- THURSDAY, Aug. 7 (HealthDay News) — B cells may be more
responsible for causing autoimmune diseases like lupus or rheumatoid
arthritis than initially thought, according to a new study.

The finding, published in the Aug. 7 online issue of the journal
Immunity, may give scientists a new path to pursue in finding ways
to stop the immune system's chronic attacks on the body's own tissue
during these diseases.

B cells, the source of damaging auto-antibodies, have long been thought
to remain quiet in autoimmune diseases unless they are given a kick-start
by T-cells. Researchers from Yale and Boston universities had found that
toll-like receptors recognize and react to “self” molecules, in particular
mammalian DNA and RNA. When this occurs, these receptors help activate B
cells that make the classical auto-antibodies of lupus.

These signals, like those from T-cells, start the autoimmune process in
B cells. In the new study, the researchers theorize that once activated in
this way, the B cells can subsequently recruit T-cells. This creates a
“vicious cycle” of chronic autoimmune disease in which the two types of
cell prod each other into action.

The findings could explain why autoimmune-disease treatments aimed at
T-cells have not done as well as those targeting B cells, the researchers
said.

More information

The U.S. National Library of Medicine has more about autoimmune diseases.