Researchers uncover a potentially important lead: "Elimination of a molecular gatekeeper leads to the development of arthritis in mice ... The newly discovered gatekeeper is a protein that determines the fate - survival or death - of damaging cells that mistakenly attack the body's own tissues and lead to autoimmune disorders such as arthritis. ... An added bonus is that this finding may help in the search for new treatments for other autoimmune disorders, such as lupus. ... The protein at the center of the new finding, known as G alpha q, is part of a larger signaling pathway that Lund and collaborators from across the United States and China investigated in mice. G alpha q regulates B cells, one type of immune cell that the body maintains to fight off invaders like bacteria, viruses and parasites. While most B cells help defend the body, some B cells are autoreactive - they turn against the body's own tissues. ... Several new studies expanding on the current finding are in the works, including testing whether drug compounds that alter the expression or activity of G alpha q in mice can slow the development of autoimmunity. Beyond preclinical testing in mice, researchers also hope to start screening G alpha q levels in patients to learn more about how the protein works in humans."