Exposure to staph bacteria could be a risk factor for lupus - a chronic inflammatory disease, say researchers. Staphylococcus aureus, is a germ commonly found on the skin or in the nose, sometimes causing infections. In the Mayo study, mice were exposed to low doses of a protein found in staph and developed a lupus-like disease, with kidney disease and autoantibodies like those found in the blood of lupus patients.
The findings are published online this month in The Journal of Immunology. The next step is to study lupus patients to see if the staph protein in question plays a similar role in humans, says co-author Vaidehi Chowdhary, M.D., a Mayo Clinic rheumatologist.
"We think this protein could be an important clue to what may cause or exacerbate lupus in certain genetically predisposed patients," Dr. Chowdhary says. "Our hope is to confirm these findings in lupus patients and hopefully prevent flares."
The cause is often unknown; it appears people genetically predisposed to lupus may develop it when something in the environment triggers it, such as infections, certain drugs or even sunlight.
Physicians do not really know what causes lupus, so the discovery of the staph protein's possible role is exciting, Dr. Chowdhary says.
In the mice studied, a staph protein known as a staphylococcal enterotoxin B, or SEB, activated autoreactive T and B lymphocytes, a type of white blood cells, leading to an inflammatory illness mirroring lupus. Research on people has shown that carrying staph bacteria is linked to autoimmune diseases such as psoriasis, Kawasaki disease and graulomatosis with polyangiitis.