Updated

A Saint Louis University researcher is studying whether a group of immune system cells that is capable of preventing rheumatoid arthritis also can be used to treat the disease.

Richard DiPaolo is assistant professor in the department of molecular microbiology and immunology at Saint Louis University.

He's received a $75,000 grant from the Arthritis National Research Foundation to explore whether the immune system's "regulatory T cells" can effectively treat rheumatoid arthritis.

About 1.3 million Americans have the painful and chronic health problem, an autoimmune disease.

The T cells control inflammation and prevent the development of various autoimmune diseases. But it's not yet certain whether they can stop a disease once it's begun.