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134 Cards in this Set
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- 3rd side (hint)
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what does encapsulation do?
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prevents opsonization by antibodies (recognition and binding)
prevents microorg from bing phagocytized |
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what kind of bacteria can have endotoxins? (
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gram negative bacteria
i.e. enterobacteria |
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describe exotoxins
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polypeptides produced and released by organisms
antigenic, toxic, unstable in heat bind to receptors in target organs, interfere with metabolic processes |
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describe endotoxins
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immunogenic part of lipopolysaccharide bacterial cell wall that triggers a massive immune response when bacterium lyses - immune response leads to cell shock and multiple organ failure
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what are the characteristics of retroviruses
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contain encoding information for reverse transcriptase enzyme to create mRNA and DNA from own genome
DNA replicates when host cell replicates |
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lactoferrin
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mucosal protein which reduces Fe+3 availability and limits bacterial growth
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describe some chemical barriers of our epithelium
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acidic environment of skin, urine, and vagina inhibit bacterial growth
saliva, mucus, tears, and sweat contain a bacterial killing enzyme sebaceous gland secretions are antifungal |
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describe innate immunity
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does not require a previous exposure to the offender to react. It is our first line of defense and works very quickly. Its response is usually local (ex: if you get a splinter in your finger. Innate immunity begins the process of reacting to the foreign invader).
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what is the defining cell associated with innate immunity?
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Natural Killer cell
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what is another name for natural killer cells?
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describe the first step that happens in the innate immune response after penetration/invastion by a foreign antigen
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first, the Ag is detected by an antigen presenting cell (APC) which is a macrophage
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after the Ag is detected by the APC, what happens in innate immune response?
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the Ag is phagocytized by the antigen presenting cell (APC)
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after the Ag is phagocytized by the APC, what happens in the innate immune response?
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within the APC, the Ag is loaded onto MHCII, a protein molecule that tells the body that this is not self
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after the Ag is loaded onto MHCII, what happens in the innate immune response?
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the MHCII-antigen complex is displayed at the cell surface, and the APCs travel to the Lymph node, where T helper cells (CD4+) can detect them. Also in the lymph node, antigen is presented to CTL/Natural Killer T- cells/CD8+
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If the T-cells recognize the Antigen as foreign, then what happens?
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the helper Tcells "HELP' turn on the B Cells, and the helper T cells activate the killer T cells
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after helper and Killer T-cells are activated, what happens in innate immue response?
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active helper and killer T-cells replicate, including formation of memory cells, which can responds quicker to subsequent infection by that kind of pathogen
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what do the killer t cells do?
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they seek and destroy the antigen and execute "lethal hits" causing apoptosis
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what is the alternative pathway?
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if the antigen is bacterial endotoxin with lipopolysaccharide cell wall (gram - cells) then the complement is activated via the C3a alternative pathway - complement cascade leads to membrane attack complex (MAC) which kills the Ag cells.
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In adaptive immunity, antigens in the blood trigger what?
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b-cell activation, but only if the b-cell recognizes the specific antigen. Active helper T-cell is required for B-cell activation
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If helper T-cells recognize a specific antigen presented by a macrophage (APC), then the Helper T-cell activates the
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B cell
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What does the activated B-cell do?
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replicates and produces antibody molecules that can bind to specific antigens
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what happens when the antibody molecules bind to specific antigens?
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Stimulates the complement via the C1 "Classical" pathway.
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what are steps to the C1 "Classical" pathway?
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Precipitation
Neutralization - inflammation Opsonization MAC |
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Memory B cells come from where?
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from the activated B-cells
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what else does the antibody-antigen complex signal?
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phagocytosis
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describe what happens in adaptive immunity in the case of virus infection
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nucleated cells are infected by the virus, which are then loaded to MHCI. Natural killer cells (Killer T cells) read the complex as foreign, give the virus infected cell a "lethal hit"
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what are the two categories of leukocytes?
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granulocytes and agranulocytes
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what types of cells derive from granulocytes?
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neutrophils: macrophage
eosinophils: macrophage basophils: mast cells |
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what types of cells derive from agranulocytes?
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lymphocytes: B and T cells
Monocytes: immature, become macrophages in tissues |
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what are the lymphocytes?
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B and T cells
agranulocytes |
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GRANma POLY uses a NEBulizer
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Granulocytes/polymorphonuclear
Neutrophils Eosinophils Basophils |
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where do T cells mature?
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Thymus
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where do B cells mature?
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bone marrow
and then the lymph node |
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Primary organs in the immune system?
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Bone marrow
Thymus |
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Secondary organs in the immune system?
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lymph nodes
spleen tonsils Peyer patches in intestine |
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what are the primary effectors of the immune system?
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Leukocytes = White Blood Cells
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monocytes from the circulating blood migrate to organs and tissues to become ______
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macrophages
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wgat do neutrophils primarily respond to?
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acute bacterial infections
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what do eosinophils primarily respond to?
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allergic reactions and infection by intestinal parasites (kill parasitic helminth through release of specialized molecules)
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what is required for a macrophage to engulf an offender
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the macrophage must recognize it as non-self?
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what is the difference between mast cells and basophils?
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basophils become Mast cells, However, basophils are called basophils when they are circulating in the vascular system. Mast cells are found in tonnective tissues
mature basophils can migrate to connective tissue and do not reenter the curculation (called mast cells once in the tissue) |
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what is the function of mast cells and basophils?
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Begin the inflammatory response.
when an appropriate stimulus occurs, such as antigen binding to the IgE antibodies, mast cells and basophils release granules (degranulate) containing proinflammatory chemicals. (histamine, platelet activating factor, vasoactive amines) |
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what is the role of cytokines secreted by macrophages
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macrophages secrete a variety of cytokines that induce inflammation (i.e. interleukins) and chemotaxis. Some macrophage cytokines stimulate the growth and defferentiation of other white blood cell types
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what are the three major types of lymphocytes?
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NK cells, T cells and B cells
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NK cells function in _______ immunity wheras B and T lymphocytes are the cells responsible for __________immunity.
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innate
specific adaptive |
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CD4+ cells (T helper cells) do what?
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interact with antigens presented on the surface of specialized antigen presenting cells such as dendritic cells, macrophages, and B cells. Secrete cytokines that activate other T cells and macrophages, and stim b-cell proliferation adn antibody production
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what do CD8+ cells (cytotoxic T Cell (CTL) do
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require "help" from T helper cells to activate fully. kill through perforins and CD95 (intracellular enzyme cascades)
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what is lactoferrin
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Lactoferrin is one of the components of the immune system of the body; it has antimicrobial activity (bacteriocide, fungicide) and is part of the innate defense, mainly at mucoses.[1] In particular, lactoferrin provides antibacterial activity to human infants.[2
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what is reverse transcriptase
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a reverse transcriptase, also known as RNA-dependent DNA polymerase, is a DNA polymerase enzyme that transcribes single-stranded RNA into double-stranded DNA. It also helps in the formation of a double helix DNA once the RNA has been reverse transcribed into a single strand cDNA. Normal transcription involves the synthesis of RNA from DNA; hence, reverse transcription is the reverse of this.
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where to T-cells mature?
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thymus
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where do b cells and natural killer cells mature
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in the marrow
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what happens in the lymph node?
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contain large numbers of b cells, t cells , and macrophases
lymph fluid flows through for immune cells to filter, detect and react to foreign material |
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what do white blood cells in general do?
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mediate inflammation and immunity
locate and eliminate pathogens and foreign molecules. |
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what are the signaling molecules?
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cytokines, chemokines, and kinins
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degranulation of basophils and mast cells begins
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inflammatory response associated with allergic reactions and wound healing
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what do dendritic cells do
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similar to macrophages
summoned by cytokines/chemokines engulf antigen bring it back to lymph node to show antigen to B and T cells |
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dendritic cells are activated by the
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innate response
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what do macrophages do?
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ingest invading microorganisms,
capable of cell division Proliferate at site of inflammation |
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what are monocytes
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mononuclear
immature macrophages that circulate in the bloodstream become macrophages when they enter the tissues |
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macrophages secrete _________ that induce _______ and chemotaxis
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cytokines
inflammation |
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the surface of macrophages are covered with a variety of ________
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receptor proteins
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Fc receptors on macrophages bind to:
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the constant fragment of antibodies
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macrophages present ________ to what, where?
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antigens
b and c cells lymph node |
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describe what Natural Killer (NK) cells do.
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effectively kill tumor and virally infected cells without previous exposure
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NK cells use Fc receptors to recognize
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antibody-coated cells
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Fc receptors are the what?
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constant "handle" on an antibody that allows binding
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what are the two major classes of T lymphocytes and how are they differentiated?
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T helper cells: have CD4 proteins
Cytotoxic T-cells: have CD8 proteins |
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what do B lymphocytes do?
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produce antibodies; have antibody-like receptors on cell surface
carry many copies of identical b-cell receptors respond to only one antigen epitope The antigen epitope must fit the b-cell receptor for activation |
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what is "epitope"
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the specific shape of the antigen.
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what are the two different complements?
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Classic Pathway
Alternative Pathway |
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the Classic pathway is initiated by
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an adaptive response
Ag/AB complex |
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the alternative pathway is initiated by
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an innate response
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what is the end result of the complement?
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n matter the trigger, the end result is always a membrane attack complex. The attack causes Na+ and water to flood the offender, causing it to burst
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Kinins cause what?
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powerful vasodilation response
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what are the three purposes of inflammatory response?
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Neutralize and destroy invading and harmful
agents Limit spread of harmful agents to other tissue Prepare damaged tissue for repair |
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what are the five cardinal signs of inflammation
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Redness
Swelling Heat Pain Loss of function |
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what are the two types of inflammation?
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Acute
Short in duration, lasting less than 2 weeks Involves a discrete set of events 85 Chronic More diffuse Extends over longer period May result In scar tissue formation or deformity Fact: inflammation has now been linked to many pathologic processes, including CVD, diabetes, and insulin resistance. It remains to be demonstrated if inflammation is causitive to these and other pathologies |
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what is the role of vasodilation in inflammation?
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allows for the emigration of neutrophils and macrophages into tissue
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vasodilation in tissues leads to what?
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pain, heat, redness
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what are the three players in healing
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fibroblasts
endothelial cells myofibroblasts |
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what are the four kinds of exudate
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serous exudate - serosanguineous
fibrinous exudate - sticky, thick purulent exudate - pus hemorrhagic exudate - RBC's mixed in with serous fluid: can be a sign of severe inflammation |
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what are the funxtions for inflammatory exudates
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Transport leukocytes and antibodies
Dilute toxins and irritating substances Transport nutrients for tissue repair |
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what are the signs of systemic inflammation?
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Systemic
Fever, neutrophilia, lethargy, muscle catabolism Acute phase proteins Erythrocyte sedimentation rate (ESR |
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what is the general role of specific adaptive innumity?
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Recognizing foreign invaders
Destroying foreign invaders Retaining memory of the encounter 96 g y Allows for more effective defense (adaptive) to be achieved after subsequent exposure |
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what is MHC and what is another name for it?
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major histocompatibility comples
aka human leukocyte antigen (HLA) complex |
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what are MHCs?
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a cluster of genes on chromosome 6. the proteins made by these genes are displayed on the surface of body cells and mark them as "self"
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class I and II MHC genes code for proteins that
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display or "present" antigens on the surface of cells
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MHC classes 1 and 2 do what
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codes for proteins that present antigens on cell surface
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describe the MHC class I presentation
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Found on every cell in the body
Nucleated cells continuously produce MHC I proteins on endoplasmic reticulum; combine with peptide fragments in cytoplasm MHC I peptide complexes cycled to cell surface; 99 inspected by T‐cells (cytotoxic T cells) |
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what happens if there are abnormal proteins presented on MHC class i
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produce immune response
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describe MHC II presentation
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MHC II Proteins
Found ONLY on B cells, macrophages, Ag presenting cells (like DC) Present antigens obtained from extracellular sources Extracellular antigens must first be ingested by antigen‐presenting cell 101 g p g Antigen presenting cell degrades into fragments in endocytic vesicle T‐helper cells ‘read’ the Ag and activate B cells to begin cranking out antibodies MHC II proteins synthesized on endoplasmic reticulum Pick up antigen from phagosome on way to plasma membrane |
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t cell receptors are used to:
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recognize foreign antigen displayed on
surface of antigen‐presenting cells T cells are specific O l i d d i l i i Only recognize and respond to a single antigenic epitope |
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what do t helper cells do (CD4)?
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Recognize antigen in association with MHC II
molecules CD4 protein necessary to enable T helper cells to bind to MHC II protein; T‐cell receptors i ifi ti t d 104 recognize specific antigen presented T‐cell receptors bind to corresponding antigen and generate signaling cascade in T helper cell cytoplasm T‐cell receptors linked to cascade through CD3 |
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what do cytotoxic t cells (CD*) do?
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Recognize antigen displayed in association with
MHC I protein CD8 protein needed for MHC I binding TCR specifically recognizes presented antigen Bi di Cytotoxic T Cells (CD8+) 106 Binding Triggers responses in cytotoxic T cells similar to that of T helper cells Not enough to activate them (need costimulation by IL‐2 cytokines) Costimulators usually present on surfaces of presenting and responding cells |
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what do activated cytoxic t cells do? How?
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Proliferate into memory cells and effector cells
Perforins Proteins manufactured in cytotoxic T cell Cytotoxic T Cells (CD8+) (Cont.) 108 Store in cytoplasm granules with granzymes Granules Bind to target cell, migrate to contact site, and release to target cell membrane |
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how do perforins work
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Perforins
Assemble into pores, allow granzymes into target cell, degrade DNA, trigger apoptosis CD95 or FAS ligand—CD95 protein on cytotoxic Cytotoxic T Cells (CD8+) (Cont.) 109 T cell Binding to CD95 protein to CD95 ligand causes cell death |
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describe memory b cells
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Memory B Cells
Contain antigen receptors Memory of exposure to an antigen is stored in memory B cell clones |
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describe plasma b cells as short-lived antibody producing factories
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Plasma B Cells: Short‐Lived Antibody
Producing Factories All plasma cells in clone secrete antibodies with identical monoclonal antibody; secretions 112 circulate in blood/body fluids Bind specifically to antigen that triggered its production Usually die off once antigen is cleared; some live to recognize antigen if re‐exposed |
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eacdh b cell receptor is coded for two types of genes:
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Each B‐cell receptor coded for two types of
genes Variable region Makes up antigen‐binding site 113 Constant region Same for all antibodies of a given class Structure similar to IgM |
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what are the five classes of antibodies
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G, M, A, D, E
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describe IgG
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Most common type
120 Smallest Easily escapes bloodstream to enter interstitial fluid |
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describe IgM
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10% of circulating immunoglobulins
Mostly found in intravascular pool; cannot penetrate capillary wall 121 First to be produced on exposure to antigens or after immunization Major antibody found on B‐cell surfaces Works best to activate complement |
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describe IgA
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Produced by plasma cells located in tissue under
skin/mucous membranes Primarily found in saliva, tears, tracheobronchial secretions colostrum milk 122 secretions, colostrum, breast milk, and GI/GU secretions Secretory IgA Complex made by binding to secretory component produced by epithelial cells Allows transport of IgA into secretions IgD |
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describe IgD
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Found in tiny amounts in serum
Located primarily on B cell membranes (with IgM) Thought to be cellular antigen receptor that acts Antibody Structure (Cont.) 123 to stimulate B cell to: Multiply Differentiate Secrete other specific immunoglobulins |
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describe IgE
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IgE
Bound by Fc tail to receptors on basophil and mast cell surfaces Trace amounts identified in serum Helps in immunity against helminthic parasites; Antibody Structure (Cont.) 124 responsible for initiating inflammatory and allergic reactions Functions as signaling molecule Causes mast cell degranulation when antigen detected at mast cell surface |
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what are the fxns of antibodies
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Precipitation, agglutination, neutralization,
opsonization, complement activation Each arm of immunoglobulin Y structure can bind an antigenic epitope All tib di d ti t bi d t th 126 Allows antibodies and antigens to bind together into large insoluble complexes that precipitate out of body fluids Can function as antitoxins Neutralize bacterial toxin Antibodies bound to foreign antigens on cell membranes 128 Can also activate complement cascade Can trigger Chemotaxins Inflammatory mediator release Membrane attack complex formation |
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describe passive immunity
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Transfer of plasma containing preformed antibodies
against specific antigen from a protected or immunized individual to an unprotected or nonimmunized individual 129 B‐cell immunodeficiencies Following exposure of individual with high susceptibility to a disease without adequate time for active immunization Antibody rejection may alleviate or suppress effects of antigenic toxin |
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describe active immunity
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Active Immunity
A protected state owing to the body’s immune response as a result of active infection or immunization |
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defensins
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Defensins are a family of small cationic, antibiotic peptides that contain six cysteines in disulfide linkage. The peptides are abundant in phagocytes and small intestinal mucosa of humans and other mammals and in the hemolymph of insects. They contribute to host defense against microbes and may participate in tissue inflammation and endocrine regulation during infection. Iinnate
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selectins
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During an inflammatory response, stimuli such as histamine and thrombin cause endothelial cells to mobilize P-selectin from stores inside the cell to the cell surface. In addition, cytokines such as TNF-alpha stimulate the expression of E-selectin and additional P-selectin a few hours later.
As the leukocyte rolls along the blood vessel wall, the distal lectin-like domain of the selectin binds to certain carbohydrate groups presented on proteins (such as PSGL-1) on the leukocyte, which slows the cell and allows it to leave the blood vessel and enter the site of infection. The low-affinity nature of selectins is what allows the characteristic "rolling" action attributed to leukocytes during the leukocyte adhesion cascade[2]. |
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shift to the left
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an increase in the number of immature leukocytes in the peripheral blood, particularly neutrophil band cells
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kupffer cells
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specialized macrophages located in the liver lining the walls of the sinusoids that form part of the reticuloendothelial system (RES) (aka: mononuclear phagocyte system).
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Langerhans cells
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In skin infections, the local Langerhans cells take up and process microbial antigens to become fully-functional antigen-presenting cells.
Generally, dendritic cells in tissue are active in the capture, uptake and processing of antigens. Once dendritic cells arrive in secondary lymphoid tissue, however, they lose these properties while gaining the capacity to interact with naive T-cells. Langerhans cells derive from the cellular differentiation of monocytes with the marker "Gr-1" (also known as "Ly-6G/Ly-6C"). This differentiation requires stimulation by colony stimulating factor (CSF)-1.[6] They are similar in morphology and function to macrophages. |
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dendritic cells
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Their main function is to process antigen material and present it on the surface to other cells of the immune system. That is, they function as antigen-presenting cells. They act as messengers between the innate and adaptive immunity.
Dendritic cells are present in tissues in contact with the external environment, such as the skin (where there is a specialized dendritic cell type called Langerhans cells) and the inner lining of the nose, lungs, stomach and intestines. They can also be found in an immature state in the blood. Once activated, they migrate to the lymph nodes where they interact with T cells and B cells to initiate and shape the adaptive immune response. |
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neutrophilia
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increase in number of circulating neutrophils
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arachidonic acid
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Arachidonic acid does still play a central role in inflammation related to injury and many diseased states
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WHAT ARE THE 5 PARTS OF AN SF-364 (G/S/D/R/C)?
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- GENERAL INFORMATION
- SHIPMENT, BILLING, RECEIPT DATA - DISCREPANCY DATA - REMARKS - CLOSING |
1
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What form is used for shipping discrepancies from dod source of supplies?
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SF361
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kinins
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kinins are inflammatory mediators that cause dilation of blood vessels and increased vascular permeability. Kinins are small peptides They act on phospholipase and increase arachidonic acid release and thus prostaglandin (PGE2) production
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diapedesis
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The movement or passage of blood cells, especially white blood cells, through intact capillary walls into surrounding body tissue. Also called migration
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diapedesis
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the movement of leukocytes out of the circulatory system, towards the site of tissue damage or infection. This process forms part of the innate immune response, involving the recruitment of non-specific leukocytes. Monocytes also use this process in the absence of infection or tissue damage during their development into macrophages.
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what are the three steps to acute inflammation
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Acute inflammation has three major components:
* Alteration in vessels leading to increased blood flow to the area. *Structural changes in microvessels that allow plasma protein and WBCs to leave the circulation. Capillaries are composed; endothelial cells and fluid leaves the capillary at the junction between the endothelial cells. Inflammatory stimulus causes these junctions to open up widder than normally which allows excess fluid to get out of vessel. After fluid leaves vessel the blood get thicker because of large protein particles and cells which stay inside vessel. This is referred to as stasis because the blood flow slows down. Now the white blood cells start to line up along the peripheral edges of the vessel. This is called margination or pavementing. *Emigration of WBCs from vessels so they can accumulate at the site of injury. |
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what are the four theories of autoimmunity?
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Antigenic mimicry theory
Self/foreign antigens made of same materials, so small alterations in self tissue lead to attack 2. Release of sequestered antigens Self antigens not in direct contact with lymphocytes during fetal Autoimmunity Theories development Antigens “hid” in places lymphatics couldn’t reach. When illness hits, Ag’s released 3. T‐cell theories Thymus gland defects Decreased suppressor T‐cell function Altered T helper cell function 4. B‐cell theories B cells lose their responsiveness to suppressor T‐cell signals: ↑↑in B cell function and autoAb production |
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DiGeorge Syndrome
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thymic hypoplasia
total loss of thymus t cell development decrease |
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what is the most important mediator of Type I hypersensitivity reactions
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histamines
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what is the hallmark of hiv and aids
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defective cell mediated immunity: decrease in CD4 /t helper lymphocytes
HIV targets the conductor of our immune system |
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what does glycoprotein 120 (GP120) do in the etiology of HIV
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Gp120 is important:
Allows the virus to Attach to CD4+ (Th) Cells with help of Chemokine receptors CXCR4 and CCR5 |
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what is the HIV structure
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Viral envelope
Consists of membrane derived from host cell Viral glycoprotein studs protrude from cell Etiology membrane Contains proteins gp120and pg 41 |
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how does the HIV get into the lymph node to kill T cells?
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HIV adheres to the dendritic cell, the DC engulfs it, carries it to the lymph node, so the virus uses the DC as a “Trojan Horse” to sneak
into lymph node |
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once HIV is in the lymph node, what happens
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Virus binds by gp120 envelope to the CD4
molecule on Th cell ‐gp120 has high affinity for Th cells 3. Binding to the Th cell via gp120 allows binding to co‐receptors CCR5 and CXCR4 ‐binding of the co‐receptors causes the Th cell membrane to melt away, virus + cell fuse |
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what happens after the t cell membrane melts away?
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Virus injects core into cell, activates
reverse transcriptase and copying begins ‐RNADNAprotein ‐virus’s DNA is now incorporated into the host Th HIV Binding and Infection, cont. cell’s DNA ‐all new copies of cells now infected 5. Virus buds from infected cell, tearing holes in the membranes 6. As new copies made, gp120 protein is replicated and allows fusion to more Th cells |
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what happens when the t helper cells fuse with the virus?
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When Th cells fuse, a huge SYNCYTIUM forms
7. ‐syncytium is a multinucleated mass of cytoplasm created by fusion of many cells 8. ‐this is how virus infects multiple Th cells at once 8. Syncytium prevents receptor availability for HIV Binding and Infection, cont Ab binding ‐Antibodies are useless |
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what is a poor prognostic sign for HIV
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an accelerating fall in the CD4/CD8 ratio is poor
prognostic sign |
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why does b cell responsiveness decrease with HI'v?
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as t cell numbers decline, B cell responsiveness decreases because of
dependence on T‐cell helper cytokines |
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