Mucosal Immunity Flashcards

1
Q

Why is the mucosa vulnerable?

A

Fragility and permebaility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Physiological functions of mucosal tissue?

A

Gas exchange
Food absorption
Sensory activities
Reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Examples of mucosal tissues?

A
Mammary gland
Salivary gland
Kidnye
Uterus/bladder/vagina 
Conjunctiva
Trachea
Lungs 
Intestine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Anatomical features of gut mucosal system?

A

Organised lymphoid structures unique to mucosal sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Effector mechanisms of gut lymphocytes?

A

Activated/Memory T cells predominate

Natural effector/regulatory T cells- in organised tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where is the Peyer’s patch?

A

Only in small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are Peyer’s atches covered in?

A
  • Covered by an epithelial layer containing M cells which have membrane ruffles
  • Takes up antigens by endocytosis/phagocytosis and transported across M cells in vesicles
  • To dendritic cells which activate T cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Special skill of dendritic cells?

A

Can reach through epithelial layer to capture antigen from lumen of gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many compartments is mucosal immune system?

A

2
Epithelium
Lamina propria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Immune cells of lamina propria?

A
  • CCR9
  • Plasma cell
  • Dendritic cells
  • Mat cells
  • Macrophages
  • C4 T cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Immune cells of epithelial layer?

A
  • CD8 T cell expressing alpha E:B7 integrin and CCR9

- Dendritic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens to T cells when they are activated by dendritic cells after they’ve encountered antigens?

A

Enter Peyer’s patch from blood vessels

Drain through lymph nodes to thoracic duct ad return to gut via bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Most common Ig in GI tract?

A

IgA (80%) the IgM the IgG

Dimeric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What can IgA do?

A

Neutralize pathogens and toxins also while internalized in endosomes
-Can also export toxins and pathogens from lamina propria while being secreted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Special T cells in Gut?

A

Intra-epithelial lymphocytes (IELs) 90% are T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens after virus infects mucosal epithelium cell?

A
Infected cell displays viral peptide to CD8 IEL via MHC class 1 
-Activated IEL kills epithelial cell by Fas-dependant pathway
17
Q

What happens when mucosal immunity is dysregulated in infections?

A

Infection crosses mucosa and fuses to dendritic cells which shuttle viruse to regional lymph nodes, infection spreads to CD4+ lymphocytes, these viral infected cells go into blood stream and disseminate across body

18
Q

What is selective IgA deficiency?

A

Asymptomatic

Recurrent sino-pulmonary infection (coeliac disease x10)

19
Q

What does CVID stand for?

A

Common variable Immuno-deficiency

20
Q

What is CVID?

A

Recurrent Sino-pulmonary and GI infections (low IgA, M, G & E)

21
Q

What does XLA stand for?

A

X linked agammaglobulinaemia

22
Q

What is XLA?

A

Sinopulmonary and GI infection + devastating enteroviral infections (No B cells)

23
Q

What is chronic granulomatous disease?

A

Staph aureus/ inflammatory granulomas
Pneumonia
Abcesses

24
Q

Severe combined Immunodeficiency acronym?

25
What is SCID?
Defect in T & B cell immunity
26
What happens with IgE in allergies?
Secreted by plasma cells binds to mast cells which secrete signals to B cells to stimulate further IgE production. During ingestion antigen diffuses into blood diseminating causing urticaria and anaphylaxis
27
Coeliac disease profile?
Genetically linked Not an allergy Loss of villi Biopsy for gold standard diagnosis
28
2 examples of inflammatory bowel disease?
Crohn's disease | Ulcerative colitis
29
What is Crohn's disease?
Can affect any part from mouth to anus - Focal and discontinuous inflammation with deep fissures +- granulomas - Mediated by Th1 CD4+ T cells
30
What is ulcerative colitis?
Rectum and colon - starts in rectum and moves proximally
31
What do ulcerative colitis and Crohn's disease both produce in large amounts?
Inflammatory cytokines IL-1, IL-6 and TNF alpha
32
Treatment of inflammatory bowel disease?
-NSAIDS (Non- specific anti-inflammatory and immunosuppressive drugs) Steroids, azathioprine, methotrexate