Immunology of Inflammatory Bowel disease

Question 1

What is the difference in pathology between Crohn’s disease and Ulcerative Colitis?

Answer 1

The colon of Crohn’s diseased patients has plaques, fat wrapping around the intestines, and the wall is much thicker.
Ulcerative Colitis has ulceration, crypt distortion, and no fat wrapping.

Question 2

What is a M cell?

Answer 2

A M-cell is found in follicle-associated epithelium (Peyer’s patch) and through M-cells a small amount of bacteria can enter a lymphoid follicle and are presented by APCs (sampling of the microbiome). There will be IgA produced that coat the bacteria so they can’t attach to the cells (but are present because we need them).

Question 3

What are the beneficial functions of the gut microbiota?

Answer 3

Synthesize essential metabolites, break down plant fibers in food, inactivate toxic substances in food or made by pathogens and prevent pathogens from benefiting from the resources of the human gut.

Question 4

What are possible causes of IBD?

Answer 4

Genetics, microbiota, diet, and state of your immune system.

Question 5

Which mutations are key risks in IBD?

Answer 5

NOD2 mutations. NOD normally inhibits TLR2 but when mutated it doesn’t so there will be inflammation due to IL-12.

Question 6

What therapeutic strategies are there for IBD?

Answer 6

Antibiotics to remove bad bacteria, probiotics and fecal transplantation to introduce good bacteria.