Acute/chronic inflammation Flashcards
What type of immunity gives rise to acute inflammation
Innate
What type of immunity gives rise to chronic inflammation
Adaptive
Why can scar tissue form?
Following injury if the cell type damaged cannot be replaced, it is substituted for fibroblastic/glial scar tissure
What are the four signs of inflammation?
Heat, swelling, redness, pain
Describe acute inflammation
Mediated by innate immunity
Rapid onset and resolution therefore short lived
What are the vascular changes associated with acute inflammation?
Transient vasoconstriction of arterioles; then vasodilation leading to increased blood flow. Then slowed circulation due to increased permeability of microvasculature.
What is acute serous inflammation?
Inflammation in which accumulation of fluid is dominant feature.
What is exudate?
Inflammatory extravascular fluid with high protein conc ++ high specific gravity
Describe the makeup of pus
Exudate + lots of leucocytes (mostly neutrophils) and parenchymal cell debris
What are Weibel-Palade bodies?
Found within the endothelial cells, they store P selectin and express it on the surface of cells.
What is margination?
Increased adhesion of inflammatory cells to endothelium and rolling along endothelium.
What does P-selectin do on the surface of endothelial cells in inflammation?
It works with E selectin; causes neutrophils to slow down by interacting with carbohydrate receptors and makes them roll along the endothelium.
What does IL-8 do?
Attracts neutrophils along a conc gradient of the chemokine?
What is chemotaxis?
Unidirectional migration of cells towards a chemokine
What are the main inducers of chemotactic agents for neutrophils
Bacterial products
Components of the complement system, particularly activated C5 (C5a)
What can promote diapedesis and extravasation in an immune response?
Interaction between integrin molecules on leukocytes and endothelial adhesion molecules such as ICAM-1 to make a firm connection promoting diapedesis and extravasation
What is acute suppurative inflammation?
Inflammation with visible pus
Describe chronic inflammation
Relatively long duration. Assoc with lymphocytes and macrophages (adaptive immunity)
May follow acute inflammation or may begin as a low grade smouldering response (i.e to persistent infection or to exposure to nondegradable substances like asbestos)
Describe the histology of chronic inflammation
Infiltration by mononuclear cells (like macrophages, lymphocytes and plasma cells)
Proliferation of fibroblasts (leads to fibrosis)
What is the difference between a macrophage and a monocyte?
A macrophage is in the tissue and in the blood it is a monocyte.
