Autoimmune diseases are triggered by our bodies’ strange tendency to attack its own healthy cells, as if they were diseased. This condition has puzzled scientists for a long time. Why does it happen? According to the research conducted on mice, B cells, that normally produce antibodies, possess an “override switch” that causes the autoimmune attack.
“Once your body’s tolerance for its own tissues is lost, the chain reaction is like a runaway train,” says Michael Carroll from Boston Children’s Hospital and Harvard Medical School. “The immune response against your own body’s proteins, or antigens, looks exactly like it’s responding to a foreign pathogen.”
The model of the autoimmune disease used in this research was lupus autoimmune disease since it is considered to be a classic type.
When B cells sense a foreign body, they swing into action in clusters called germinal centres. The main problems appear when the body wrongly identifies a normal protein as a potential threat, then the B cells start producing autoantibodies which attack our own organism.
“Over time, the B cells that initially produce the ‘winning’ autoantibodies begin to recruit other B cells to produce additional damaging autoantibodies – just as ripples spread out when a single pebble is dropped into water,” says Degn.
What could be a possible solution is the blocking of the germinal centers and the immune system’s short memory, but this type of treatment is still not possible.
“This finding was such a surprise,” says Carroll. “It not only tells us that auto-reactive B cells are competing inside germinal centres to design an auto-antibody, but then we also see that the immune response broadens to attack other tissues in the body, leading to epitope spreading at the speed of wildfire.”
If you are interested in the whole research, click on this link; http://www.cell.com