Granulation Tissue - Acute Inflammation To Fibrosis Flashcards
What are the most prevelent cells during the first 24H of inflammation?
Neutrophils
At which stage do we see macrophages in the inflammed tissue?
48-96H after onset
What ae some of the key roles that macrophages play (inflammation to fibrosis)
They begin cellular repair,
Clear extracellular debris, fibrin and foreign material
Promote the deposition of new ECM and angiogenesis
What drives the migration of fibroblasts to the site of injury?
Chemokines and TNF and TGF-beta
All produced mainly by macrophages
What drives fibroblast proliferation
IL1 and TNF
Produced by macrophages
What is granulation tissue?
Pink, soft, vascularised, granular appearing tissue at the site of inflammation
What forms granulation tissue?
The proliferation of fibroblasts and vascular endothelial cells in the first 24H of the repair process
What is fibrosis? When does it occur?
Fibrosis is the excessive deposition of collagen and other ECM components in a tissue.
It occurs when the granulation process is too extensive
Why is fibrosis dangerous?
It usually causes serious organ disfunction and ultimately organ failure
What is TGF-Beta? Describe it’s role
A fibrogenic agent (potently stimulates fibroblast proliferation and migration) which causes increased collagen and fibronectin synthesis AND decreased degradation of ECM.
Produced by macrophages and most cells in granulation tissue
