Inflammation Flashcards
What causes heat and what are its benefits during infection?
The pyrogens Il-6 and IL-1B. They increase the metabolism of immune cells and decrease microbial growth.
PGE2 also acts on neurones to increase body temperature.
What causes redness and swelling? Benefits?
Extravasation from capillaries and post capillaires causes swelling, and increases leukoctye infiltration as well as infiltration of collections, pentraxins, complement, natural antibodies and ficolins.
Pain?
Caused by nociceptive stimuli, e.g. bradykinin and alarmins.
How might inflammation contribute to loss of function?
increased infiltration of lymphocytes, smooth muscel contractin and over secretino of mucus. Inflammation break down of tight junctions (MCLK?0)
What 3 detrimental effects can inflammation lead to if not resolved?
Autoimmune disease and inflammatory tissue damage, sepsis.
Lack of tissue repair can cause fibrosis.
Adaption to stress- shift in homoestatic balance, Autoinflammatory disease.
What causes acute inflammatory responses? And what cells contribute?
Pathogens and tissue damage.
innate cells essentially, especially neutrophils NK cells, monocytes and other granuloctyes.
Maybe other innate like cells?
Primary mecahnisms of actue infections?
vasoactive amines and eicosanoids.
Why might eicosanoids take longer to react?
Synthesised through the arachindonic pathway.
Examples of eicosanoids?
PGE2 and leukotrienes.
Functions of PGE2? And Luekotrienes?
Increase vasodilation and acts on neurones to act as a pyrogen. Very chemotactic for Th2 and eosinophils for the lungs.
Leukoctrienes also cause vasodilation and recruit neturophils.
How does C3a and C5a contribute to acute inflammation?
C3a and C5a can bind to mast cells and stimulate histamine release- vasodilation and extravastion.
They can both also act as chemoattractant e.g, forneutrophils and macrophages.
plsamin in actue inflammation?
breaks down fibrin clots, and cleaves complemet C3.
Also activates Factor XII.
What can factor XII do?
Factor XII can stimulate coagulation and fibrinolysis.
More importantly, factor XII activates the kinin system.
what can bradykinin do?
pain, vasodilation and permeability and causes smooth muscle contraction.
Can PGE2 cause phenotypic changes to immune cells?
Yes, can act on DCs to increase their IL-23production, to favour Th17 cell differentiation.