Acute inflammation: cardinal features, events and DAMPs/PAMPs/MAMPs, systemic effects, outcomes Flashcards
What are the 5 cardinal features of acute inflammation?
Rubor: Redness
Dolor: Pain/tenderness
Calor: Heat
Tumour: Swelling
Functio Laesa: Loss of function
What are DAMPs?
Damage-Associated Molecular Patterns are signals released by cells that die by necrosis, that trigger acute inflammation
Give 3 examples of DAMPs that are produced by a damaged mitochondria?
DNA
DNA breakdown byproducts eg. Uric acid, ATP
What are PAMPs/MAMPs?
Pathogen/Microbe-Associated Molecular Patterns are signals produced by pathogens that trigger acute inflammation
Why is acute inflammation necessary when the trigger is outside body tissues?
Acute inflammation response causes blood vessels to become more porous, which allows immune cells to go outside tissues and target the trigger
What are the 5 Rs of acute inflammation:
Recognition
Recruitment
Removal
Regulation
Resolution
What happens in the recognition phase of acute inflammation?
DAMPs/PAMPs/MAMPs are recognised by toll-like receptors on sentinel cells which are already outside body tissues
What is a sentinel cell?
Immune cell that detects presence of DAMPs/PAMPs/MAMPs
What initiates the recruitment phase of acute inflammation?
Binding of DAMPs/PAMPs/MAMPs to toll-like receptor activates the inflammasome
How does the inflammasome recruit neutrophils and macrophages in acute inflammation?
Inflammasome is a multiprotein complex that induces IL-1 production, a cytokine that attracts neutrophils and macrophages
What occurs in the removal phase of acute inflammation?
Neutrophils and macrophages remove injurious agents by phagocytosis
What is the main immune cell in acute inflammation, and how is this detected?
Neutrophil, which causes a raised neutrophil cell count when there is infection/necrotic death
What occurs in the regulation phase of acute inflammation?
Regulation of inflammatory response by switching cytokines to healing type
What occurs in the resolution phase of acute inflammation?
Homeostasis restored
What are the overall 2 general phases of acute inflammation?
Vascular and cellular phases
What general phase are the 5 Rs of acute inflammation a part of?
Cellular phase
What 3 cytokines meditate the systemic effects of acute inflammation?
TNF, IL-1, IL-6
What molecule stimulates production of cytokines by macrophages in acute inflammation?
Pyrogen
What is a pyrogen?
Fever-inducing substance
Give one example of a pyrogen that arises from bacteria?
Lipopolysaccharide
Which cells do IL-2 and TNF increase COX activity in for acute inflammation?
Perivascular cells of hypothalamus
What does PGE2 increase in acute inflammation?
Temperature set point
What type of protein do cytokines increase output of from liver in acute inflammation?
Acute phase proteins
What is an acute phase protein?
Protein whose blood plasma concentration changes in response to inflammation
What is the difference between positive and negative acute phase proteins?
Positive: conc. increases
Negative conc: decreases
How can elevated CRP levels in blood plasma be used to diagnose a type of infection that has resulted in inflammation?
Elevated CRP occurs in response to severe fungal or bacterial infections
What do cytokines increase production of in bone marrow in acute inflammation?
WBCs
What are 2 negative systemic effects of TNF?
Promotes thrombosis
Accelerates atherosclerosis
What blood sugar condition can TNF and IL-1 cause and why?
They cause insulin resistance, which leads to type 2 diabetes
What 2 cytokines do macrophages produce to decrease inflammation and begin repair?
IL-10, Transforming growth factor beta
what substance is formed when a persistent stimulus causes continuous acute inflammation?
Pus
What is pus, and what cytokine promotes its formation?
Collection of neutrophils that are mainly recruited by IL-8
How is an abscess formed in acute inflammation?
Abscess is pus surrounded by a fibrous capsule, and is formed by macrophages
How do macrophages induce chronic inflammation after continuous acute formation?
They recruit T-helper cells, so activate the adaptive immune system