Lecture one Flashcards
(29 cards)
Name anatomic barriers of the immune system
skin, oral mucosa, respiratory epithelium, intestine
name complement proteins and antimicrobial proteins
C3, defensins, RegIIIgamma
give examples of innate immune cells
macrophages, granulocytes, natural killer cells
give examples of cells of the adaptive immune system?
T cells and B cells
Give the four phases of the immune response
inflammatory inducers (ie: LPS, urate crystals, ATP) sensor cells (PRRs on macrophages, dendritic cells, neutrophils), mediators (chemokines and cytokines), target tissues (produce antimicrobial proteins, induce intracellular antiviral proteins, kill infected cells)
describe the innate immune response briefly
inflammation, complement activation, phagocytosis and destruction of pathogen
give two broad locations of pathogens
intracellular or extracellular
how do we protect ourselves against pathogens who’s site of infection is extracellular, in the blood, lymph, interstitial spaces?
via complement activation, phagocytosis, and production of antibodies
how do we protect ourselves against pathogens who’s site of infection is extracellular, in the epithelial surfaces?
via antimicrobial peptides, antibodies, specifically IgA
How are we protected against pathogens who’s site of infection is in the cytoplasm?
NK cells, cytotoxic T cells (viral/foreign component detected in the cell via NOD receptors or RIG-I or degraded in normal proteasomal recycling, displayed on MHC I)
how do we protect ourselves from pathogens who’s site of infection is intracellular in the vesicles?
T cell and NK cell dependent macrophage activation
give an example of a pathogen that produces a exotoxin
staphylococcus aureus
give an example of a pathogen that produces an endotoxin
E. Coli
what effect do chemokines and cytokines released by macrophages when they phagocytose a pathogen have on the site of infcetion?
vasodilation, increased vascular permeability, redness, heat, swelling
what do mast cells do
produce histamine, produce chemotactic factors and cytokines
which immune cells protect against parasites
eosinophils and basophils
describe the microbicidal mechanisms of phagocytes?
the PAMP triggering the phagocyte binds to the GPCR (PRR), GTP binds, turns on and activates enzymes like phosphoinositol-3 kinase that is involved in cytoskeletal reoorganisation in response to chemokines, activates PLC-gamma-2 leading to lysosomal degranulation and phosphorylation of p47phox via activation of PKC, MEK and MAP Kinase systems that oversee the assembly of the NADPH oxidase
describe the process of neutrophil NET formation
can occur within 1-2 hrs of neutrophil activation, involves liberation of neutrophil DNA, histones, and granule enxymes into the extracellular space where they can ensnare bacteria, yeast, and other pathogens and killl them in situ
name receptors on the surface of macrophages
mannose receptor, Glucan receptor, TLR1:TLR2 heterodimer, scavenger receptor
name the chemokines/cytokines secreted by activated macrophages?
TNF, IL-6, IL-8, IL-12
Give the functions of TNF, IL-6, IL-8, IL-12
TNF: activates local endothelium, initiates cytokine production, upregulates adhesion molecules
IL-6: triggers production of acute phase proteins in the liver, enhances Ab production by B cells, induces T cell polarisation
IL-12: activation of NK cells; polarisation of T cells to Th cells
what is the effector function of NK cells
release lytic granules that kill some virus-infceted cells, results in apoptosis
define PAMPs
Pathogen Associated Molecular Patterns that the immune system recognises as foreign.
PRRs can be _ or _
soluble or cell associated
