Inflammation 2 Flashcards
What are the events of acute inflammation
Stimulus for inflammation
Vascular changes
Cellular events
Termination of acute inflammatory response
What can be the cause of acute inflammation
Infectious agents
Trauma
Necrotic tissue
Immune reactions
What are the inflammatory mediators of acute inflammation
Vasoactive amines Plasma proteases: complement Lipid mediators Platelet activating factor Cytokines Chemokines Nitric Oxide
What are the vascular changes in acute inflammation
Increased vascular flow (hyperemia) and blood vessels
Increased vascular permeability (capillaries and post-capillaries)
What are the cellular events of acute inflmmation
Extravasation- deliver of WBC to site of injury
Migration- cytokines
Rolling- selectin/integrin
Activation and Adhesion- integrin and chemokines
Transmigration - P-CAM
The process where WBC emigrate in tissues towards the site of injury
Chemotaxis
What are the 3 processes involved in phagocytosis
Recognition and attachment of particle
Engulfment with subsequent formation of phagocytic vacuole
Killing or degradation on ingested material
How is the acute inflammatory response terminated
Degrade inflammatory mediators
Stop signals
->pro-inflammatory leukotrienes to anti-inflammatory lipoxins from arachidonic acid
-> anti-inflammatory cytokines from macrophages
-> neural impulse inhibits TNF production in macrophages
What are the four outcomes of acute inflammation
Complete resolution
Healing by scarring
Abscess formation
Chronic inflammation
What is involved in inflammatory resolution
Neutralization of chemical mediators
Return to normal vascular permeability
Stop lymphocytic infiltration and removal of edema
Healing by scarring often occurs in what type of tissue
Tissues that do not have the ability to regenerate
How can chronic inflammation arise?
Following acute inflammation - persistent stimulus or interference in normal process
Repeated bouts of acute inflammation
Low grade response
Persistent infection by intracellular micro organisms which are low toxicity or prolonged exposure to non-degradable substances usually result in what kind of inflammation
Chronic
A small organized collection of modified macrophages (epithelioid cells) surrounded by a rim of lymphocytes
Granuloma
Granulomatous inflammation = Chronic!
What are some causes of granulomatous inflammation
Insert particles. Eg silica/asbestos Lipid resistant to metabolism Bacterial resistant to lysosomal degradation Systemic fungal agents Foreign bodies
What are the cells involved in granulomatous inflmmation
Epithelioid cells
Multinucleated giant cells
Lymphocytes
A large, pale-staining, eosinophilic macrophage with a ovoid nucleus, rich with ER, golgi, and vesicles
Epithelioid cells
Fusion of macrophages induced by cytokines causes formation of ______________________
Multinucleated giant cells
Nuclei are sometimes arranged around the periphery
What are the roles of T lymphocytes
To produce lymphokine and interferons
To attract ad activate macrophages
To induce formation of multinucleated giant cells
What are the two patterns of chronic inflammation?
Diffuse thickening of affected tissue (eg Johnes disease)
Solid, firm, nodular lesions ->may compress adjacent tissue