Genome complexity: educating T cells (Introduction)

by David Turell , Friday, April 24, 2015, 18:21 (3290 days ago) @ David Turell

Our immune system must differentiate between 'good' and 'bad' bacteria:-
"An international research team led by Weill Cornell Medical College investigators has discovered an answer to why the human immune system ignores roughly 100 trillion beneficial bacteria that populate the gastrointestinal tract. The findings, published April 23 in the journal Science, advance investigators' understanding of how humans maintain a healthy gastrointestinal tract, and may provoke new ways to treat inflammatory bowel disease—including Crohn's disease and ulcerative colitis—whose origins have been mysterious and treatment difficult.
 
"The investigators studied T cells—critical components of the adaptive immune system—which have the capacity to recognize, eliminate and remember foreign microbes that invade our bodies. T cells are named after the thymus, an organ where they develop and are taught not to attack normal human tissues and organs, leaving them free to target and eradicate disease-causing foreign invaders. One question that had puzzled scientists until now is how these cells learn to ignore beneficial bacteria in the intestine that are also foreign, but not harmful.-"In the study, the research team discovered that once they leave the thymus, T cells are again educated in the gastrointestinal tract, or gut, to leave beneficial bacteria alone. This dual education strategy is vital to supporting healthy immune function, the investigators say. -http://medicalxpress.com/news/2015-04-immune-cells-beneficial-bacteria.html