD4 T cells antige+IL-10 TGFb Foxp3 Treg cells
- 49. Cytokines and Oral Diseases bacterial colonization periodontal disease (PD) bacterial invasion osteoclast formation/bone loss host responses chemokines: bone resorption, osteoclast survival IL-1: up-regulated, stimulates bone loss IL-6: proinflammatory to bone resorption TNFa: induces cytokine production, stimulate inflammation and bone loss RNAKL: inducer of osteoclast formation and activity, bone loss
- 50. Colony stimulating factors (CSFs) hematological disorders associated with cancer therapy Erythropoietin (EPO) anemia associated with kidney disease IFN-b multiple sclerosis IFN-g chronic granulomatous disease (GCD) IL-2 kidney cancer, melanoma IL-11 thrombocytopenia following high dose chemotherapy TNFa mAb Infliximab for rheumatoid arthritis and Crohn’s disease Cytokines and Clinical Applications
- 51. Cytokines properties, categories, signaling, function What are cytokine? Interleukines, chemokines, monokines, … cytokine receptors NFkB, JAK/STATA, chemokine signaling pathways role of cytokines in immunomodulation cytokines and oral diseases (PD)