Mucosal Immunology Flashcards
What are the mucosal-associated tissues?
Initates immune responses to specific antigens encountered along all muscoal surfaces
What are Gut-associated lymphoid tissue?
Component of the muscoa assoicated lymphoid tissue which works in the immune system to protect the body from invasio in the gut
What is the function of the Lamina propria?
Composed of structural protein molecules, nerves and veins that carries blood to the epithelium while holding cells in place and binding them to the smooth muscle
What is the function of the musocal epithelial?
- Physical barrier
- Tight junctions prevent pathogen entry
What is the function of goblet cells?
- Secret mucus
- Secrete anti microbial peptides (AMPs)
What are the purpose of enterocytes in the epithelial barrier?
- Intracellular TLR4 expression
- Active shuttling of IgA from LP
What are enterocytes?
Interestinal absoptive cells that ensure the uptake of ions, water, nutrients, vitamins and absorption of unconjugated bile salts
What are the functions of Paneth cells?
- Secrete AMPs
- Support the regeneration of the epithelium
What are Paneth cells?
Secretory cells found in the crypts of Lieberkuhn adjacent to the intestinal stem cells
What specialised cells are found within the gut epithelium?
- Microfold cells
Where are microfold cells found?
Above follicles (follicle-associaed epithelium - FAE)
What is the function of microfold cells?
Pass antigens to immune cells in the LP - Transcytosis
How many lymphocytes are in one epithelial cell?
10
Where are Intra-epithelial lymphocytes found (IELs)?
On the basolateral side of the epithelium
What is the difference between alpha beta T cells and gamma delta T cells
alpha beta T cells are unqiue
gamma delta T cells are less diverse
Where is gamma delta T cells present?
Epithelial layers
What is the function of gamma delta T cells?
Maintain epithelial barrier and promote T cell responses
- Role in cancr immunosurveillance
What is Germinal centre controlled by?
Chemokines
What are Germinal Centres?
Specialised microstructure that form in secondary lymphoid tissues
- Produces long-lived antibody secreting plasma cells and memory B cells
What does B cells undergo in a lymph node germinal centre
- Mitosis
- Affinity maturation
- Class switch recombination (mainly to IgG)
- Differentation to plasma cells and memory cells
What cells are in Germinal Centre?
- B Cell
- T FH cells (provide help to centrocytes)
- FDCS (follicular dendritic cells) (to present antigen)
- Macrophages (To remove apoptotic B cells)
What is Peyer’s patches?
Specialised aggregates of lymphoid follicles in the lamina propria
What is Crytopatches?
Small single follicles
- Base of crypts
What are isolated lymphoid follicles?
Sites for induction of muscoal immune responses
