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Immune effector function. Induction of adaptive immunity Differentiation of Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory. Foreign Ags………. 對外. Gene rearranged receptors: TCR/BCR. Adaptive immunity. Four characteristics. 1. Antigen specificity 2. Diversity
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Immune effector function Induction of adaptive immunity Differentiation of Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory
Foreign Ags………. 對外 Gene rearranged receptors: TCR/BCR
Adaptive immunity Four characteristics 1. Antigen specificity 2. Diversity 3. Immunological memory 4. Self tolerance
Clonal selection Immune diversity Antigen specificity Diversity Memory Central tolerance Peripheral tolerance
Sites of effector function Primary (Central): Bone marrow 骨髓 Thymus 胸腺 Secondary (Pheripheral): Lymph nodes 淋巴結 Spleen 脾臟 Peyer’s patches
Lymph node distribution in the body
Immunity & Ag location Humoral response Ag Innate Adaptive Extracellular Phagocytes B cells Intracellular NK CD8 Tc cells (Altered self) 2 CD4 Th 1 Cytotoxicity Cell-mediated immunity (CMI)
Induction of adaptive immunity Phagocytes Inflammation Dendritic cells (DC) Antigen-Presenting Cells (APC) Lymph node B/T cells Lymphocyte activation Clonal selection Humoral Imm/CMI Memory Inflammatory site Inflammatory site
T cell activation DC HEV Lymph node T
Immune effector function Induction of adaptive immunity Differentiation of CD4 Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory
Naïve, activated, effector Activation Effector Cell-mediated immunity (CMI) Humoral immunity
Priming The activation and differentiation of naïve T cells Three signals in naïve T cell activation Costimulation
Signal 1 Ag & MHC presentation pathways Foreign or Self Ag DC/Macrophages/B cells
Signal 2 Signal 2 alone
Signal 1+2 CD4 T cell activation IL2R IL2 production Clonal expansion
Lack of signal 2 upon T cell activation Peripheral tolerance
Negative regulation of signal 2 upon T cell activation Inhibition of activated T cells Peripheral tolerance
CD4 T cell differentiation Th17 Promote local inflammation CMI: CD8 T Humoral response
Immune effector function Induction of adaptive immunity Differentiation of Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory Effector response
Activation Innate immunity Effector phase
Rapid T cell response to infection: Th17 Amplifier of acute Inflammation (local site, BM) IL17 Ubiquitous expression of IL17R: fibroblasts, epithelial cells, keratinocytes, etc. G-CSF GM-CSF IL6 Chemokines Recruitment of neutrophils Expression of antimicrobial peptides Activation of macrophages
CD4 T cell differentiation CMI Humoral immunity CD8 T
CMI: Macrophages activated by Th1 APC activation
CMI: CD8T cytotoxic response Cytotoxic granules
Membrane effector molecule
Immune effector function Induction of adaptive immunity Differentiation of Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory Effector response
B cells as APC Effector Th2 cells Humoral immunity: B cell response
CD4T-dependent: 1. Isotype switching 2. Somatic hypermutation Affinity maturation 3. Memory
Effector response CD4 Th17, Th1/ Th2 CD8 Tc B cells
Immune effector function Induction of adaptive immunity Differentiation of Th Cytokines Cell-mediated immunity Humoral immunity Immunological memory
Adaptive immunity
Protective immunity & time Memory cells:long-lived Apoptosis of effectors