New Research Uncovers Why Many With Lupus Are Resistant to Traditional Treatments

Findings Could Lead to Lower Doses of Medication for Lupus Patients, Reducing Serious Side Effects

DALLAS, July 12 /PRNewswire-USNewswire/ -- Two immune system proteins could be the culprit behind many lupus patients' resistance to widely used steroid treatments, scientists with the Baylor Research Institute (BRI) in Dallas announced today. It is estimated that more than 5 million people suffer from lupus worldwide.

Currently, those with lupus and other autoimmune diseases, commonly treat the condition with corticosteroids to suppress their overactive immune system and prevent it from attacking healthy tissues which can result in symptoms such as inflammation, pain and organ damage.

These steroid treatments work by killing certain immune system cells, including plasmacytoid dendritic cells (PDCs) that overproduce type 1 interferons, an immune system substance that contributes to lupus and other autoimmune diseases. However, unlike other conditions, steroid treatments are not as effective against these cells in those with lupus.

By largely studying children with systemic lupus erythematosus (SLE), BRI scientists in collaboration with scientists at Dynavax in Berkeley, CA, were able to solve the mystery behind the resistance. They determined that two immune system proteins known as toll-receptor 7 (TLR7) and toll-receptor 9 (TLR9), cause an activation of PDCs—the very cells steroids target—negating the effects of treatment. BRI scientists reported their findings in the June issue of the journal Nature.

"We have long known that these receptors played a critical role in lupus, but until now, we didn't know they were directly interfering with the effects of steroid treatments," says Virginia Pascual, M.D., one of the principal investigators of the study and a researcher at Baylor Institute for Immunology Research, a component of BRI. "By blocking TLR7 and TLR9 function, we may have found a safer way to treat this debilitating disease."

Currently, large doses of corticosteroids are required to treat lupus, but can cause serious damage to the organs and create other side effects such as weight gain, cataracts, hypertension, brittle bones and thin skin. In children, corticosteroids can also cause stunted growth. In addition, patients must take other strong immunosuppressants which can leave them vulnerable to infections.

"The ultimate goal is to reduce the amount of steroids these patients take because they carry a risk of serious side effects. Our work suggests that if we can somehow block these proteins from carrying out their mission, steroid treatments will be more effective and we may be able to significantly lower the doses," explains Dr. Pascual.

While Dr. Pascual's research focused mainly on children, she says there is no reason to believe these findings would not be true for adults with lupus as well.

"There are limited treatment options for this disease and the ones that do exist are very hard on the body. It is a complicated condition that is difficult to treat so there is an urgent need for this type of research," says Michael Ramsay, M.D., president of BRI. "Not only have Dr. Pascual and her team made a huge contribution to medical research, but they have given hope to the millions of people who suffer from lupus."

Dr. Ramsay adds that blocking agents for TLR7 and TLR9 are already in development and could be ready for clinical studies soon.

Funding for this study was provided by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the Department of Health and Human Services' National Institutes of Health (NIH); the Alliance for Lupus Research, the Mary Kirkland Center for Lupus Research and a Small Business Innovation Research Grant.

About Lupus

Systemic lupus erythematosus (SLE) is an autoimmune disease which occurs when the body's immune system begins attacking healthy tissues. As a result, those with the disease often experience inflammation which causes swelling, pain and tissue damage throughout the body and in severe cases, serious organ damage. The exact cause is unknown, but it is thought to be largely genetic. Lupus primarily affects young women with a peak occurrence between the ages of 15-40. According to the Lupus Foundation of America, more than five million people suffer from lupus worldwide.

About Dynavax Technologies

Dynavax Technologies Corporation, a clinical-stage biopharmaceutical company, discovers and develops novel products to prevent and treat infectious diseases. For more information, visit www.dynavax.com.

About Baylor Research Institute

Baylor Research Institute (BRI) is a leading research center focused on bringing clinical research findings from the laboratory and making them accessible to patient populations of all types. This concept of "bench-to-bedside" makes the patient the top priority as BRI works to understand the origin of a disease, identify potential treatments or preventative therapies and enroll patients in research trials. With more than 900 active research projects by 300 investigators in 20 medical specialties, the institute is nationally and internationally recognized for developing therapies that advance the care and well-being of our community through basic science, translational research, continuity across therapeutic areas and clinical trials.

As part of Dallas-based Baylor Health Care System, and supported by leading clinicians and world-class scientists, BRI specializes in several key areas including: immunology and its clinical indications (such as cancer), auto-immune diseases, rheumatology, and dermatology as well as transplantation, metabolic diseases, cardiovascular disease, infectious diseases and oncology. Research in these areas is bringing the latest discoveries from the laboratory to patient populations across the country and around the world.

For more information about Baylor Research Institute, please visit www.BaylorHealth.edu/Research/.

SOURCE Baylor Research Institute