Exam II Lecture 7 Flashcards
Peyer’s patches can serve as a site of _____ activation
T cell
what cells do Peyer’s patches utilize to transport antigens into it?
M-cells
what are M-cells?
what do they do?
what is the purpose of their role?
special epithelial cells which transport antigens or commensal bacteria from intestinal lumen into the Payer’s patch to initiate an immune response if needed
which type of T cell is within the walls of the epithelial cells?
CD8+
CD8+ T cells:
where are they formed?
what molecule binds by presenting peptides which gives this cell information to target non-self antigens?
when it becomes activated, what 2 cytokines does it secrete?
what do they produce and release to attack viral proteins and cause apoptosis?
thymus
MHC class I
TNF-a & IFN-y
cytotoxic granules
how many more microbial cells are there to human cells? (excluding RBCs)
10x
how many more microbial genes are there to human genes?
100x
where are TLRs located on epithelial cells?
basal membrane side
where are NLRs located in the intestine?
within epithelial cells
where are dendritic cells located in the intestine?
what do they express on their surface?
lamina propria (underneath epithelial layer TLRs
DC cells that express CD11b+ and CX3CR1+ recognize antigens in what way? what type of T cell do they activate?
what cytokines do DC cells release to the T cell? what cytokines does this cause the T cell to release?
They can reach into lumen and engulf antigens
T-helper 17 cells
TGF-b & IL-6
IFN & IL-17
DC cells that express CD103+ and CX3CR1 recognize antigens in what way?
These DC cells induce T-cell activation, what does the DC cell produce?
this production induces naive T-cell formation into what type of T cells?
What do these resulting T cells (with B-cells) produce?
antigens that pass through the epithelial layer
TGF-b & retinoic acid
T-regulatory cells
IgA
Defect in the function of T-reg cells are associated with? (loss of immune function)
defects in autoimmunity such as inflammatory bowel disease
what cytokine do T-cells produce for preventing unnecessary inflammation?
IL-10
After use of antibiotics, what protein production might be compromised? why?
IgA
IgA is induced by microbiota in the gut and production is dependent on the presence of microbiota
if an antigen comes in contact with the lamia propria (e.g. M-cell transcytosis), DC cells would respond and activate what type of cell?
Activated T-helper cells then activate B-cells via self-recognition and ___-____ _________.
once this occurs, B-cells can isotype switch to produce what?
This entire process is called?
CD4 T cells
CD40-CD40L mechanism
IgA
T-cell Dependent IgA class switching in the Gut
When a bacterium enters the lamia propria, DC TLR response is initiated, which stimulates the release of cytokines such as? (3)
these three cytokines induce isotype switching on B-cells to produce?
This entire process is called?
APRIL, TGF-B, and BAFF
IgA
T-cell Independent IgA class switching in the Gut
IgA must bind to what receptor to be transported into the gut lumen?
Poly-Ig receptor
T/F IgA is a main immunoglobulin protecting mucosa
True
Adaptive immunity to pathogens in the intestinal lumen is mediated in part by antibodies.
Which of the following statements about these antibodies is false?
A. IgA is a main immunoglobulin protecting mucosa
B. Treg cells provide help for IgA production
C. IL-12 is required for B cells to class switch to the isotype the antibodies to IgA
D. Binding to Poly-Ig receptor is required to transport IgA into the gut lumen
E. BAFF and APRIL stimulate T cell independent switching to IgA
C
patients with primary immune deficiency will have B-cells but will not produce ______
antibodies
epithelial cells can have two different functions in the body. However, they cannot effectively do both functions simultaneously. what are the two different cell functions?
immune cells and digestive cells
how are IgA important for allowing our epithelial cells to focus on nutrient absorption?
IgA allows us to protect against microbes and prevents the need for epithelial cells to act in immunity functions
