Lecture 25: GI Histology III

Question 1

What are the functions of Paneth cells?

L25 S6

Answer 1

• secretes lysozyme to increase permeability of bacteria
• secrete defensiveness to increase membrane permeability of target organisms
• secretes TNF-α
• may phagocytize some microorganisms

Question 2

What is the primary immunoglobulin produced by GALT and what response does it create?

L25 S14

Answer 2

• IgA

- does not stimulate complement cascade but instead coats microorganism preventing it from binding to epithelium

Question 3

What are Peyer’s patches?

L25 S13

Answer 3

-lymphoid structure under the mucosal surface

Contains:

• B-cells
• T-cells
• M cells: sample antigens and present them to APCs
• APCs (antigen-presenting cells)