Featured Research

from universities, journals, and other organizations

Study Indicates Special Vaccines Could Prevent Insulin-Dependent Diabetes

Date:
February 1, 2001
Source:
University Of North Carolina At Chapel Hill
Summary:
Results of a new University of North Carolina at Chapel Hill medical study suggest that vaccines can be made using plasmid DNA that would inhibit development of insulin-dependent diabetes, a growing health threat in the United States.

Chapel Hill -- Results of a new University of North Carolina at Chapel Hill medical study suggest that vaccines can be made using plasmid DNA that would inhibit development of insulin-dependent diabetes, a growing health threat in the United States.

Plasmid DNA is circular genetic material obtained from bacteria. A chronic inflammatory disease, insulin-dependent diabetes, also called type I or juvenile onset diabetes, results from cells of the body's own immune system going awry and eventually killing other cells needed to produce insulin. In their experiments, UNC-CH researchers succeeded in preventing diabetes from starting in special laboratory mice that develop diabetes as they age. More importantly, the scientists say, they also halted progression of the illness in animals already affected.

" This work is very encouraging because it has the potential to be useful in clinical settings," said Dr. Roland Tisch, assistant professor of microbiology and immunology at the UNC-CH School of Medicine. "In the past, our group and others could manipulate the damaging auto-immune response in various animal models for type I diabetes but not in ways that would be readily feasible clinically."

A report on the research appears in the Feb. 1 issue of the Journal of Immunology. Besides Tisch, authors are Dr. Bo Wang, postdoctoral fellow; Dr. Donald J. Weaver, now a UNC-CH medical student; visiting scholar Dr. Bo Liu, Thi Bui, research assistant; Dr. James Arthos of the National Institutes of Health; and Dr. David V. Serreze, a researcher at Jackson Laboratory in Bar Harbor, Me.

"Recently, a Canadian group in Edmonton showed for the first time that islet beta cells -- the cells in the pancreas that produce insulin -- could be transplanted successfully in people with diabetes," Tisch said. "For more than a year, their patients have been free of insulin injections. A key issue, however, is that those individuals have had to take a cocktail of drugs that suppresses their immune systems, and they might have to continue taking it for the rest of their lives."

Such drugs are needed to prevent patients' immune systems from destroying the transplanted beta cells, the scientist said. But the compounds also could make recipients more susceptible to infectious diseases and cancers and produce other unknown but serious consequences when given over many years.

Tisch's group used genetic vaccines they created to re-establish the natural balance between two kinds of immune cells -- Th1 cells and Th2 cells. When misbehaving, the former attacks the critical insulin-producing islet beta cells, while the latter normally keep the former from doing that. When Th2 cells fail to do their job, Th1 cells eventually lead to type I diabetes.

"Our approach was relatively simple," Tisch said. "The vaccines allowed us to selectively suppress the body's auto-immune response while leaving the remainder of the immune response intact."

He and colleagues engineered their vaccines to express two different proteins -- one that activated T cells that recognize islet beta cells and another that boosted those T cells to develop into Th2 cells needed to hold Th1 cells in check. They then inserted the genes encoding those proteins, respectively named GAD65-IgGFc and IL-4, onto the injectable circular plasmids, which do not themselves produce an immune response.

"One of the appealing features of plasmid DNA vaccines, which in other forms already are being tested clinically against certain infectious diseases such as HIV-1and cancer, is that the DNA persists for long periods," Tisch said. "We gave our mice three injections in three weeks, and the majority of the animals have remained diabetes-free for more than a year. Ideally, human patients might require injection of plasmid DNA vaccines only every year or two."

The continuing research is part of a National Institutes of Health program project grant, co-sponsored by the Juvenile Diabetes Research Foundation, to UNC-CH and headed by Drs. Jenny Ting and Jeffrey A. Frelinger, professor and chair, respectively, of microbiology and immunology.


Story Source:

The above story is based on materials provided by University Of North Carolina At Chapel Hill. Note: Materials may be edited for content and length.


Cite This Page:

University Of North Carolina At Chapel Hill. "Study Indicates Special Vaccines Could Prevent Insulin-Dependent Diabetes." ScienceDaily. ScienceDaily, 1 February 2001. <www.sciencedaily.com/releases/2001/02/010201071629.htm>.
University Of North Carolina At Chapel Hill. (2001, February 1). Study Indicates Special Vaccines Could Prevent Insulin-Dependent Diabetes. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2001/02/010201071629.htm
University Of North Carolina At Chapel Hill. "Study Indicates Special Vaccines Could Prevent Insulin-Dependent Diabetes." ScienceDaily. www.sciencedaily.com/releases/2001/02/010201071629.htm (accessed September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins