Featured Research

from universities, journals, and other organizations

Discovery points to new approach to fight dengue virus

Date:
April 11, 2013
Source:
Purdue University
Summary:
Researchers have discovered that rising temperature induces key changes in the dengue virus when it enters its human host, and the findings represent a new approach for designing vaccines against the aggressive mosquito-borne pathogen.

Purdue researchers Pavel Plevka (left), Ju Sheng and Xinzheng Zhang, stand near the Titan electron microscope in Purdue's Wayne T. and Mary T. Hockmeyer Hall of Structural Biology. In research led by Michael G. Rossmann, Hanley Distinguished Professor of Biological Sciences, the team has discovered that rising temperature induces key changes in the dengue virus when it enters its human host. The findings represent a new approach for designing vaccines against the aggressive mosquito-borne pathogen.
Credit: Purdue University photo/Mark Simons

Researchers have discovered that rising temperature induces key changes in the dengue virus when it enters its human host, and the findings represent a new approach for designing vaccines against the aggressive mosquito-borne pathogen.

The researchers found that the dengue virus particles swell slightly and take on a bumpy appearance when heated to human body temperature, exposing "epitopes," or regions where antibodies could attach to neutralize the virus.

The discovery is significant because it could help to explain why vaccines against dengue have been ineffective, said Michael G. Rossmann, Hanley Distinguished Professor of Biological Sciences at Purdue University.

Scientists have been designing vaccines targeting the virus's smooth appearance found at the cooler temperatures of mosquitoes and ticks.

"The bumpy form of the virus would be the form present in humans, so the optimal dengue virus vaccines should induce antibodies that preferentially recognize epitopes exposed in that form," Rossmann said.

The findings are detailed in a research paper appearing online this week in Proceedings of the National Academy of Sciences.

The researchers used a technique called cryo-electron microscopy to see the three-dimensional structure of the virus at temperatures ranging from 28-37 degrees Celsius (37 degrees Celsius is 98.6 degrees Fahrenheit, or human body temperature). Findings showed that the virus has a smooth appearance while at the cooler temperatures found in mosquito or tick vectors, but then it morphs into the bumpy form at warmer temperatures before fusing to the host cell and delivering its genetic material.

"These findings were a big surprise," said Richard J. Kuhn, professor and head of Purdue's Department of Biological Sciences and director of the Bindley Bioscience Center. "No one expected to see the virus change its appearance as it moves from the mosquito to humans."

The paper was co-authored by postdoctoral researcher Xinzheng Zhang; lab manager Ju Sheng; postdoctoral researcher Pavel Plevka; Kuhn; Michael S. Diamond, a researcher at Washington University School of Medicine; and Rossmann.

Findings also could apply to related infections in the flavivirus family, which includes a number of dangerous insect-borne diseases such as West Nile, yellow fever, tick-borne encephalitis and Japanese encephalitis.

Dengue (pronounced DEN-gē) is a leading cause of serious illness and death among children in some Asian and Latin American countries, causing 50 million to 100 million infections per year. Globally, dengue has grown dramatically in recent decades, placing about half the world's population at risk of infection.

The researchers determined that the bumpy form of the virus is more efficient at infecting mammalian cells. The team was able to measure the virus's infectivity using a laboratory procedure where cells are infected in a culture dish. The bumpy shape is an intermediate stage before the virus becomes unstable, releasing its genetic material. The virus is made of subunit molecules that separate when the virus particle expands into its bumpy form, revealing exposed membrane surfaces between the subunits where antibodies might bind.

The work is funded by the National Institutes of Health and Purdue through university support for a structural biology electron microscope facility.


Story Source:

The above story is based on materials provided by Purdue University. The original article was written by Emil Venere. Note: Materials may be edited for content and length.


Journal Reference:

  1. X. Zhang, J. Sheng, P. Plevka, R. J. Kuhn, M. S. Diamond, M. G. Rossmann. Dengue structure differs at the temperatures of its human and mosquito hosts. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1304300110

Cite This Page:

Purdue University. "Discovery points to new approach to fight dengue virus." ScienceDaily. ScienceDaily, 11 April 2013. <www.sciencedaily.com/releases/2013/04/130411194924.htm>.
Purdue University. (2013, April 11). Discovery points to new approach to fight dengue virus. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2013/04/130411194924.htm
Purdue University. "Discovery points to new approach to fight dengue virus." ScienceDaily. www.sciencedaily.com/releases/2013/04/130411194924.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