Week 3 - Chronic Inflammation

Question 1

Which of the 4 signs of acute inflammation is present in chronic inflammatio?

Answer 1

Tumor and dolor

Question 2

How does chronic inflammation arise? (3)

Answer 2

• May take over from acute inflammation if the injurious agent is not removed
• Arises “de novo”
• Develops alongside acute inflammation

Question 3

When might chronic inflammation arise “de novo”?

Answer 3

Some autoimmune conditions
Some chronic infections
Prolonged exposure to toxic agent, e.g. silicon breast implants

Question 4

What types of cell are seen in chronic inflammation?

Answer 4

1. Macrophage
2. Lymphocytes (T and B)
3. Eosinophils
4. Giant cells
5. Fibroblasts/myofibroblasts

Question 5

Which is the major cell type seen in chronic inflammation?

Answer 5

Macrophages

Question 6

What are the functions of macrophages?

Answer 6

Phagocytosis
Secrete cytokines/complement components
Present antigens
Stimulate angiogenesis
Induce fibrosis/fever/acute phase reaction

Question 7

Are the presence of T+B lymphocytes in the tissues always a sign of infection?

Answer 7

No - always present

Question 8

How do B lymphocytes appear histologically?

Answer 8

Abundant ER and Golgi, for protein synthesis

Question 9

What is the function of B lymphocytes?

Answer 9

Differentiate into plasma cells - secrete antibodies

Produce cytokines

Question 10

What is the function of T lymphocytes?

Answer 10

T-helper cells release cytokines + express CD4 receptors

T killer cells kill abnormal/infected cells

Question 11

What are the 3 types of giant cell?

Answer 11

Touton
Foreign body giant cell
Langhan’s

Question 12

What is a giant cell, and when are they seen?

Answer 12

A large, multi-nucleated cell formed from the fusion of many macrophages.
Seen in granulomatous infection

Question 13

Describe the characteristic appearance of a Langhan’s giant cell

Answer 13

Nuclei around the periphery in a horseshoe shape

Question 14

How are the nuclei arranged in a foreign body giant cell?

Answer 14

Randomly

Question 15

What type of foreign body are typical of a TB infection?

Answer 15

Langhan’s

Question 16

Is a foreign body always inside a foreign body giant cell?

Explain

Answer 16

No

May be attached to the outside if it is hard to digest

Question 17

How are the nuclei arranged in a Touton giant cell?

Answer 17

Arranged in a ring towards the centre

Question 18

Where do Touton giant cells occur? Which other cell type do they form lesions with?

Answer 18

Where there is high lipid content.

Foam cells.

Question 19

What are the 2 major unwanted effects of chronic inflammation?

Answer 19

Fibrosis and impaired function

Involvement of inappropriate immune response

Question 20

What is fibrosis, and when does it occur?

Answer 20

Excess fibrous tissue

Occurs when fibroblasts are stimulated to by cytokines to produce excess collagen

Question 21

What are the benefits of collagen in chronic inflammation?

Answer 21

Walls off infected areas

Replaces damaged tissue with a fibrous scar

Question 22

When can collagen be a problem in chronic inflammation?

Answer 22

When it replaces parenchymal tissue - impairs organ function

Question 23

Give two example of when inflammation occurs as an effector of an inappropriate immune response?

Answer 23

Allergies - attacks innocuous targets

Autoimmune - attacks own cells

Question 24

Define granulomatous inflammation

Answer 24

Inflammation in which granulomas are seen

Question 25

Why may a granuloma occur?

Answer 25

When particles are present which are poorly soluble or difficult to eliminate - granuloma forms around the particle.

Question 26

What cells are present in the centre of a granuloma?

Answer 26

Mononuclear cells

Question 27

What are the two types of granuloma?

Answer 27

Foreign body granuloma | Hypersensitivity/immune type granulomas

Question 28

Where might a foreign body granuloma occur?

Answer 28

Around non-antigenic material, e.g. surgical thread

Question 29

Which cells are present in a foreign body granuloma?

Answer 29

Macrophages - always in chronic inflamm. Foreign body giant cells - it's in the name! Epitheloid cells - always in granulomas Fibroblasts - always in chronic inflam.

Question 30

Which sorts of cell occur in very small number (if at all) in foreign body granulomas?

Answer 30

Lymphocytes

Question 31

List the cell types found in immune type granulomas

Answer 31

``` Macrophages Giant cells Epitheloid cells Fibroblasts (not as many as foreign body granulomas) Lymphocytes - unlike FBGs ```

Question 32

What occurs in the centre of immune type granulomas?

Answer 32

Caseous necrosis

Question 33

Where do immune type granulomas form?

Answer 33

Around insoluble antigenic material

Question 34

Why might granulomas be harmful?

Answer 34

Occupy parenchymal space

Question 35

What is chronic inflammation?

Answer 35

The chronic response to injury, with associated fibrosis