S3M1-immuno – Flashcards
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| First antibody secreted in an immune response. Presence of this antibody indicates that antigenic exposure is a recent event. Secreted as a pentamer with five identical units joined by a J chain. It is a large molecule with 10 binding sites. Binds very strongly to pathogens with repetitive epitopes. Powerful activator of hte complement system. What is it? |
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| IgM |
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| This is the second antibody to be secreted. It is secreted in very large amounts and has a longer half life than the "early antibody". It is the most abundant antibody in the blood and lymph. Has 4 subclasses. What is it? |
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| IgG |
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| These two sublcasses of IgG readily cross the human placenta and NK cells express an Fc receptor, CD16, which is specific for the same two sublcasses of IgG. Name these two subclasses. |
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| IgG1 and IgG3 |
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| This antibody occurs as a monomer and as a dimer. The monomeric form is secreted into the bloodstream and the dimeric form contains a j chain and secretory component. It is transported across the epithelium and found in the lumen of the gut as well as in secretions and on mucus membranes. More of this antibody is produced in the gut than all other Ig from other sources combined. It is believed to play a role in eosinophil degranulation. There have also been trimeric and tetrameric forms of this antibody. Which antibody is this? |
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| IgA |
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| This antibody bind to high affinity receptors on mast cells and basophils and plays a major role in the pathogenesis of allergic rxns. Involved in the immune response against helminthic parasites |
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| IgE |
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| this is the least understood immunoglobulin. It has no known function when secreted. but it is expressed on the surface of B cells and with IgM it acts as the B cell receptor for antigen. |
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| IgD |
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| PAMP of TLR 2 |
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| gramp positive peptidoglycan |
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| PAMP of TLR 3 |
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| dsRNA remember that TLRs bind microbial prokaryotic structuers |
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| PAMP of TLR 4 and its mediators (2 co-factors) |
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| LPS= endotoxin of gram negative bacteria. Mediated by CD14 and MD2 |
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| PAMP of TLR 5 |
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| flagellin |
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| PAMP of TLR 6 |
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| mycoplasmal lipopeptide |
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| PAMP of TLR 7 |
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| ssRNA and Imidazoquinoloines (antiviral compounds) |
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| PAMP of TLR 9 |
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| bacterial DNA |
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| PAMP of TLR 1 |
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| bacterial lipopetide |
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| IL-1 activity |
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| Pyrogenic which means that it induces fever (this implies that it has endocrine activity since it travels far to hypothalamus for fever induction) and pro-inflammatory induces IL-6 production |
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| IL2 |
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| activation fo NK cells, T cells and B cells and macrophages |
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| IL-6 |
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| Pyrogenic (fever induction so has endocrine capability) and pro inflammatory. Also induces actue phase protein production (it is made when macrophage ingests an organism, IL-6 wil act on hepatocytes to induce the production of the acute phase proteins: mannose binding protein, fibrinogen, and c-reactive protein) also i nduces T and B cell proliferation |
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| IL-8 |
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| chemoattractant(in the skin it is secreted by karatinocytes to attract neutrophils in the innate response) it also up regulates the expression of adhesion molecules |
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| IL-12 |
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| activation of NK cells |
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| TNF alpha |
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| Induces IL-1 and PG-E2 synthesis and also induces production of acute phase proteins |
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| INF |
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| posesses anti-viral activity |
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| What is the Fc receotor that binds IgG on NK cells? |
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| CD16 when it binds IgG(which is already bound to the viral ag), then there is activation of the K function (NK activation) and expression fo the FasL to bind Fas+ cell which causes the release of perforins and granzyme to induce apoptosis Note: Engagement of the Fas system leads to cell death) |
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| Which CD expressed by NK cells is unique to NK cells? |
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| CD56 (note: NK cells also express CD2) |
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| waht are 4 activators of the NK cell? |
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| 1. IL-12 2. INF-alpha 3. INF-beta 4. TNF-alpha |
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| wehat is an adjuvant? |
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| a material that enhances mmunogenicity e.g. alum |
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| what are the 3 phases of the antigen elimination curve? |
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| for IV injected antigen 1. equilibrium phase-time required for equlibration of antigen with tissue and fluids, antigen removed during this phase can be found in liver spleen and lung 2. catabolic decay phase; 4-7 days; antibody is being produced but not detectable, this is antigen removal phase 3. immune elimination phase; accelerated removal due to binding of newly formed antibody with antigen, possible to detect free circulating antibody. |
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| How do host cells protect themselves from MAC cytolysis? |
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| CD59= protectin=HRF protects the host cell from lysis by inhibiting mac formatin even if C5bC6789 attaches to the host cell. |
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| Which complement factors promote chemotaxis for neutrop[hils and monocytes? |
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| C3a and C5a also C567 |
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| Which complement products participate in immune adherance where they enhance adherance of phagocytes to vascular endothelium during the process of phagocyte mobilizatin? |
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| C3a C5a (which are also chemotactic factors) |
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| Which complement activatin products possess anaphylatoxin activity, which increases vascular permeability, smooth muscle contraction and mast cell degranulatin. These changes make it easier for antibody and cells to leak out of hte blood into the site of an infection. the increased fluid in the tissues also enhances the migration of presenting cells to local lymph nodes. List the factors in order of increasing magnitude of anaphylatoxin acitvity |
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| C5a>C3a>C4a |
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| Which complement receptor is a member of the B cell co-receptor complex that will increase the signal transduction |
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| CR2 which is also CR21 |
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| Which compliment receptor is absolutely necessary for immune complex clearance? |
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| CR1 |
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| which complement receptor binds m, rbc, b cells, granulocytes? |
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| CR1 |
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| Which complement receptor binds B cells (b cell activationn) |
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| CR2 (CD21) |
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| which complement receptor binds m, m0, and granulocytes(which play a role in opsonization) |
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| CR3 |
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| which complement receptor binds plt? |
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| CR4 |
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| Which cytokines interfere with virus replicatin but do not stop the infection? |
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| Inteferons: INF alpha, inf beta, inf gamma |
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| Which cytokines are colony stimulating factors i.e. promote hemopoiesis? |
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| G-CSF (granulocytes) M-CSF (macrophages) GM-CSF (granulocyte/macrophage) SCF (differentiation of BM stem cells) IL3 IL6 IL7 IL11 |
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| chemotactic cytokines? |
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| RANTES (regulated on activatin normal t cell expressed and secreted) Eotaxin (eosinophil selective) IL-8 SDF-1 |
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| Overproductin of IL-1 and TNF-alpha can result in which two cytokine related diseases>? |
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| bacterial septic shock (macrophage overproduction of hte two cytokines and toxic shock syndrome (superantigen induced polyclonal t cell activation and overproductin of the two cytokines) |
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| what are the classic symptoms of septic shock? |
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| hypotension, fever, diarrhea, and DIC (dissiminated intervascular coagulation) |
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| Which cytokine stimulates profliferatin of plasma cells possibly contributing to uncontrolled cell proliferation? |
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| IL6 |
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| decreased CMI due to reduced expression of IL-2R causes immune supression ... indicated which disease? |
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| Chagas |
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| Produced by various cells Used in the treatment of chronic hepatitis and Kaposi’s Sarcoma Inhibits viral replication, suppresses cell proliferation |
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| INF Alpha (roferon) |
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| Produced by many leucocytes and by fibroblasts Used in the treatment of Multiple Sclerosis Antiviral activity Cytostatic for tumor cells Stimulation of B cells Pyretic |
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| INF beta (avonex) |
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| INF-? (Actimmune®) |
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| Functionally distinct from INF-? and INF-?. Acts as a messenger between TH cells and phagocytes. Used in the treatment of CGD Produced by TH cells (main source) in response to IL-2 or Ag stimulation NK cells CD8+ cells Phagocytes In vitro effects: Antiviral activity Cytostatic for tumor cells Activation of phagocytes Superoxide ion production (^intracellular killing) MHC Class II expression Activation of endothelial cells Pyretic Induction of acute phase proteins Increased MHC expression |
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| A CC chemokine, like RANTES Produced by many cells CCR-3 receptor specific, eosinophil selective: attracts and activates eosinophils Synergistic activity with IL-5. IL-4 up-regulates VCAM-1 expression, ^eos migration |
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| Eotaxin |
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| Regulated on Activation, Normal T cell Expressed and Secreted A CC chemokine like eotaxin (with a double cysteine motif) Produced by many cells (lymphocytes, etc) Also known as CCL5, it binds to CCR5, a co-receptor for HIV, and can suppress HIV infection. Chemotactic for monocytes dendritic cells NK cells Eosinophils Basophils T cells Also activates these cells Possesses anti tumor activity Promotes CHAK formation (CC-chemokine activated killer) |
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| RANTES/CCL5 |
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| Secreted by activated lymphocytes, macrophages, neutrophils and NK cells Broad range of activities including IL-1 and PG-E2 synthesis by activated macrophages. Induction of acute phase protein production Expression of MHC antigens Receptors TNF-R1/TNF-R2 TNF-R1 contains a death domain; interacts with TRADD/FADD causing apoptosis Activates transcription factor NF-?B TNF-R2 also activates NF-?B |
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| TNF alpha |
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| Also known as lymphotoxin Expressed by and acts on many cell types. Similar in range and activity to TNF-? but less potent. Mitogenic for B cells |
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| TNF Beta |
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| IL-1? (membrane form), IL-1? (secreted form) Produced by activated APCs (B cells, dendritic cells, macrophages) Pyrogenic Many effects on various targets Activation of TH cells Proliferation of B cells Activation of NK cells Increased ICAM expression on vascular endothelial cells Chemotactic for macrophages and neutrophils |
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| IL-1 |
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| Produced by activated TH1 cells, which also express IL-2R Promotes growth of T cells Also acts on B cells, NK cells and LAK cells |
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| IL-2 (autocrine function) |
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| Produced by TH1 and TH2 cells Stimulates haematopoietic cells of multiple lineages Proinflammatory and mast cell stimulatory functions |
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| IL-3 |
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| Produced by activated TH2 cells and mast cells Affects activation, proliferation and differentiation of B cells Isotype switch inducing factor to IgG1 and then to IgE Also induces proliferation of TH2 cells Up-regulates MHC Class II expression on macrophages Stimulates growth of mast cells |
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| IL-4 |
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| Similar to IL-4 Synergistic activity with IL-4 for IgE production Induction of growth and differentiation of eosinophils |
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| IL-5 |
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| Similar properties with IL-1. Serves as a cofactor. Secreted by macrophages, BM stromal cells and lymphocytes Promotes proliferation and terminal differentiation of B cells Stimulates ab secretion by plasma cellsPromotes differentiation of myeloid stem cells Induces production of acute phase proteins by hepatocytes |
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| IL-6 |
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| Secreted by BM stromal cells and thymocytes Regulation of B & T cell development and maturation Induction of proinflammatory cytokines IL-1, IL-6 |
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| IL-7 |
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| Chemokine for neutrophils, T cells, basophils Promotes angiogenesis |
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| IL-8 |
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| Pleiotropic cytokine mainly produced by Th2 cells Stimulates cell proliferation and regulates hemopoiesis May be involved in asthma pathogenesis |
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| IL-9 |
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| Produced by activated T cells, primarily TH2, monocytes, mast cells Related to EBV Inhibition of proinflammatory cytokines from activated monocytes and macrophages Promotion of B cell proliferation |
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| IL-10 |
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| Produced by stromal cells Induction of haemopoiesis Production of acute phase proteins by hepatocytes (pro inflammatory) |
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| IL-11 |
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| Produced by activated APCs Promotes differentiation of TH0 > TH1 Costimulator of TH1 activity: expression of IL-2R, secretion of IL-2, INF-Enhances NK proliferation |
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| IL-12 |
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| Like IL-4, produced by TH2 cells and promotes IgE production Possesses anti-inflammatory properties |
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| IL-13 |
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| Hyperproduction promotes development of B-cell non-Hodgkin’s lymphoma. |
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| IL-14 (BCGF) |
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| Cytokines involved in B cell activation |
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| IL-1 IL-4 IL-6 IFN triggering: proliferatin of B cells, isotype/class switching. |
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| what does it mean when a B cell undergoes early class switch? |
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| some activated B cells will undergo an early class switching and differentiate immediately into antibody secreting plasma cells. Secrete IgM antibodies only, which contributes to the humoral response. |
