Inflammation, Inflammatory Response and Fever Flashcards
Inflammation: what are the two functions? What type of cells does it occur in? What is it controlled by?
- eliminates harmful agent.
- Sets stage for healing repair.
- Occurs in necrotic cells/ tissue.
- Controlled by cells and mediators (cytokines) two types: acute and chronic
acute inflammation: what is stimulates it? timeframe of action? process? what predominates?
trigger: harmful stimuli or conditions of infection/injury. time:comes on in min-hrs, lasts hrs-days.
process: exudation of fluid and plasma proteins, emigration of neutrophils.
NEUTROPHILS PREDOMINATE THIS
chronic inflammation: timeframe? process? what predominates?
time:lasts days to years.
process:proliferation of blood vessels, tissue necrosis + fibrosis.
MACROPHAGES, EOSINOPHILS, + MAST CELLS PREDOMINATE
types of inflammatory cells
endothelial (includes basophils, eosinophils, lymphocytes, platelets, neutrophils, monocytes.. aka all from myeloid stem cells).
platelets/thrombocytes,
leukocytes: (granulocytes-neutrophils, eosinophils, basophils, mast cells) + (agranulocytes-monocytes/macrophages)
cells in surrounding tissue (not endothelial)
mast cells, fibroblast, elastin, collagen, macrophage, proteoglycan filaments
endothelial cells: 3 general functions- then expand on each
“skin cells of the blood”
-barrier: to microbes and inflammatory mediators (cytokines)
-regulates…
…leukocyte extravasion via expression of adhesion molecules + receptors.
…immune response via releasing inflammatory mediators. …immune cell prolif. via secretion of hematopoietic colony stimulating factors
-helps repair process, producing GFs that stimulate angiogenesis + matrix formation.
platelets (thrombocytes) - critical for? activated by?
- critical for normal hemostasis (blood flow ) + clotting
- once activated, pLts(platelets) secrete >300 proteins- majority are inflamm. mediators.
- pLts activated by PAF (platelet activating factor)
- activated by injury (external and internal)
Leukocytes (WBCs): function in inflammation (3 stages). types of leukocytes?
MAJOR cell component in inflamm.
- enter tissue then
1. destroy infective organisms
2. removing damaged cells
3. releasing inflammatory mediator cells to control further infl. and healing - Types: granulocytes + agranulocytes
granulocytes include…
neutrophils, eosinophils, basophils, mast cells
neutrophils- function? timing for arrival?immature neutrophils? granules contain?
MOST important granulocytes: compose 60-70% of WBCs
- arrive 1st, w/in 90min of inflammation + engulf pathogens
- last up to 10hrs, need to be replenished quickly, all die in apoptosis 24-48hrs
- bands (“baby” immature neutrophils) are in circulation but in very low amts
- granules: contain enzymes that phagocytize microbes and dead tissue
- O2 dependent metabolic pathways that generate toxic O2 and nitrogen (help phagocitize pathogens as well)
bands
immature “baby” neutrophils; these are in bone marrow but ineffective, only called out of bone marrow when there is a dire need- neutrophils are exhausted (like sepsis)
Eosinophils- timeline for arrival? granules contain? lifespan
compose 2-3% of all WBCs
- arrive 3 hrs after neutrophils
- longer lifespan - present in chronic inflammation
- granules contain a protein highly toxic to worms that are too big to phagocytize.. elevated count of this means parasitic (or allergic rxn)
basophils - function? granules contain?
compose <1% of all WBCs
- in allergic rxns esp. w/ IgE, causing vasodilation (redness, swelling, itching)
- granules release histamine + other vasoactive substances
- these are precursors to mast cells which develop when a basophil leaves the circulation
what are cytokines?
mediators help with cell movement
agranulocytes include?
monocytes/macrophages
monocytes/macrophages: produce? function? timeframe?
compose: 3-8% of WBCs
- are monocytes for about 1 day then macrophage in the tissues.
- produce: vasoactive mediators (prostoglandins, leukotrienes, PAF,inflammatory cytokines + GFs)
- help to: destroy all caustic agents, bacterial killing, signal process of immunity (as opposed to inflammation), resolve inflammatory process and initiate healing
- 24 to get to site of injury but then take over + stay
- important in chronic inflammation
CAMS (cell adhesion molecules): function? 3 types expanded
work to help with recruitment and adherence of WBCs of the endothelial wall
- selectins: transmembrane proteins, found in endothelial cells (leukos and platelets) - help transport innate immune cells to where they are supposed to be.
- integrins: proteins that attach to cytoskeleton of ECM
- immunoglobin super family: cell surface proteins, recognition, binding and adhesion (antibodies and immunoglobulins)
LAD1 and LAD2 - too few or too many?
too few of different types:
LAD1- integrins: leukocytes cant get where where they need to be- typically genetic problems- have recurrent infections
LAD2: selectins: usually in middle eastern people (dont know why)- issue with recurrent infections
too many of either: chronic inflammation (i.e. autoimmune disorders)
what is venous dilation? what does it cause?
increase in blood flow- rubor (redness) and calor (heat)
increased vascular permeability causes…(3 things)
tumor (swelling), dolor (pain) functio laesa (loss of function)
acute inflammatory response:stages
- vascular stage 2. cellular stage
4 vascular stages
- momentary vasoconstriction
- vasodilation of arterioles and venules (warmth and redness) and then dilates capillaries
- increased permeability of capillaries
- extravasion of exudate (protein-rich fluid) into extravascular tissues (lead to swelling and pain)
vascular changes are one of the following…
- immediate transient (minor injury. i.e. papercut)
- immediate sustained (major injury)
- delayed hemodynamic response (occurs 2-12 hours after injury. ie. sunburn)
- rapid swelling/tissue expansion causes pain
microcirculation consists of what?
arterioles, capillaries, venules
cellular phase- 4 phases
all WBCs start working
- marginations:lineup along endothelial wall surface- cytokines released, induce endothelial cells to produce CAMs and release cytokines, chemokines, and ROS. TNF alpha induces priming and aggregation of neutrophils
- transmigration: WBCs squeeze through junctions into vessel wall and into extravascular space
- chemotaxis: WBCs through extraCell space guided by cytokines, cellular debris and complement fragments
- phagocytosis: WBCs- recognition, engulfment, + intracellular killing
analogy: drunks lining up, going to bar, eating everything, wreaking havoc on those they dont know
phagocytosis expanded
- recognition and adherence : microbes can bind to specific receptors on phagocytic cells OR
can be recognized by their coating on compliment or antibodies (opsinization)
(2. engulfment then 3. intracellular killing)
types of inflammatory mediators
both short lived
- plasma-derived
- cell-derived
plasma-derived inflamm. mediators: where are they synthesized? what do they do?
- synthesized in liver
- includes: 1. acute phase proteins, 2. coagulation factors, 3. complement proteins
esentially: they bring more cytokines until the pathogen is killed. gradually decreasing number of CtKs its bringing, then inflammation resolves
interleukins and TNFs (tumor necrosis factors) are ____ kind of proteins
acute phase
mast cells produce —–
platelet cells produce —–
these are both types of cell derived mediators (subgroup: preformed mediators)
mast cells : histamine
platelet: serotonin
both important in inflammatory response