Acute inflammation Flashcards
3 key features of acute inflammation
- Increased blood flow - vasodilation
- Increased vascular permeability
- Recruitment and activation of leukocytes
3 transudate features of edema
- Low fluid protein
- Low fluid cellularity
- Low specific gravity
–> NO inflammatory process
Exudate features of edema
- High fluid protein
- High cellularity and
- High specific gravity
–> Indicates INFLAMMATION
Vasodilation and stasis of edema and swelling is due to
- Nitric oxide
2. Histamine
4 mechanisms of increasing vascular permeability
- Endothelial retraction
- Direct endothelial injury
- Leukocyte induced endothelial injury
- Transcytosis
Mechanism of endothelial cell retraction and describe onset and duration
- Nitric oxide/histamine
2. Rapid onset and short-lived
Describe onset and duration of direct endothelial cell injury
Rapid
LONG-lived (takes time to re-endothelialize vessels)
- caused by burns/toxins
Describe onset and duration of Leukocyte induced endothelial injury
DELAYED onset
LONG-lived
- late in inflammation
Mechanism of Transcytosis
Interconnected, uncoated vesicles - vesiculovacuolar organelle
Example of disease with a transudate fluid
CHF
renal failure
liver failure (decrease in proteins and decreased oncotic pressure)
Example of disease with exudate fluid
Acute pneumonia
cancer
Order of leukocyte response
- Macrophages secrete IL-1, TNF
- stimulate expression of secretins
- adhesion of neutrophils
- integrins stop the rolling
- Diapedesis
- chemotaxis
What are selectins?
LOW affinity adhesion molecules bind Lewis antigens on leukocytes
Endothelial cells express selectins after secretion of which cytokines
IL-1 and TNFa from macrophages
Integrins are
HIGH affinity adhesion molecules that bind endothelium
Describe Diapedesis
Migration of the leukocyte through endothelium with help of CD31
Chemotaxis
Migration of leukocytes along a chemokine gradient in interstitium
Examples (3) of chemokine gradient proteins
- Bacterial products
- Leukotriene B4
- Complement 5A
After phagocytosis there is the formation of the
phagolysosome
2 methods employed by the lysosome to degrade offending agents
- Digestion by lysosomal enzymes
2. Free radicals/ROS production
3 free radicals in the lysosome
- Phagocyte oxidase - superoxide anion
- Myeloperoxidase - Hypochlorite anion
- Nitric oxide synthase - NOS - peroxynitrie anion- created by inducible NOS
What is Chediak-Higashi syndrome?
Failure of lysosome and phagosome fusion - accumulation of enzymes in dilated lysosomes
What is chronic granulomatous disease?
failure of oxidative burst -
Deficiency in PHAGOCYTE OXIDASE
leads to accumulation of phagocytes (macrophages)
Myeloperoxidase deficiency
Defective halogenation and inefficient bacterial killing
-need chloride anion
Neutrophils are thought of as…. what type of responder?
Early responders
Key features of neutrophils
- Lower phagocytic activity
- HIGH lysosomal enzymes -
secrete into interstitium and leads to injury
Monocytes and macrophages peak
2 days after edema
Key features of macrophages
LOWer quantity of enzymes
HIGHER phagocytic activity
– remove debris and wound repair
IFN-gamma induces what type of macrophage?
M1 - microbicidal - pathologic inflammation
which 2 cytokines promote a M2 macrophage response - wound repair and fibrosis?
IL-13 and IL-4
The mediators of inflammation are
activated by a variety of stimuli
SHORT-lived -
Extensive crosstalk
The mediators of inflammation are present in what form
Inactive precursor enzymes
4 cardinal features of acute inflammation
redness, swelling, heat, pain, and LOSS OF FUNCTION
what is acute lymphangitis
When inflammation which is normally found in venules and capillaries now tracks along lymphatic system
