Diabetes vaccine test showing promise

PITTSBURGH -- Shannon Roland has a son with Type 1 diabetes who must watch his diet and take six blood-glucose readings and five injections of insulin every day.So she said she'll do anything necessary to prevent her other three sons from developing the disease, which can have a genetic link.That opportunity arose when Children's Hospital of Pittsburgh began a series of Type 1 Diabetes TrialNet studies focused on helping people delay or prevent the onset of Type 1 or reduce complications after onset.Type 1 diabetes is usually diagnosed in children and young adults, and was previously known as juvenile diabetes. In Type 1 diabetes, the body does not produce insulin.For the Rolands, the key study is one testing whether a daily capsule of oral insulin can serve as a vaccine against Type 1 diabetes in people predisposed to the disease. Early trials indicate some success.Insulin must be injected to reduce blood-glucose levels. But the theory holds that oral insulin, when digested, breaks down into proteins that serve to build up regulatory T-cells in the immune system. These help block rogue T-cells from destroying insulin-producing beta cells in the pancreas, causing Type 1.Roland, of Somerset, Pa., said her 9-year-old son, Caleb, has been participating in the oral insulin trials for about a year. Only after the study is complete will they learn whether he is receiving oral insulin or a placebo.But his participation will help determine whether oral insulin can serve as a Type 1 vaccine.To date, Caleb hasn't developed diabetes, despite blood work showing he has the same antibodies as his 8-year-old brother, Jabin, who was diagnosed with diabetes four years ago. Those antibodies indicate the immune system already is attacking the beta cells.But Dr. Dorothy J. Becker, director of Children's Hospital's Division of Endocrinology and Diabetes, said the hospital -- part of a consortium of research institutions conducting TrialNet studies for Type 1 -- needs help in finding people at the right stage of disease development to qualify for the studies.One study involves people diagnosed with Type 1, but in an early enough stage to still produce some natural insulin. The trial is testing whether existing drugs can reduce or halt beta-cell destruction and preserve insulin production, which can make the disease easier to manage with fewer health complications.Children's Hospital has an extensive epidemiological study under way to determine what environmental factors trigger Type 1 diabetes, which is on the rise for inexplicable reasons. The hospital is enrolling those babies before birth or shortly after birth that have a genetic predisposition to Type 1.The hospital also has been following 800 patients with diabetes and their relatives for almost 30 years to determine whether viral infection or escalating obesity is a factor in producing pancreatic or beta cell damage. Results are expected by 2014.Worldwide, TrialNet institutions hope to screen 200,000 people to find hundreds of patients to participate in various studies. Other TrialNet studies in the pipeline could include others not eligible for current studies.Insulin is the hormone that allows blood glucose to enter cells for use as energy. Too little insulin causes blood-glucose levels to build to dangerous and even deadly levels.People with Type 1 must take daily injections of insulin, test blood-sugar levels regularly, eat a healthful diet and exercise to prevent such long-term complications as heart disease, strokes, blindness, kidney disease and circulatory problems leading to limb amputations."If oral insulin works (as a vaccine), we can do genetic screenings of relatives and give oral insulin from the day a baby is born," Becker said.As for the Rolands, Caleb and Jabin's other brothers, Seth, 11, and Zane, 3, show no antibodies indicating an immediate risk of diabetes. But it could develop with age."If we can help in any way possible to find a cure or offset it as long as possible, that's the best thing we can do," Roland said.E-mail David Templeton at dtempleton(at)post-gazette.com(Distributed by Scripps Howard News Service, www.scrippsnews.com.)