Featured Research

from universities, journals, and other organizations

UT Southwestern Researchers Develop Vaccine Against Deadly Bioterrorism Toxin Ricin

Date:
September 9, 2002
Source:
University Of Texas Southwestern Medical Center At Dallas
Summary:
UT Southwestern Medical Center at Dallas researchers have developed a vaccine in mice against the deadly toxin ricin. Ricin has been used as a biological weapon in many parts of the world.

DALLAS – Sept. 4, 2002 – UT Southwestern Medical Center at Dallas researchers have developed a vaccine in mice against the deadly toxin ricin. Ricin has been used as a biological weapon in many parts of the world.

Related Articles


"Ricin is not only dangerous, but it is also cheap and easy to make," said Dr. Ellen Vitetta, director of the Cancer Immunobiology Center at UT Southwestern and senior author of the study to be published in the Sept. 10 issue of the journal Vaccine.

Large stockpiles of ricin have been found in several countries in the Middle East, Vitetta said. It is a protein produced by castor beans. A single ricin molecule inside a cell shuts down protein synthesis, killing the cell. Ricin can be administered in foods and water or sprayed as an aerosol. A small dose can produce flulike symptoms and result in death in a few days.

Because of its ease of production and high toxicity, ricin has found its way into the arsenals of extremist individuals, groups and governments. Iraq is known to have ricin as part of its biological weapons program, and it is believed that at least one group linked to the terrorist organization al-Qaeda also has experimented with the poison as a weapon. Domestically, several individuals have been arrested and convicted of ricin possession in recent years under the 1989 Biological Weapons Antiterrorism Act.

In creating the new vaccine, UT Southwestern researchers, led by Vitetta, mutated the DNA encoding the active A chain of the toxin. They took out the site that inhibits protein synthesis, as well as the site responsible for inducing vascular leak. The latter was identified by Vitetta's group several years ago in its ongoing efforts to produce safer immunotoxins containing the A chain. Immunotoxins are anti-cancer drugs that have been used by Vitetta and her colleagues in more than 200 cancer patients. The new recombinant A chain induces a protective immune response in mice and protects them against very high doses of ricin. There were no vaccine-related side effects.

The UT Southwestern scientists created three recombinant versions of ricin A chain, two of which were effective as vaccines in mice. Vitetta said E. coli bacteria are used to produce the recombinant DNA, making vaccine production cheap and safe. The researchers believe one or both of the vaccines would be safe and effective in humans.

Vitetta said tests against airborne ricin will be initiated as soon as the experiments can be safely done in a biosafety level 3 facility, which is currently in the planning stage.

Once immunized mice have been subjected to an aerosol challenge, the next step would be to optimize production, formulation and storage of the vaccine. Then 10 human volunteers would be vaccinated. Their sera would be injected into mice and tested for its ability to protect mice from ricin aerosols.

Vitetta said a large government agency, such as the Army or National Institutes of Health, or a well-funded private company would then have to step in and take the vaccine through clinical trials. Such trials are well beyond our resources, she said.

"We have only tested it against injected ricin, but, based on past experience, there's every reason to believe it will be protective against aerosolized ricin," Vitetta said.

Ricin was used in the 1978 murder of Georgi Markov, a Bulgarian author and dissident. Markov, who had defected nine years earlier, was assassinated while waiting for a bus in London when he took an apparently accidental poke from another man's umbrella. Four days later Markov was dead, and it was only upon autopsy that ricin poisoning was revealed as the cause. The lethal dose, estimated at 450 micrograms, was delivered in a pinhead-sized hollow pellet, discovered during the autopsy.

The Centers for Disease Control and Prevention ranks ricin on its "B" list of biowarfare or bioterrorist agents – placing it in the category of a moderate threat.

Other contributors to the Vaccine study, all from the Cancer Immunobiology Center, were first author Dr. Joan E. Smallshaw, postdoctoral researcher; research assistants Ana Firan, John R. Fulmer, Stephen L. Ruback; and Dr. Victor Ghetie, professor.

The work was supported by a National Institutes of Health grant.


Story Source:

The above story is based on materials provided by University Of Texas Southwestern Medical Center At Dallas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas Southwestern Medical Center At Dallas. "UT Southwestern Researchers Develop Vaccine Against Deadly Bioterrorism Toxin Ricin." ScienceDaily. ScienceDaily, 9 September 2002. <www.sciencedaily.com/releases/2002/09/020909065008.htm>.
University Of Texas Southwestern Medical Center At Dallas. (2002, September 9). UT Southwestern Researchers Develop Vaccine Against Deadly Bioterrorism Toxin Ricin. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2002/09/020909065008.htm
University Of Texas Southwestern Medical Center At Dallas. "UT Southwestern Researchers Develop Vaccine Against Deadly Bioterrorism Toxin Ricin." ScienceDaily. www.sciencedaily.com/releases/2002/09/020909065008.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com
Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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