Chronic inflammation Flashcards
(28 cards)
Which 3 cell types participate in tissue repair during chronic inflammation?
- Fibroblasts
- Endothelial cells
- Epithelial cells
Which cell type dominates chronic inflammation?
Macrophages
Kupffer cells
Macrophages in liver
Langerhans cells
Macrophages/dendritic cells in skin
Classical pathway of macrophage activation
- Initiated by release of INF-y from TH1 lymphocytes
1) Microbicidal (ROS, NO)
2) Inflammation (IL-1, IL-12, and IL-23)
Alternative pathway
- Initiated by IL-4 and IL-13 released b y TH2 lymphocytes
- M2 macrophages perform tissue repair (NOT microbicidal)
1) Tissue repair (TGF-B)
2) Anti-inflammatory (TGF-B and IL-10)
[Minor] Angiogenesis (FGF)
Function of epithelioid macrophages
Secretion (NOT phagocytic; have diminished phagocytic activity)
Langhans cell types
Multinucleated giant cells in a horseshoe-shape
Which two cytokines recruit lymphocytes and from where do they come?
TNF and IL-1
from Macrophages
(Lymphocytes also make TNF)
TH1 cells
Produce IFN-y
Classical macrophage activation
Th2 cells
Secrete IL-4, IL-5, and IL-13 -> recruit/activate eosinophils
Alternative macrophage activation
Th17
IL-17 -> neutrophil and monocyte recruitment
Perivascular cuffs
Ring of lymphoplasmacytic inflammation around vessel in the brain
Which two cytokines are primarily responsible for recruiting eosinophils?
IL-5 and eotaxin
Lymphoplasmacytic inflammation occurs in
1) Mucosal regions
2) Brain (perivascular cuffs)
Examples of lymphoplasmacytic inflammation
1) Inflammatory bowel disease
2) Granulomatous meningoencephalitis (misnomer)
3) Gingivitis in cats
4) Lentiviral pneumonia in sheep / arthritis in goats
5) Autoimmune-mediated chronic inflammation (i.e. Lupus)
Granulomatous inflammation
Shift from neutrophils to macrophages/lymphocytes/multinucleated cells
Diffuse (lepromatous) granulomatous inflammation
- (Epithelioid) macrophages w/ few other cells
- i.e. Johnes disease -> epitheliod macrophages replace lamina propria
Difference between granulomas and pyogranulomas
Pyogranulomas also contain:
- Neutrophils
- Fibrin
- Plasma proteins
Pyogranulomas are found in
- Blastomyces dermatitis
- FIP
Describe the gross appearance of pyogranulomas
White nodules
Structure of a granuloma
Outer to in:
Lymphocytes
Fibrosis
Lymphocytes/macrophages
Central necrotic debris
Nodular (Tuberculoid) Granulomas
Center has giant cells and epitheloid macrophages
Diffuse granulomatous
Granulomas in sheets instead of nodules