Chronic Inflammation

Question 1

What is chronic inflammation

Answer 1

Inflammation over a prolonged period, during which time there are attempts at repair and tissue damage

Question 2

List and describe the causes of chronic inflammation

Answer 2

• Persistant infection (microorganisms difficult to eradicate)
• Immune mediated inflammatory diseases (e.g. bronchial asthma)
• Prolonged exposure to potentially toxic agents (both endogenous and exogenous)

Question 3

What are the key features of chronic inflammation?

Answer 3

• Infiltration with mononuclear cells (macrophages, plasma cells, lymphocytes)
• Adaptive immunity involvement (B and T cells)
• Tissue descruction
• Attempts at healing with connective tissue replacement of damaged tissue

Question 4

Which cells have the central role in chronic inflammation?

Answer 4

Macrophages

Question 5

Describe monocyte arrival and activation

Answer 5

Monocytes arive at site of inflammation around 48H after onset. They differentiate into macrophages. Macrophages are activated by a variety of stimuli (like cytokines)

Question 6

What are the results of activating macrophages?

Answer 6

• Elimination of microbes
• Initiation of repair process
• Increased levels of lysozomal enzymes, ROS, nitrogen species, cytokines, GFs and other mediators of inflammation

Question 7

Describe the role of lymphocytes in chronic inflammation

Answer 7

They have a role in perpetuating inflammation. Plasma cells produce antibodies against microbes or altered tissue components.

Question 8

What are the roles of eosinophils and mast cells in chronic inflammation

Answer 8

Eosinophils contribute to tissue damage

Mast cells seccrete cytokines and other factors and perpetuate inflammation

Question 9

Why MUST chronic inflammation be treated?

Answer 9

It causes tissue damage (even when there are no harmful stimuli)or amplifies tissue damage and worsens the situation if left untreated