Mucosal Immunology Flashcards
What is mucosa-associated lymphoid tissue (MALT)?
1 - group name for all lymphoid tissue grouped together
2 - lymphoid tissue close to mucosal membranes
3 - lymph nodes in mucosa
4 - small concentration of lymphoid tissue in submucosal membranes
4 - small concentration of lymphoid tissue in submucosal membranes
- located in various submucosal membrane sites of the body, such as the gastrointestinal tract, nasopharynx, thyroid, breast, lung, salivary glands, eye, and skin
The mucosa-associated lymphoid tissue (MALT) is small concentrations of lymphoid tissue located in various submucosal membrane sites of the body, such as the gastrointestinal tract, nasopharynx, thyroid, breast, lung, salivary glands, eye, and skin. Why is MALT so important?
- in continual contact with the outside world
- continuously stimulated with antigens
Which types of cells populate the mucosa-associated lymphoid tissue?
1 - T cells, basophils and neutrophils
2 - Neutrophils, B and T cells
3 - Macrophages, neutrophils and T cells
4 - macrophages, neutrophils and B cells
2 - Neutrophils, B and T cells
Mucosa associated lymphoid tissue (MALT) is scattered around the body. Using the mnemonics below what are the sites where MALT is located?
LALT GALT NALT SALT BALT VALT
LALT: Larynx associated lymphoid tissue
GALT: Gut associated lymphoid tissue
NALT: Nasal associated lymphoid tissue
SALT (Skin-associated lymphoid tissue), CALT (conjunctiva-associated lymphoid tissue), TALT (Eustachian tube-associated lymphoid tissue),
BALT (Bronchus-associated lymphoid tissue)
VALT (Vulvo-vaginal associated lymphoid tissue)
What is the difference between effector and memory cells in the immune system?
- effector cells are those involved in the right now action such as plasma and activated cytotoxic T cells
- memory cells are cells that remain in case the same antigen is presented again
There are a number of defence strategies of oropharynx and intestinal mucosa. The epithelial cells and tight junctions make up which component of the defence strategy?
1 - mucins
2 - antimicrobial proteins
3 - specialised cells
4 - mechanical barrier
4 - mechanical barrier
There are a number of defence strategies of oropharynx and intestinal mucosa. There is an extensively glycosylated protein that lines the surface of mucosa epithelial cells. Which component of the defence strategy are these part of?
1 - mucins
2 - antimicrobial proteins
3 - specialised cells
4 - mechanical barrier
1 - mucins
There are a number of defence strategies of oropharynx and intestinal mucosa. Cells including goblet cells, absorptive epithelial cells, M cells and Paneth cells are part of which component of the defence strategy?
1 - mucins
2 - antimicrobial proteins
3 - specialised cells
4 - mechanical barrier
3 - specialised cells
There are regional immune systems in the body. What is the name given for the group of tonsils, including the lingual and palatine tonsils, nasopharyngeal tonsils?
1 - Waldeyer’s ring
2 - Peyer´s patches
3 - Mesenteric lymph nodes
4 - Tensilular ring
1 - Waldeyer’s ring
There are regional immune systems in the body. One of these is a small mass of lymphatic tissue found throughout the ileum region of the small intestine
1 - Waldeyer’s ring
2 - Peyer´s patches
3 - Mesenteric lymph nodes
4 - Tensilular ring
2 - Peyer´s patches
There are regional immune systems in the body. There are lymph nodes that aggregate around the GI tract. What is this regional immune system called?
1 - Waldeyer’s ring
2 - Peyer´s patches
3 - Mesenteric lymph nodes
4 - Tensilular ring
3 - Mesenteric lymph nodes
- mesenteric relates to the folds of membrane located close to the GIT
Which of the following regional immune systems in the body contain germline centres for B and T cells?
1 - Waldeyer’s ring
2 - Peyer´s patches
3 - Mesenteric lymph nodes
4 - Tensilular ring
2 - Peyer´s patches
What is an effector site in the mucosa-associated lymphoid tissue (MALT)?
- site where activated immune cells are present (lamina propria)
- B, plasma and T cells
What is an inductor site in the mucosa-associated lymphoid tissue (MALT)?
1 - site where active B, T and plasma cells are found
2 - site where B and T cells are activated/induced
3 - site where B and T cells develop
4 - site where B and T cells go through central tolerance
2 - site where B and T cells are activated/induced
- naive cells and antigen presenting cells (APC) are located here
- APCs induce naive B and T cells at this location
- generally payers patch
What are the 2 locations in the GI tract where lymphoid tissue is most concentrated?
1 - oropharynx and terminal ileum
2 - nasopharynx and small bowel
3 - oropharynx and small bowel
4 - nasopharynx and terminal ileum
1 - oropharynx (Waldeyer’s ring) and terminal ileum (Peyer’s patches)
What is the lamina propria?
- area of connective tissue behind the epithelial cells of the GIT
- they contain activate immune cells
There is a specialised cell within the GI that is important for continually monitoring the microorganisms and eco-enviroment of the GIT. They are able to engulf antigens via endocytosis and then present the antigen to antigen presenting cells. What are these cells called?
1 - parietal cells
2 - M cells
3 - I cells
4 - payers cells
2 - M cells
- think M for monitoring
Once B and T cells have been activated in the payers patch they travel throughout the circulation before ending up in a site of the body that they are drawn to because of the receptors that change when the cells are activated. What location are they attracted to in the body?
1 - mesenteric lymph nodes
2 - kidneys
3 - spleen
4 - lamina propria in GIT
4 - lamina propria in GIT
- activated cells contain honing receptors to tell them where to go
What are the 2 induction sites in the GIT?
1 - mesenteric lymph nodes and M cells
2 - mesenteric lymph nodes and spleen
3 - payers patch and mesenteric lymph nodes
4 - payers patch and M cells
3 - payers patch and mesenteric lymph nodes
There is a cell contained within the epithelium of the GIT that are able to release granules containing antimicrobial peptides that are involved in regulating the gut microbiota. What are these cells called?
1 - M cells
2 - Paneth cells
3 - Goblet cells
4 - Epithelial cells
2 - Paneth cells
- remember Paneth release Peptides that are antimicrobial
On the epithelial cells of the GIT there are a group of pattern recognition receptors (PRR) that are specifically able to sample and monitor the gut microbiota, assessing for the risk of infection. Which PRR is this?
1 - toll like receptor 5
2 - toll like receptor 1
3 - NOD-5
4 - NOD-1
1 - toll like receptor 5
- able to tighten the tight junctions between epithelial cells
Where are the majority of payers patches located in the GIT?
1 - distal ileum
2 - proximal ileum
3 - jejunum
4 - duodenum
1 - distal ileum
There are a number of different lymphatic vessels that carry lymph and lymphocytes around the body. What is the name of the vessels where B and T cells enter the follicle contained within the payers patch?
1 - Low Endothelial Venules
2 - High Endothelial Venules
3 - Middle Endothelial Venules
4 - Intermediate Endothelial Venules
2 - High Endothelial Venules
Once a naive B and T cell is in the follicles of the payers patch they can be activated. How does this occur?
- M cell binds antigen and presents to APC
- APC presents antigen on MHC-II to B and/or helper T cells
- activates helper T cells
- B cell can be activated by T cells or independently
Once a B cell has been activated by the T helper cell, the T helper cell secretes cytokines that causes the class switching of antibodies from IgM or IgG to what antibody?
1 - stays as IgG
2 - IgA
3 - IgM
4 - IgD
2 - IgA
- most abundant antibody in the GIT
Once B and T cells have been activated they leave the inductions sites (payers patch and mesenteric lymph nodes) and enter the circulation via what vessels?
1 - Low Endothelial Venules
2 - High Endothelial Venules
3 - Middle Endothelial Venules
4 - thoracic duct
4 - thoracic duct
IgA is the main antibody involved in gut associated lymphoid tissue. What 2 functions is IgA able to perform?
1 - neutralise antigen and bind and place antigen back into lumen
2 - bind with M cell and activate B cells
3 - neutralise antigens and police the lamina propria
1 - neutralise antigen and bind and place antigen back into lumen
IgA is the main antibody involved in gut associated lymphoid tissue. Low levels of IgA in children has been associated with what?
1 - constipation
2 - irritable bowel syndrome
3 - food allergies
4 - inflammatory bowel disease
3 - food allergies
There is a growth factor that is involved in the tolerance to food antigens, and is able to do the following:
- regulate central tolerance in thymus
- maintains homeostasis of the naïve T-cell pool (peripheral tolerance)
- inhibits cytotoxic T cells (peripheral tolerance)
- maintains cell proliferation (B cells and innate cells)
What growth factor is this?
1 - fibroblast growth factor
2 - insulin
3 - transforming growth factor
4 - epidermal growth factor
3 - transforming growth factor
Once a B and T cell has been activated at the induction site (payers patch and mesenteric lymph nodes) what metabolite is produced?
1 - tryptophan
2 - retinoic acid
3 - bakuchiol
4 - eicosanoic acid
2 - retinoic acid
Once a B and T cell has been activated at the induction site (payers patch and mesenteric lymph nodes) they are exposed to the metabolite retinoic acid. What cell creates this and what vitamin is required?
1 - macrophages and vitamin A
2 - macrophages and vitamin D
3 - dendritic cells and vitamin A
4 - dendritic cells and vitamin D
3 - dendritic cells and vitamin A
Once and activated B and T cell have been activated and exposed to retinoic acid, they undergo synthesis of receptors. What 2 receptors are then exposed on the B and T cell surface membrane?
1 - chemokine CCR9 and integrin α4β7
2 - chemokine CCR19 and integrin α4β8
3 - interleukin 6 and integrin α4β7
3 - interleukin 1 and integrin α4β7
1 - chemokine CCR9 and integrin α4β7
- important in honing B and T cells from inductor to effector site
