New 'bouncer' molecule halts rheumatoid arthritis

Researchers at Northwestern University Feinberg School of Medicine have discovered why the immune cells of people with rheumatoid arthritis become hyperactive and attack the joints and bones. The immune cells have lost their bouncer, the burly protein that keeps them in line the same way a bouncer in a nightclub controls rowdy patrons.

The Feinberg School team has identified this bouncer, a protein called , which prevents immune cells from launching into their destructive rampage through the and bone. When the scientists developed and injected an imitation of the protein into an of rheumatoid arthritis, the disease process was halted.

"The bouncer molecule stopped the immune cells from going crazy," said lead author Harris Perlman, associate professor of at Northwestern's Feinberg School. "Imagine destructive customers in a bar, and the bouncer says, 'You are going to behave!' That's P21. This discovery opens up a new avenue for future therapies, which are greatly needed for rheumatoid arthritis."

Previous research by the Feinberg team showed people with rheumatoid arthritis were low in P21, but the protein's role was unknown. The new study, which will be published in the journal Arthritis & Rheumatism, reveals the protein's vital role in keeping the immune cells in check.

Currently, there is no effective, nontoxic way to stop the hyperactive immune cells, Perlman said.

To develop the new approach, Perlman and his team tested five different parts, called peptides, of P21. He slipped each peptide into a "ghostlike" molecule that he injected into mice with a rheumatoid arthritis-like disease. The molecule secretly infiltrated the immune cells. After the seven-day trial, one of the tested peptides had calmed the overactive immune cells without toxic effects. Next, Perlman plans a 30-day study with the same peptide to monitor efficacy and toxicity over a longer period of time.

Existing treatments for include low-level chemotherapy and steroids. These are not always effective, however, and they are frequently accompanied by side effects. A newer class of therapy, which is sometimes used in combination with chemotherapy and steroids, is biologic response modifiers. These are antibodies or other proteins that reduce the inflammation produced by the hyperactive . These biologics don't work for everyone, though, and can be associated with side effects including the risk of infection.

add to favorites email to friend print save as pdf

Related Stories

New 'suicide' molecule halts rheumatoid arthritis

Jan 28, 2010

A researcher from Northwestern University Feinberg School of Medicine has invented a novel way to halt and even reverse rheumatoid arthritis. He developed an imitation of a suicide molecule that floats undetected into overactive ...

Rheumatoid arthritis breakthrough

Nov 12, 2008

Rheumatoid arthritis is a painful, inflammatory type of arthritis that occurs when the body's immune system attacks itself. A new paper, published in this week's issue of PLoS Biology, reports a breakthrough in the unders ...

Recommended for you

Where Ebola battles are won

37 minutes ago

(HealthDay)—Four hospitals that are home to advanced biocontainment facilities have become America's ground zero in the treatment of Ebola patients.

Depression tied to worse lumbar spine surgery outcomes

3 hours ago

(HealthDay)—Depressive symptoms are associated with poorer long-term outcome in patients undergoing surgery for lumbar spinal stenosis (LSS), according to research published in the Oct. 1 issue of The Sp ...

Ebola death toll edging to 4,900 mark: WHO

3 hours ago

The death toll in the world's worst-ever Ebola outbreak has edged closer to 4,900, while almost 10,000 people have now been infected, new figures from the World Health Organization showed Wednesday.

US to track everyone coming from Ebola nations

3 hours ago

U.S. authorities said Wednesday that everyone traveling into the U.S. from Ebola-stricken nations will be monitored for symptoms for 21 days. That includes returning American aid workers, federal health employees ...

User comments