acute inflammation Flashcards
phases of acute inflammation
vascular phase
cellular phase
what happens in the vascular phase of acute inflammation
changes to maximise movement of bloo proteins and leukocytes out of circulation and into site of infection and injury
main changes are vasodilation and increased vascular permeability
mechanisms of increased vascular permeability
a) retraction of endothelial cells
b) direct endothelial injury
steps of leukocyte recruitment to site of injury
margination
rolling and adhesion
migration
margination definition
movement of leukocytes to a peripheral position along the endothelial surface
what happens during rolling and adhesion
leukocytes intitally roll along the endothelial surface and becom firmly adhered to the endothelium prior to migrting across the vessel wall
chemotaxis definition
directed migration of a cell in response to a chemical stimulus
migration of leukocytes
is when leukocytes migrate through the endothelium
what two processes facilitate recognition and destruction of offending agents in cellular phase of acute inflammation
opsonization and phagocytosis
opsonization definition
process that helps the immune system identify and destroy damaged cells or pathogens
process of opsonization
opsonins coat cells or pathogens so cells of immune system can recognise them
cells known as professional phagocytes
neutrophils and macrophages
characteristics of exudates
high protein and cell concentration and high specific gravity
characteristics of transudates
fluid with low to moderate protein control and few cells
common cause of exudates
an increase in normal permeability of small blood vessels in an araa of injury and therefore an inflammatory response
