BIOL: intrinsic and innate immunity Flashcards
classic inflammation response (latin version)
calor, tumor, rubor, and dolar
calor
refers to heat
tumor
refers to swelling
rubor
refers to redness
dolar
refers to pain and loss of function
acronym for inflammation symptoms
PRISH; pain, redness, immobility, swelling, and heat
adjuvants
inflammatory molecules that are added to vaccines are help non-infectious agents replicate and initiate a host immune response
inflammation
is a nonspecific response to tissue damage and is part of the innate response of the immune system to help heal and attack the injectious agent
how might tissue damage occur?
excess heat or cold, chemical damage, UV damage, cuts, pathogens, etc .
acute inflammation
develops quickly and is beneficial because it eliminates causes; is usually quite localized
chronic inflammation
is long-lasting, damages tissues, and causes diseases; is a result of the immune system overreacting
ex. of a chronic inflammation
rheumatoid arthritis or Crohn’s disease
what is the first response in inflammation?
vasodilation and increased blood vessel permeability
what is the result of vasodilation and increased permeability?
allows for cells to migrate from the bloodstream into the ISF; this is what causes redness and temperature in the inflammatory response
what does blood clotting trigger the release of?
this initial source of injury activates bradykinin and histamine, and these are mediators that cause vasodilation
what causes vasodilation of the vessels?
histamine and bradykinins
what causes increased permeability of the blood vessels?
prostaglandins and leukotrienes which are activated by the wound
diapedesis
the process of WBCs migrating from the blood circulation to specific sites of injury due to increased permeability of the vessels
how long does it take for phagocytosis to begin after inflammation?
1 hour
what are neutrophils attracted to?
kinins, prostaglandins, and complement
what are prostaglandins released from?
damaged cells
what is a fever?
an abnormally high body temperature caused by the reset of the hypothalamic thermostat
why does the heat of a fever do?
intensifies the effect of inferons, inhibits the growth of microorganisms, and speeds up the body reactions that aid in repair
another name for blood clotting
hemostasis
3 stages in hemostasis
vascular spasm, platelet plug formation, and blood coagulation
vascular spasm
first stage of hemostasis; vessels constrict to limit blood flow to the area (tunica media smooth muscle), inhibiting blood loss
three steps of the platelet plug formation
platelet adhesion, platelet release reaction, and platelet aggregation
platelet adhesion
the exposed collagen in the break of the vessel attracts platelets to the endothelium
platelet release reaction
changes the shape and appearance of platelets, allowing them to attach to each other around the wound, while also releasing their products from their vesicles
what materials do platelets release?
liberated ADP, thromboxane A2, and serotonin
what released platelet factors activate nearby platelets?
ADP and thromboxane A2
what released platelet factors maintain contraction of the vessels?
serotonin and thromboxane A2
platelet aggregation
as a result of activated platelets that release chemicals, a platelet plug is formed to block the wound (a group of many platelets that form a ‘plug’)
fibrin
is activated to make blood clots after the platelet plug is formed
what clotting factors begins the blood clot formation?
tissue factor which is part of the extrinsic pathway
what ion is essential for blood clot formation
calcium
what does the extrinsic pathway activate?
factor X
what is the result of factor X?
prothrombinase (an enzyme), which converts prothrombin to thrombin
what is thrombin?
converts fibrinogen to fibrin
fibrinogen
converted to fibrin by thrombin; it is an inactive protein that circulates in the blood
intrinsic pathway
can be activated by thrombin and this is a positive feedback mechanism that triggers more production of prothrombinase to eventually produce more fibrin
three jobs of thrombin
convert fibrinogen to fibrin, reinforce the strength of the threads, and via a positive feedback mechanism triggers the production of prothrombinase via the intrinsic pathway
how many clotting factors are there?
12
clot retraction
is the tightening of the fibrin clot; as it tightens, the edges of the wound are brought closer together and fibroblasts can start doing their job
role of fibroblasts in clot formation
they make underlying CT to repair the gap in the vessel
vitamin K significance
vitamin K is significant for being a precursor for a numerous amount of clotting factors (4/12)
how is vitamin K created?
as a waste product of E coli in the large intestine
vitamin K deficiency
can be dangerous for abnormal blood clotting
why can blood clotting be dangerous?
it can create blood clots that can create obstructions
fibrinolytic system
is a complicated pathway that interacts with the clotting pathway; plasminogen is converted to plasmin, which inactivates fibrin to dissolve the clot
plasminogen
is an inactive enzyme that gets incorporated into the clot; is later converted to plasmin
plasmin
created from plasminogen and inactives fibrin to dissolve the clot
what converts plasminogen to plasmin
chemicals in the blood and healthy body tissues
two anti-blood clotting drugs
heparin and warfarin (coumarin)
heparin
is given via injection to prevent or delay blood clots from forming via blocking clotting factors
what does heparin interact with in the blood
antithrombin III, enhancing its ability to inhibit blood clotting factors
APTT
activated partial thromboplastin time; this isolates blood plasma and adds calcium and some downstream effect like a phospholipid, then the intrinsic pathway is activated and clotting time is measured
warfarin
this blocks the reactions in the liver to make vitamin K, thus inhibiting the formation of clotting factors (specifically it inhibits 4); longer effects
prothrombin time
measures the extrinsic pathway by adding tissue factor, then calcium, which then activates the intrinsic pathway
APPT and PT
PT < APTT
intrinsic immunity
is the non-specific first line of defence that is the skin and the mucus membrane
what is part of the skin and mucus membranes?
epidermis (sweat, sebum, dead cells), mucus membranes (cilia and mucus), lacrimal apparatus (lysozyme), saliva (contains antibacterial chemicals), urine (flow cleanses the urethra), defecation/vomiting, and gastric juice (low pH)
lysozyme
an enzyme that targets bacterial cell walls to create osmotic forces and is found in tears to protect the conjunctiva
innate immunity
second line of defence that is non-specific and include interferons, the complement system, and phagocytosis
complement system
a defence system that consists of over 30 proteins that are constantly circulating in the bloodstream waiting to be activated
3 results of activated complement system
phagocytosis, inflammation responses, and cytolysis
cytolysis
a combination of proteins insert themselves into the membrane of a microorganisms, breaking down concentration gradients which cause them to die
3 complement activating pathways
classical, alternative, and lectin
classical pathway
occurs when an antigen binds to an antibody triggering the complement pathway
alternative pathway
activates the complement system by microbe specific lipid carbohydrate complexes on the surface of microorganisms that are specific to them
lectin pathway
is produced when a macrophage releases certain chemicals after they have phagocytosed a new invade; this produces lectin which activates the liver to produce lectin, activating complement
iron binding proteins
iron need bacteria to live so free circulating iron in the body needs to be protected
key iron proteins
transferrin, ferritin, lactoferrin, hemoglobin, and myoglobin
where is transferrin found?
plasma and ISF
where is ferritin found?
the liver
where is lactoferrin found?
milk, saliva, and mucus
where is hemoglobin found?
RBCs
where is myoglobin found?
muscle cells
4 antimicrobial proteins
dermcidin, defensins, cathelicidins, and thrombocid
dermcidin
produced in sweat glands and function to create osmotic forces to kill bacteria
defensins
are naturally released by macrophages, neutrophils, and epithelia
cathelicidins
are released by macrophages, neutrophils, and epithelia
thromdocidin
released by platelets
what are functions of antimicrobial proteins?
they kill the microorganism in question and attract dendritic cells (phagocytes) and mast cells (histamine) to the scene
natural killer cell
is a lymphocyte that kill foreign material by directly attaching to to its receptors and releasing destructive proteins
where are natural killer cells found?
the spleen, red bone marrow, lymph nodes, and blood
destructive proteins released by natural killer cells
perforin and granzyme
perforin
released by natural killer cells and put a hole in the membrane, creating osmotic forces
granzyme
released by natural killer cells and make the target cell undergo apoptosis
apoptosis
programmed cell death
what are the first responders to an injury site or infection?
neutrophils and macrophages (large phagocytes)
2 types of macrophages
fixed or wandering
wandering macrophages
actively undergoing phagocytosis
fixed macrophages
defensive cells for important tissues; ex. kupfer cells or microglial cells
first stage of phagocytosis
chemotaxis
what does hemostasis prevent?
hemorrhages
where are complement proteins created?
in the liver
how is phagocytosis complement activated?
the complement system tags proteins onto the microorganism, making them attracted to a phagocytic cell
opsonization
the addition of proteins to a microorganism to enhance the phagocytosis process
most commonly used antimicrobial proteins
decisions and defensins
why does redness occur for inflammation?
vasodilation
what causes heat for inflammation?
vasodilation
why does swelling occur in inflammation?
excess ISF due to increased permeability of the vessel
why does pain occur in inflammation?
increased ISF puts pressure on nerves
extrinsic pathway
damage to a vessel releases tissue factor and this is spreads into the bloodstream, and through a series of steps, activates factor X, resulting in prothrombinase
extrinsic/intrinsic activation times
extrinsic occurs fast but doesn’t last long, whereas intrinsic takes longer to occur but has permanent effects
another name for warfarin
coumarin
components of the innate system
antimicrobial proteins, macrophages, complement proteins, interferons, iron binding proteins, and natural killer cells
what does plasmin inactivate?
prothrombin and fibrinogen
heparin vs coumarin
coumarin takes longer for results but is more long lasting than heparin; coumarin also is taken orally, whereas heparin is given via injection
