Three elemental R's of T-cell biology: repertoire, recognition, response Repertoire of clones Recognition phase Recognition of processed antigens: peptide-MHC o Cytokine production is one of the principal response of t cells to antigen recognition Activation phase Effector phase Response H1 (IFN-Y Clonal expansion H2(L-45,13) Functional differentiation TH17江立L-17) Memory TR1(IL-10) Tolerance to self Foxp3+T reg CTL
Repertoire of clones Recognition of processed antigens: peptide-MHC Response Clonal expansion Functional differentiation Memory Tolerance to self Activation phase TH1（IFN-g） TH2（IL-4,5, 13） TH17（IL-17） TR1（IL-10） Foxp3+Treg CTL Three elemental R‘s of T-cell biology: repertoire, recognition, response Effector phase Recognition phase Cytokine production is one of the principal response of T cells to antigen recognition
OT lymphocytes in response to Ags are the principal sources of cytokine in adaptive immunity The function of T helper cells is mediated by cytokines
⚫T lymphocytes in response to Ags are the principal sources of cytokine in adaptive immunity . ⚫The function of T helper cells is mediated by cytokines
What are cytokines? Inducing stimulus e Cytokines are polypeptides produced by the cells of innate Cytokine)Cytokine-producing cell and adaptive immunity in gene response to microbes and other antigens as a result of cellular activation Cytokine Cytokines initiate their actions by binding to specific membrane Receptor receptors on target cells Signal o The cellular responses to most Gene cytokines consist of gene Target cell activation activation, resulting in the expression of new functions and sometimes the proliferation of Biological effects the target cells Figure 12-1 Kuby IMMUNOLOGY, Sixth Edition o 2007 W.H. Freeman and Company
⚫ Cytokines are polypeptides produced by the cells of innate and adaptive immunity in response to microbes and other antigens as a result of cellular activation. ⚫ Cytokines initiate their actions by binding to specific membrane receptors on target cells. ⚫The cellular responses to most cytokines consist of gene activation, resulting in the expression of new functions and sometimes the proliferation of the target cells What are cytokines?
Cytokine actions may be local and systemic ●● Autocrine act on cytokine-producing cell itself action Paracrine action act on a nearby cell circulation Endocrine action act at a distance from the site of infection
Cytokine actions may be local and systemic Autocrine action Endocrine action circulation act at a distance from the site of infection Paracrine action act on a nearby cell act on cytokine-producing cell itself
Most cytokines act close to where they are produced c TLRS ⊙ u45 IL-10. IL- B Antigen Effector Naive cytokines T1 IFN-t APC IL-2. TNF. L12.LL·18 Activation O T lymphocytes often secret cytokines at the site of contact with antigen-presenting cells
⚫ T lymphocytes often secret cytokines at the site of contact with antigen-presenting cells . Most cytokines act close to where they are produced