11. Mucosal Immunology

Question 1

Structure and function of Peyer’s patches

Answer 1

• Lymphatic nodules
• Monitor intestinal bacteria populations and preventing the growth of pathogenic bacteria in the intestines
• Contain germinal centres for B- and T cells

-Inductive site for immune response

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Question 2

Structure and function M cells

Answer 2

transport antigens to subepithelial lymphoid structures

Question 3

Role of TGF beta

Answer 3

Function: suppression/tolerance
Target: T cells, Macrophages

Question 4

IgA antibody

Answer 4

• IgA is the main antibody in secretions
• IgA against food antigens provides immune exclusion
• IgA activates the complement system only weakly
• Secretion of IgA (coupled to J chain) depends on a trans-cellular transport mechanism

Question 5

Role of intestinal epithelial cells in immune function

Answer 5

Goblet cells produce mucus (acts as physico-chemical barrier)

Epithelial cells express TLRs
-TLR5 on basolateral surace

Question 6

T reg cells

Answer 6

Produce 1L-10 
maintaining food tolerance, class switch, TGF-beta

Question 7

Role of Th1 cells

Answer 7

produce IFN-gamma

kill virally infected epithelial cells

Question 8

Th17

Answer 8

• Produce IL-17 and IL-22.
• These cytokines and interact with receptors on epithelial cells to regulate the production of mucins or defensins (antimicrobial peptides).