Sunday, March 3, 2013
Innate and Adaptive Immunity in Inflammatory Bowel Disease
In the next few weeks our class will be discussing inflammatory bowel disease (IBD). IBD is actually a group of diseases characterized as the chronic inflammation of a the bowel, which leads to pain and some very unpleasant problems. Some of the most common are Ulcerative colitis and crohn disease. Essentially the cause of IBD is a dysregualtion of the immune system in the gastrointestinal tract which causes intestinal inflammation.
The paper proposes the cross-regulation or interaction between the innate and adaptive immune systems. The first proposed mechanism the review proposes is that there is a mutation in a particular receptor of the intestinal tract called NOD2 which is part of the innate immune system and serves to detect components of bacterial cell walls. In addition patients with the NOD2 mutation did not have macrophages which suppressed the secretion of pro-inflammatory molecules called cytokines and thus experienced inflammation. Patients with IBD who have a mutation in the NOD2 receptor show a decrease in the expression of anti-microbial proteins which causes an increase in the number of bacteria which can cross the intestinal lining. This is the link to the adaptive immune system's involvement in IBD. Due to the defect in the innate immune system of the intestine more bacteria than usual are able to cross the intestinal lining and activate T-cells which in turn secrete pro-inflammatory cytokines to fight of the invading bacteria, and increasing inflammation of the intestine. In addition cells from the innate immune system can also secrete these cytokines and activate an adaptive immune response and increase inflammation.
Some studies have been done to study which cytokines are involved in IBD and further if blocking them is an effective treatment of IBD.
link to the paper: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3158392/
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This blog is so helpful and I liked it so much. In the next few days I will surely get further studies about this matter. My alternative breast cancer treatment center finds this very interesting. Thanks for sharing!
ReplyDeleteJust to add onto your blog, I found another interesting article about blocking the production of nitrate and why it is important.
ReplyDeleteScientist Find Key To Growth Of “Bad” Bacteria In Inflammatory Bowel Disease.
http://www.medicalnewstoday.com/releases/256184.php
In inflammatory bowel disease one of the key characteristics is inflammation and damage to the intestines by harmful bacteria such as E. coli. These harmful bacteria multiply quickly to vast numbers while the good bacteria found in our gut are mistakenly killed by the immune system.
The question that has troubled researchers for years is “why are harmful bacteria able to survive in the gut in IBD while good bacteria cannot? What abilities do harmful bacteria alone contain? ” The answer lies in the harmful bacteria ability to produce and utilize nitrate for energy and growth as opposed to oxygen.
IBD leads to the release of nitric oxide radical that can kill the “good” bacteria within our bodies since they require fermentation for survival. Harmful bacteria such as E.coli however have found a way to utilize these nitric oxide radicals. Nitric oxide radicals are very powerful yet very unstable and eventually they will decompose into nitrate which the E.coli can uses to thrive and grown.
This was important knowledge for researchers aiming to treat IBD. Possibly by targeting and blocking the metabolic pathways that generates nitric oxide and nitrate researchers can normalize the environment and reduce the amount of molecules used to feed harmful gut bacteria in IBD.