Acute and Chronic Inflammation and Hypersensitivity Flashcards
What are the 5 signs of inflammation?
calor (heat) rubor (redness) tumor (swelling) dolor (pain) functio lasea (loss of function)
What are the features of acute inflammation?
fast
mainly neutrophil infiltrates
usually mild and self-limited tissue injury and fibrosis
local and systemic signs are prominent
What are the features of chronic inflammation?
onset is slow
cellular infiltrates monocytes/macrophages and lymphocytes
tissue injury and fibrosis are often sever and progressive
local and systemic sign are less prominent; maybe subtle
What are the stimuli for acute inflammation?
infecitons and microbial toxins physical trauma physical and chemical agents tissue necrosis foreign bodies immune reactions
What are the abnormal stimulus recognized by for initation of inflammation?
epithelial cells (skin, linings of GI and resp tract) dendritic cells (epithelia and most organs) phagocytes (connective tissue and organ)
Receptor recognize molecular tructure on microbes by what?
toll like receptor: located in plasma membrane
inflammasome: cytoplasmic complex recognizing part of dead cells
trigger activation of casapse-1 which activates IL-1
Key difference between TLR and inflammasome is what?
TLR recognize extracellular microbes and Patterns associated with external things
Inflammasome recognizes products of dead cells and some microbes.
What mediators cause pain and vasodilation in inflammation?
increase permeablility and pain
What are the role of selectins?
Seen on endothelial cells, platelets, leukocytes
P-selectin, L-selectin, etc.
aid in rolling and loose attachment to endothelial cells
What are the role of integrins in inflammation?
expression of chemokines on endothelial cells activate integrins
TNF adn IL-1 secreted by macrophages at the site of injury increase endothelial cell ligan expression
result in more stable attachment of leukocytes
What endothelial cell marker causes transmigration?
PECAM1 (CD31)
What are the chemotactic factors that cause cells to migrate to injury site?
bacterial products
chemokines
complement (3a and 5a)
leukotrienes
What are opsonins?
include IgG complement protein and lectins
-coat microbes and increase rate of phagocytosis
What are the 2 ways in which phagocytosed things are degraded?
ROS (reactive oxygen species) dependent mechanisms
and enzyme destruction either from elastase, or lysozymes
What are the vasodilators involved in inflammation?
histamine (mast cell, basophils, platelets) , nitric oxide (endotehlium, macrophages) and prostaglandins (mast cells, leukoctyes)
What are the principle mediators that increase vascular permeability?
Histamine, serotonin (mast cells, basophils, platelets)
C3a, C5a
Bradykinin
leukotrienes C4, D4, E4 (mast cells, leukocytes)
platelet activating factor (mast cells, leukocytes)
Substance P (leukocytes, axons)
What are the principles mediators of chemotaxis, leukocytes recruitment and activation?
IL-1, TNF (macrophages, endothelial cell, mast cells)
Chemokines (leukocytes, activated macrophages)
C3a, C5a
Leukotriene B4 (Mast cells, leukocytes)
Bacterial products
What are the principle mediators of Fever?
IL-1 and TNFalpha (macrophages, endothelial cells, mast cells)
What are the mediators of tissue damage in inflammation?
lysosomal enzymes of leukocytes (leukocytes)
ROS (leukocytes)
Nitric oxide (endothelium, macrophages)
What are the outcomes of acute inflammation?
1 termination of acute and inflammatory response
-meditors degrade, leukoctyes die, debris cleared by macrophages
2. progression to chronic inflammation
3 scarring or fibrosis
What are the morphologic patterns of acute inflammation (4)?
- serous
- fibrinous
- suppurative
- ulcer
What are the serous inflammation signs?
mildest form of acute inflammation
outpuring of thing fluid from plasma or serosal cavity
ie peritoneal, pleural, pericardial, skin blister, viral infection
What are the signs of fibrinous inflammation?
occurs secondary to more severe injury
larger vascular leaks, passage of fibrinogen, conversion to fibrin
affects linings
may resolve completely or may organize leading to scarring
What are the signs of suppurative (purulent) inflammation?
when large number of neutrophils present along with necrotic cells, eema fluid and bacteria = PUS
What is an abscess?
central area of necrotic tissue surrounded by preserved neutrophils, dilated vessels, and fibroblastic proliferation
What is an ulcer?
local defect, surface of organ or tissue
sloughing of surface covering and necrotic inflammatory tissue
What are the signs of chornic inflammation?
leukocytes present, inflammation of prolonged duration
active inflammation, injury and healing occuring at teh same itme
What are causes of chronic inflammation?
persistent infection that are difficult to eradicate
prolonged exposure to toxic agents
immune-mediated inflammatory diseases( autoimmune)
What do macrophages do in chronic ifnlammation?
they persist, secrete products that result in continued tissue injury, IFNgamma one of persistance
What cells are involved in chronic inflammation?
Adaptive immune response is activated Lymphocytes Plasma cells Immunoglobulins Eosiophils in parasitic inflammation Mast Cells: found in connective tissue