Featured Research

from universities, journals, and other organizations

St. Jude Develops Vaccine Against Potential Pandemic Influenza Virus H5N1 Using Reverse Genetics

Date:
April 4, 2003
Source:
St. Jude Children's Research Hospital
Summary:
Scientists at St. Jude Children's Research Hospital announced today the development of a vaccine against H5N1, a new lethal influenza virus that triggered the World Health Organization (WHO) to declare a pandemic alert in February 2003.

(MEMPHIS, TENN.--April 2, 2003) Scientists at St. Jude Children's Research Hospital announced today the development of a vaccine against H5N1, a new lethal influenza virus that triggered the World Health Organization (WHO) to declare a pandemic alert in February 2003.

Related Articles


The virus appeared in birds in Hong Kong late last year and subsequently killed one of two infected people with rapidly progressive pneumonia in the past month. St. Jude developed the vaccine in only four weeks from the time it received the H5N1 sample from colleagues in Hong Kong.

The announcement comes at a time when a second, as-yet-unidentified virus, has taken several lives around the world. The unknown virus, which causes severe acute respiratory syndrome (SARS), appears to have originated at the same time and in the same place as the new "flu."

The development of the initial ("seed") batch of H5N1 vaccine is significant because humans do not have a natural immunity to the virus, according to Robert Webster, Ph.D., a member of the Department of Infectious Diseases at St. Jude. Rather, humans appear to become infected through contact with chickens and other birds. In the past the virus killed only the chickens it infected. But the new variant of H5N1 also killed many kinds of wild birds, which is unusual.

If H5N1 acquires the ability to pass from human to human, there would be the potential for concern similar to that for SARS, according to Webster.

"It's likely there were two things that prevented the 1997 poultry influenza outbreak in Hong Kong from becoming more deadly--its inability to spread from human to human and the slaughter of more than 1.5 million chickens and other birds in the open-air markets of Hong Kong, which eliminated the source of the virus," Webster said. "In fact, the sudden appearance of SARS in the same region of the world is just another warning that the large populations of people and poultry in this region are a potential source of viruses."

Webster is the director of the WHO's U.S. Collaborating Center at St. Jude that studies animal influenza viruses. It is the only WHO laboratory that focuses on the transmission of animal viruses to humans.

Webster's laboratory has sent the seed H5N1 vaccine to the Centers for Disease Control in Atlanta and the World Influenza Center in London for further testing, in preparation for initial Phase I and Phase II trials in humans. "It's important to move right along with these trials in case the virus begins spreading from person to person," Webster says. Led by Richard Webby, Ph.D., and Daniel Perez, Ph.D., the St. Jude laboratory team successfully modified a technique called reverse genetics to permit them to develop the H5N1 vaccine so quickly. Using the samples of H5N1 obtained from Hong Kong, Webby mixed two genes from H5N1 with six genes from a second virus (A/PR8/34)[H1N1]). H1N1 is a rapidly growing "master" strain of virus commonly used to make vaccines.

The genes from flu viruses produce proteins called HA and NA, which are on the surface of the virus, in full "view" of the immune system. Webby took the modified gene for HA and the NA from H5N1 and mixed them inside a cell with six genes from H1N1. The HA gene was modified to abolish its ability to cause disease and therefore made it safer to use in the vaccine.

The genes mixed together, and the resulting vaccine virus produced in the cell thus carried HA and NA from H5N1. But because of the alterations to the HA, and the rest of the genes being derived from H1N1, the new virus vaccine cannot cause disease. Rather, it can only stimulate the immune system to respond to H5N1.

"The St. Jude vaccine is like a gun without ammunition," said Elaine Tuomanen, M.D., director of the St. Jude Department of Infectious Diseases. "The vaccine looks deadly enough for its HA and NA proteins to alert the immune system. But in reality, it's carrying blanks that can't cause disease."

Key to the quick success in developing the vaccine was the on-campus availability of GMP (Good Manufacturing Practices) facilities, which are equivalent in quality to those used by pharmaceutical companies to make biological agents such as vaccines. In addition, the centralization of genetic analysis and other molecular biology work, performed in the Hartwell Center for Bioinformatics and Biotechnology at St. Jude, greatly accelerated the process of building the vaccine components.

"We've been lucky twice with H5N1--once in 1997 and once so far during this current outbreak--in not experiencing human-to-human transmission," Webster says. "But the mixing bowl in Hong Kong is still stirring up new variations of familiar viruses. Although we just made a vaccine against one of that mixing bowl's nasty viral brews, SARS shows us there's always another threat down the road."

###

St. Jude Children's Research Hospital St. Jude Children's Research Hospital, in Memphis, Tennessee, was founded by the late entertainer Danny Thomas. The hospital is an internationally recognized biomedical research center dedicated to finding cures for catastrophic diseases of childhood. The hospital's work is supported through funds raised by ALSAC. ALSAC covers all costs not covered by insurance for medical treatment rendered at St. Jude Children's Research Hospital. Families without insurance are never asked to pay. For more information, please visit http://www.stjude.org.


Story Source:

The above story is based on materials provided by St. Jude Children's Research Hospital. Note: Materials may be edited for content and length.


Cite This Page:

St. Jude Children's Research Hospital. "St. Jude Develops Vaccine Against Potential Pandemic Influenza Virus H5N1 Using Reverse Genetics." ScienceDaily. ScienceDaily, 4 April 2003. <www.sciencedaily.com/releases/2003/04/030404072206.htm>.
St. Jude Children's Research Hospital. (2003, April 4). St. Jude Develops Vaccine Against Potential Pandemic Influenza Virus H5N1 Using Reverse Genetics. ScienceDaily. Retrieved October 26, 2014 from www.sciencedaily.com/releases/2003/04/030404072206.htm
St. Jude Children's Research Hospital. "St. Jude Develops Vaccine Against Potential Pandemic Influenza Virus H5N1 Using Reverse Genetics." ScienceDaily. www.sciencedaily.com/releases/2003/04/030404072206.htm (accessed October 26, 2014).

Share This



More Health & Medicine News

Sunday, October 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Texas Nurse Nina Pham Cured of Ebola

Texas Nurse Nina Pham Cured of Ebola

AFP (Oct. 25, 2014) — An American nurse who contracted Ebola while caring for a Liberian patient in Texas has been declared free of the virus and will leave the hospital. Duration: 01:01 Video provided by AFP
Powered by NewsLook.com
Toxin-Packed Stem Cells Used To Kill Cancer

Toxin-Packed Stem Cells Used To Kill Cancer

Newsy (Oct. 25, 2014) — A Harvard University Research Team created genetically engineered stem cells that are able to kill cancer cells, while leaving other cells unharmed. Video provided by Newsy
Powered by NewsLook.com
IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) — IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) — A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
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