Hi, have you read this,
A non-pathogenic bacterium is capable of triggering an autoimmune disease similar to multiple sclerosis in the mouse, the model animal which helps to explain how human diseases work. This is what a group of researchers from the Catholic University of Rome, led by Francesco Ria (Institute of General Pathology) and Giovanni Delogu (Institute of Microbiology), have explained for the first time in a recently published article on the Journal of Immunology.
Multiple sclerosis is caused by an inflammatory reaction provoked by the immune system, leading to disruption of the coating of the nerve fibres in the Central Nervous System.
"We do not know what causes multiple sclerosis", explains Francesco Ria, immunologist of the Catholic University. "We know that there exists a genetic factor and an environmental factor, but we do not yet possess a satisfactory theory which can explain how exactly this environmental factor works".
Currently, there are two competing theories in the field: according to a first hypothesis, a virus hides within the brain and what causes the disease is the immunologic antiviral reaction. On the other hand, the second hypothesis states that a viral or bacterial pathogen similar to specific molecules of the Central Nervous System causes an inflammation which provokes a reaction of the immune system. This reaction ends up destroying the brain cells. The latter is called the autoimmune hypothesis. you can read the full report at http://www.medicalnewstoday.com/articles/180584.php