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86 Cards in this Set
- Front
- Back
Immune system |
-protect us from infections |
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If an individual will be diseased or not depends on... |
immune system strength and amount of attacking pathogens. |
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immune system failure occurs |
when amount of pathogens and their virulence/pathogenicity exceed the ability of immune system. |
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Innate immune system |
non specific, first line of defense, generic |
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Adaptive immune system |
acquired, B & T cells, context with pathogen induces specific clones, immunological memory, basis of vaccination |
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Non-cellular innate system effectors |
cytokines (interferon) and complement |
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Cellular innate system effectors |
Macro-phages and other phagocytes, nk cells |
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Non cellular effectors of the adaptive immune system |
Antibodies |
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Cellular effectors of the adaptive immune system |
T cells (CD4, CD8) |
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Two main parts of blood |
Plasma and elements |
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What are the "elements" blood |
White blood cells, red blood cells, platelets |
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White blood cells (leukocytes) can be divided into what two categories? |
Granulocytes and A granulocytes |
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Granulocytes |
- type of white blood cells that include: Neutrophils, basophils, Esinophils |
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Agranulocytes |
- A type of white blood cells that include Monocytes, and lymphocytes |
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Lymphocytes |
A type of Agranulocyte which includes, T cells, Bcells, and NK cells
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Dendritic cell |
A white blood cell in the category of agranulocyte and is the initiator of the adaptive immune response. |
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Plasma cells |
are "descendants" of B cells which produce antibodies |
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T cell function |
cell mediated iimmunity |
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Natural killer (NK) cells |
Destroy target cells by cytolysis and apoptosis |
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Monocytes |
- A type of whit blood cell in the category of Agranulocyte which performs phagocytosis when they full mature into macrophages |
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Neutrophils |
make up about 60-70% of white blood cells. Phagocytes. |
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Basophils |
Make histamine |
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Eosinophils |
Production of toxic proteins against certain parasites and some of them are phagocytes. |
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Immune responsive cells of the innate immune system |
Monocytes, Granulocytes, Lymphocytes |
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Monocytes are located in |
the circulatory system and tissues |
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In response to inflammation signals, monocytes can |
move quickly to sites of infection in the tissues and divide/differentiate into macrophages and dendritic cells |
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Macrophages |
- Found in the circulatory system and tissues, possess surface receptors for manosse and fructose, recognize common surface antigens like LPS, perform phagocytosis |
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Dendrite cells |
Found on the surface of structures like skin and mucous membranes. Star-like shape, surface recognition via PAMPS, phagocytosis followed by migration to lymphoid tissues |
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Neutrophils (PolyMorphonuclear Neutrophils: PMN's) |
Mainly Phagocytes, more than 60%. Granules contain lytic enzymes and antimicrobial substances
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Eosinophils |
-No phagocytic, inflammatory reaction, and allergic reaction, Parasitic infection ( relsease of ROS)
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Basophils |
Not phagocytic, inflammatory reaction and allergic reaction, |
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CD4 |
helper T cells |
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CD8 |
Cytotoxic T cells |
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Steps of phagocytosis |
1. Ingestion through phagoccytosis , and phagosome is formed. 2. The fusion of lysosomes with the phagosome creates a phagolysosome, the pathogen is broken down by enzymes 3. Waste material is expelled or assimilated. |
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What is the cause of acute inflammation? |
Common pathogens or allergens |
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Cells that are involved in acute inflammation |
Granulocytes and monocytes |
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Mediators of acute inflammation |
Amines and Eicosanoids |
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Eiosanoids |
Long fatty acid that acts on inflammatory pathways |
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Onset of acute inflammation |
immediate ( results noticed in a couple of minuets) |
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Duration of acute inflammation |
Few days to a couple of weeks |
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Outcomes of acute inflammation |
Heal, abscess formation, or chronic inflammation |
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Cause of chronic inflammation |
Non-degradable pathogens (virus) |
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Cells involved in chronic inflammation |
Monocytes, Lymphocytes |
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Mediators of chronic inflammation |
Cytokines and ROS |
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Onset of chronic inflammation |
Delayed ( an acute phase if presents is usually not noticed) |
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Duration of chronic inflammation |
Months to years |
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Outcomes of chronic inflammation |
Tissue destruction and necrosis |
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Lysozymes break what kind of bonds? |
Glycosidic bonds |
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Glycosidic bonds are found... |
between sugar monomeric units |
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Amount of digestive enzymes found in a lysosome: |
about 50 |
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Influx of immune-active components to the site results in |
inflammation/tissue swell |
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The major function of the innate immune system |
recruiting immune cells to the site of infection by producing chemical factors and specialized chemical mediators called cytokines. |
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Chemical mediators involved in the immune system |
Cationic proteins, complement system, cytokines |
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Cationic proteins |
carthelicidin, defensins; usually ionophores which alter membrane permeability of pathogens; glycoproteins |
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Complement system |
Glycoproteins; inserted into bacterial membranes resulting in lysis, facilitates antibody recognition which results in opsinization, attracts macrophages and neutrophils through chemotaxis, |
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Cytokines |
Glycoproteins and proteins; signal molecules secreted by almost every nucelated cell, includes interluekins and inerferons |
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Three pathways of complement action |
alternative pathway, MB lectin pathway, and classic pathway |
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Classic complement pathway acctivation |
binding of antibodies formed during the adaptive immune response |
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Mannose binding lectin ( Mb lectin) complement pathway activation |
Lectin binds to mannose which is a common surface component of bacteria, fungi, and some enveloped viruses. This opsonizes the pathogen and enhances phagocytosis. |
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Alternative complement pathway activation |
Bacterial cell wall components with repetitive surface structures like LPS; formation of membrane attack complex which is inserted into the pathogens membrane. |
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Complements are found in _______ and made by __________. |
the circulatory system, liver |
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Formation of ionic pores by cathelicin and defensins cause |
disruption of the electron transport chain which results in the organism losing energy and motility. |
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Antigen |
Any substance that can stimulate an immune response but not necessarily its entire structure is immunogenic. |
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If a antigen is to large |
it is processed into small epitope units |
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If an antigen is too small |
carrier proteins called heptans enhance recognition |
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Epitopes |
Sub-region/structure of an antigen that is the actual antigenic determinants. |
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Major histocompatibility complex: |
distinguish between self and non-self. Exists on the surface of almost all human cells. participants in antigen processing. |
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MHC1 |
found on almost all cells. Mostly respond to viral infections. Present proteins found within the cytoplasm of the cell. |
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Events of viral infection detection involving MHC1 |
viral invaison > cviral protein digestion > presents as MHC 1 viral protein complex on the surface of the cell > recognized by CD8 cells > cytotoxic T cell activation |
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MHC 2 |
- found on leukocytes (macrophaages, dendrite cells, some B and T cells), recognized by helper T (CD4) cells, presents contents found in the extracellular space |
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Process of MHC 2 presentaion |
Extracellular pathogen > phagocytosis and digestion > presents as MHC2 digested protein fragment complex > recognized by Th CD4 cell, helper T cell activation > Tjh clonal multiplication |
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Cytokine procuction from T cells modulates |
both specific and non specific host defenses |
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T cell response steps |
Recognition of peptide epitope from MHC complex, Production of cytokines, Direct killing (cytotoxicity) of foreign cells and infected host cells. |
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B cell response steps |
Antigen triggering from monomeric IgM, production of Ab |
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T cell dependents B cell activation |
triggered by small foreign proteins, strog response, production of memory cells, boosted by immunization |
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T cell independent B cell activation |
Triggered by large repeating surface structure like polysaccharides, weaker response, lower antibody affinity to antigens, no memory cell production, does not produce effective immunization |
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What antibody is usually secreted first? |
Pentameric IgM |
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IgG |
usually secreted second and is more specific that the primarily secreted antibody |
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IgA |
Has a dimeric structure |
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FAB |
contains variable region for antigen binding |
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Fc |
contains constant region, effector function, interaction with complement components, interaction with phagocytes. |
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Adverse effect of the immune system |
Tolerance: self antigen recognition due to the non fool proof mechanism which can be disrupted by genetic disposition, chronic infection, drugs and toxins, these can be organ specific or systemic |
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Type one Hypersensitivity reaction: Immediate Hypersensitivity |
caused by reexposure to an antigen, the mediator is histamine from mast cell, and the antibody involved is IgE |
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Type 2 hypersensitivity reaction: antibody mediated |
caused by antibody misbinding on host cells (Molecular mimicry), mediators are recruitment of phagocytic cells and cytotoxic T cells, antobodies involved are IgG and IgM, and some examples would be auto immue haemolytic anemia, acute rheumatic fever, |
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Type 2 hypersensitivity reaction: Immune complex |
Caused by Excessive Ag-Ab complexes, mediators are the non cleared Ag-Ab complexes which eventually deposit in blood vessels, joints and organ, antibodies involves are IgG and some examples would be Lupus and Reactive arthritis |
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Type 4 hypersensitivity reaction: Delayed type |
Hyper activated macrophage ( secreting too much TNF), mediated y TNF recruiting monocytes which create wall off but with significant local damaged, no antibodies are involved, and some examples would be Rheumatic arthritis and Chron's disease. |