Lecture 11 2/21/24

Question 1

What are the mechanisms of chronic inflammation?

Answer 1

-persistance/resistance
-isolation in tissue
-unresponsiveness
-autoimmunity
-idiopathic

Question 2

Which stimuli can lead to chronic inflammation?

Answer 2

-infectious agents
-foreign material
-self-antigens

Question 3

What is the pathogenesis of chronic inflammation?

Answer 3

-persistent stimulus
-continued production of inflammatory mediators
-continued recruitment of inflammatory cells

Question 4

What change is seen in endothelial cell adhesion molecules during chronic inflammation?

Answer 4

-ICAM1 switches to VCAM1
-VCAM1 binds to VLA1 on lymphocytes

Question 5

Which cell types are involved in chronic inflammation?

Answer 5

-macrophages
-eosinophils
-lymphocytes
-plasma cells
-fibroblasts
-endothelial cells

Question 6

Which cells replace neutrophils in chronic inflammation?

Answer 6

-macrophages
-lymphocytes
-plasma cells

Question 7

How long must inflammation remain unresolved for other cells to arrive to replace neutrophils?

Answer 7

24-48 hrs

Question 8

What characterizes granulomatous inflammation?

Answer 8

-epithelioid macrophages
-multi-nucleated giant cells

Question 9

What can cause granulomatous inflammation?

Answer 9

-fungi
-mycobacteria
-foreign material

Question 10

How does IFN-gamma produced by TH1 cells differ from IL-13 produced by TH2 cells?

Answer 10

-IFN-gamma activates macrophages and is pro-inflammatory
-IL-13 suppresses macrophage functions and is anti-inflammatory

Question 11

What are the characteristics of nodular granulomas?

Answer 11

-TH1-based granulomas
-gray to white-tan, round, firm/hard nodules
-may or may not have central core of necrotic cell debris

Question 12

What are the general characteristics of granulomas?

Answer 12

-well organized and discrete
-epithelioid macrophages and/or multi-nucleated giant cells in inner layer
-lymphocytes and plasma calls in outer layer
-surrounded by fibrous capsule
-possible center necrosis

Question 13

What are the characteristics of pyogranulomas?

Answer 13

-chronic-active
-acute inflammation + granulomatous inflammation

Question 14

What are the characteristics of diffuse granulomas?

Answer 14

-TH2-based granulomas
-gray to white, expansile but poorly demarcated, firm
-widespread distribution with no distinct capsule

Question 15

What are the characteristics of eosinophilic and granulomatous chronic inflammation?

Answer 15

-have both eosinophils AND epithelioid and/or multi-nucleated giant cells
-can be diffuse or nodular
-associated with parasites
-abnormal immune response

Question 16

What are the characteristics of eosinophilic chronic inflammation?

Answer 16

-green appearance grossly
-eosinophilic myositis
-caused by parasites

Question 17

What are the characteristics of plasmacytic chronic inflammation?

Answer 17

-involves plasma cells
-idiopathic or due to chronic bact. infection
-chronic-active or chronic suppurative

Question 18

What are the characteristics of lymphoplasmacytic chronic inflammation?

Answer 18

-lymphocytes and plasma cells
-common end stage of inflammation
-not apparent grossly

Question 19

What are the potential causes of lymphoplasmacytic inflammation?

Answer 19

-viruses
-immune-mediated
-idiopathic
-end stage of other inflamm. processes

Question 20

What is the gross appearance of fibrosis/fibrous tissue?

Answer 20

-pale
-indented
-depressed

Question 21

How do the main characteristics of acute vs chronic gross appearance differ?

Answer 21

acute: redness, edema, fibrin, pus
chronic: fibrosis, granulomas, abscess

Question 22

What are the effects of inflammation?

Answer 22

-fever
-hematologic changes
-sepsis
-disseminated intravascular coagulation/DIC
-acute phase proteins
-neoplasia
-immune disorders

Question 23

What are the characteristics of fever?

Answer 23

-not the same as hyperthermia
-“thermostat reset” mediated by IL-1, IL-6, and prostaglandins
-can be harmful

Question 24

What are the benefits of fever?

Answer 24

-inhibit bact. growth
-increased leukocyte killing efficiency

Question 25

What is inflammatory-driven neoplasia?

Answer 25

-chronic inflammation associated with development of neoplasia
-occurs due to continued exposure of inflamed tissues to ROIs, leading to DNA damage
-inflamm. cytokines induce proliferation of non-immune cells