2.2 Chronic Inflammation Flashcards
1
Q
Chronic inflammation is characterized by presence of:
A
-lymphocytes, plasma cells in tissue
2
Q
Cytokines in Th1 branch, their purposes
A
- IL12 to create Th1 cells
- Th1 cells make IFN-G and IL2
- IFN-G: activate macrophages, class switch to IgG
- IL2: activate CD8 T cells
3
Q
Cytokines in Th2 branch, their purposes
A
- IL4 to make Th2
- Th2 makes IL4, IL5, IL10, IL13
- IL4: class switch IgE
- IL5: class switch IgA
- IL10: inhibit Th1 (also with TNF-B stop inflammation)
- IL13: asthma
4
Q
How to CD8 cells kill?
A
- secrete perforin and granzyme
2. Fas ligand binds Fas death receptor on target cells
5
Q
How do B cells become activated?
A
2 ways:
- Antigen binding by surface IgM or IgD
- Antigen presentation to CD4 helper T cell
- requires CD40/CD40L and IL4/IL5
6
Q
Granulomatous inflammation
- defining feature
- other cells
- divided into what types
A
- subtype of chronic inflammation
- Aggregation of epitheloid histiocytes! (pink cytoplasm)
- surrounded by giant cells and rim of lymphocytes
- divided into caseating/ non-caseating
7
Q
epitheloid histiocyte
A
- activated macrophage resembling epithelial cell
- pink cytoplasm
- characteristic of granuloma
8
Q
Non-caseating granuloma
- histology
- differential
A
- histology: epithiloid histiocytes still have nuclei, so no necrosis. (as opposed to caseating)
- Rxn to foreign material (eg breast implant leak into lymphatics)
- sarcoidosis
- beryllium exposure
- crohn disease
- cat scratch disease
9
Q
Caseating granuloma
- histology
- differential
A
- histology: epithiloid histiocytes lose nuclei because necrosis. (as opposed to non-caseating)
- TB!
- fungal infections!
10
Q
Granuloma formation steps
A
- macrophages present antigen to CD4 cells, MHC II
- macrophages secrete IL12 to make Th1 cells
- Th1 cells secrete IFN-G to activate macrophages into epithiloid histiocytes and giant cells
