Scientists have identified a chain reaction that explains why our own bodies can turn against healthy cells, potentially transforming the way we look at autoimmune diseases and the way we treat them.
The reaction, discovered after four years of research in mice, has been described as a “Runaway train” where one error leads the body to develop a very efficient way of attacking itself.
Ordinarily these cells produce antibodies and program the immune cells to attack unwanted antigens, but scientists found an ‘override switch’ in mouse B cells that distorted this behaviour and caused autoimmune attacks.
The team used what’s known as a ‘confetti’ technique in their imaging, where fluorescent marker proteins were used to track different B cells in the body.
B cell clones actually battle each other out inside these centres so the body can determine which antibody is best suited to fight the threat, and in the case of this study that meant one colour of protein winning out against the others.
“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.
Eventually, blocking the germinal centres in some way could put a break in the vicious cycle that autoimmune diseases create.