Lect 2 - Inflammation Flashcards
What is inflammation
Inflammation is the response of the of innate immune system to invading pathogen. It involves a series of physiological and cellular changes at the site of invasion.
Define and differentiate the two types of inflammation
Acute: the initial response of the body, characterised by increased movement (exudate) of plasma proteins and leukocytes (neutrophils). the timing of acute inflammation is short.
Chronic: the prolonged time course changes the types of cells that are exudated. there is a shift that is characterised by the simultaneous destruction and healing of tissue (fibrosis, tissue necrosis). cells in chronic inflammation include macrophages, more lymphocytes.
Describe what happens during the inflammation process
microvasculature: initial vasoconstriction to stop blood loss, this is followed by vasodilation caused by exudation of plasma, plasma proteins, erythrocytes (chemotaxis), and leukocytes.
there is a slow in blood flow caused by margination of platelets and leukocytes.
cells: cells involved in inflammation originated from either plasma or tissue.
in the tissue, mast cells release inflammatory mediators whose main role is to attract more leukocytes to the site of injury. there will also be macrophages which releases signal cytokines and phagocytose foreign bodies.
in the plasma, granulocytes such as neutrophils (engulf and kill), eosinophil (peroxide), basophil (heparin, and platelets (prostaglandin).
inflammatory mediators: these are products of cells, tissue, and proteins. the function of these mediators is to attract more leukocytes to the site (although there are some that inhibit inflammation). these mediators come from 2 sources, plasma and cell tissue.
plasma includes the complement system (phagocytose and opsonin), coagulation-fibrinolytic, and kinin.
tissue derived include cytokine (IL1, IL10) and histamine (biogenic amine).
what are some systemic sequelae of inflammation
raise in temperature - helps opsonization
increase in blood leukocytes
pain (substance P)
swelling (exudate)
plasma protein (C-reactive protein)
vasodilation etc
how is the cascade of complement and coagulation controlled?
there is a series of enzymes that facilitate each step, the sequential process is controlled by enzyme feedback and sequential activation and deactivation of the previous step.
