7.1.2 Chronic Inflammation Flashcards
What are the 5 principle cells involved in chronic inflammation?
- Lymphocyes
- Plasma cells
- Macrophages
- Fibroblasts
- Vascular endothelium
Functions of macrophages in inflammation
Phagocytosis
Antigen presentation
Stim of fibroplasia and fibrosis
Why do macrophages accumulate in tissues?
- Inability to lyse irritants
- Antigen-antibody complexes form tissue grains
- Survival of infectious agents within macrophages
What are the two subtypes of macrophage?
A - epithelioid cells (maybe binucleate, 1° secretory)
B - giant cell (multinucleated cells, fusion of macrophage, in tissues w/ stable foreign matter)
What is granulomatous inflammation?
Chronic inflammation caused by organisms of low virulence but great persistance or implanted forgein bodies. Macrophage is main effector cell.
Histology of granuloma
- Central core of irritant/agent
- Chronic inflammatory cells surrounding core (macrophages, lymphocytes, plasma cells, eosinophils, calcification
- Outer fibrous capsule
What are the 4 stages of tissue repair?
1 - removal of necrotic debris
2 - Ingrowth of immature blood vessels
3 - Production of immature scar tissue
4 - Production of mature scar tissue
What cells are involved in tissue repair?
- Fibroblasts (organisation)
- Endothelium (proliferation, angiogenesis)
What protein is produced by fibroblasts?
Collagen
Why are horses susceptible to mass granulation tissue formation?
They have lots of acting fibroblasts, unknown why - called ‘proud flesh’.
What are fibroplasia and fibrosis?
Granulation tissue replace by immature fibrous tissue (fibroplasia) and then mature fibrous tissue to form mature scar tissue (fibrosis).
What factors effect healing?
- species effected
- age
- nature of the tissue damaged
- extent of tissue damaged
Regeneration vs repair
Repair - replacing damaged tissue with fibrous scar tissue (fibrosis)
Regeneration - replacing damaged tissue with normal tissue of the same type
Stages of skin wound healing
Primary Union = Healing by first intention
1 - haemostasos
2 - inflammation
3 - repair
4 - consolidation/reconstruction
