L10 Chronic inflammation

Question 1

Types of chronic inflammation

Answer 1

diffuse
granulomatous
foreign
immune-> caseous, non caseous

Question 2

Cell types involved in chronic inflammation

Answer 2

cells with a single nucleus
monocytes/macrophages
lymphocytes
Eosinophils

Mast cells

Question 3

Eosinophils

Answer 3

− Parasitic infection and allergic reactions 


− Granules release major basic protein toxic to parasites and causes epithelial cell necrosis 


Question 4

Monocytes

Answer 4

immature mononuclear phagocytes found in blood circulation

recruited and differentiate into macrophages in response to inflammation

Question 5

Tissue macrophages

Answer 5

• Ingest and eliminate microbes and dead tissues 

• Initiate the process of tissue repair 

• Display antigens to T- lymphocytes and respond to signals from T cells 

• May produce cytokines that will activate T-lymphocytes
• Respond to signals from T-lymphocytes
• Die or ‘wander off ’ in the absence of inflammatory stimulus, but remain if stimulus persists

Question 6

Tissue macrophage activation

Answer 6

• M1 Classical activation by microbial products and IFN-Υ
Role: Microbicidal processes –ingest and eliminate microbes
Contribute to inflammation

• M2 Alternative activation by other cytokines (IL-4 and IL- 13)
− Principle role in tissue repair

Question 7

Lymphocytes

Answer 7

• Main stimulus is infection and inflammation
Respond to cytokines being reduced at the site of injury 

• Recruited from the blood into the peripheral tissues 

• B-lymphocytes develop into plasma cells and secrete antibodies 

• CD4+T-lymphocytes become activated and secrete cytokines- stimulate cells at the site of infection

Question 8

TH1

CD4+ T-lymphocytes

Answer 8

• Secrete IFN-Υ 

• Classical macrophage activation-stimulate M1 

• Defense against bacteria, viruses and autoimmune disease 


Question 9

TH2

CD4+ T-lymphocytes

Answer 9

• Secrete IL-4, IL-5, IL-13 

• Alternative macrophage activation, M2
• Defense against helminthic (intestinal) parasites and allergic inflammation 


Question 10

TH17

CD4+ T-lymphocytes

Answer 10

• Secrete IL-17 


* Leukocyte recruitment-chemotactic factor 


Question 11

Morphological features of chronic inflammation

Granulomatous inflammation Morphology

Answer 11

• Could have a central zone of necrosis (caseating or non- caseating) 

• Epithelioid cells-pink granular cytoplasm 

• Surrounding lymphocytes 

• Multinucleated giant cells 

− Langerhan or foreign body
• Fibroblasts and collagen

Question 12

Granulomatous inflammation

• Caseating granuloma morphology

Answer 12

surrounded by a spherical mass of cells: macrophages , epithelioid cells, giant cells, lymphocytes