Back home   |   Bookmark   |   Start page   |   Site map    
Services
News
Channels
Home & Family
Leisure
Technology
Business
Science
Site Search
Free email




Viral spheres could help deliver a new class of vaccines

Theaalineed.com
(NC&T/SU) "We want to make proteins that are important as pharmaceuticals and for other uses," said Swartz, a professor of chemical engineering and of bioengineering, during an interview before the ACS meeting. "If we could produce them with great efficiency and at very low cost, that would be an important step."

He emphasized: "A living cell has many unique demands for energy, such as for the synthesis of many types of molecules. We would like to focus all of those metabolic resources just on making our product."

Whole cells can be difficult for researchers to use for making custom proteins because they don't always tolerate the chemical changes a researcher needs to impose to make a specific product. Cell-free techniques, in contrast, can be more robust because they use just the protein-making machinery of cells. To harvest just the parts he needs, Swartz literally rips cells open by applying intense shear forces.

For one of his more recent contributions to developing cell-free techniques, Swartz received the Gaden Award at the ACS meeting. The award is named for Elmer L. Gaden, the founding editor of the journal Biotechnology & Bioengineering, and recognizes the most outstanding paper of the year in that journal. Swartz, who holds the Leland T. Edwards Professorship in the School of Engineering at Stanford, received the award for a paper showing for the first time how glucose, the abundant sugar produced by photosynthesis and used in many organisms, can be used to power cell-free protein synthesis.

James Swartz. (Photo: Stanford U.)
"We are delighted to honor Professor Swartz with the Gaden Award this year," said journal editor Douglas S. Clark, a chemical engineering professor at the University of California-Berkeley. "His paper has been recognized by all of the editors for its originality and likely impact."

At the ACS session where Swartz received the award he also presented one of the most recent innovations in his lab, the cell-free production of engineered viral capsids. The capsids are based on the outer shell of a naturally occurring virus that infects E. coli bacteria. They are formed when 180 copies of the same protein assemble into a nanoscale soccer ball.

"We think these little spheres, 27 nanometers in diameter, will form the basis for a new class of pharmaceuticals and a new class of materials," Swartz said. "For example, to date we've been seriously limited in our ability to both produce and to modify capsids to turn them into effective vaccines."

But now researchers in Swartz's lab, principally doctoral student Brad Bundy, who is supported by a Stanford Graduate Fellowship, not only have produced capsids cell-free for the first time but also have attached amino acids to the capsid surfaces. The amino acids allow the capsids to either stick to and carry specific proteins or stick to other capsids, allowing their assembly en masse. The tiny spheres could therefore transport targeted vaccines or medicines around the bloodstream or could be linked together in different configurations to make novel materials. Materials from assembled capsids could be light, strong and biodegradable, Swartz said.

Piggybacking vaccines on capsids may provide safer and more effective vaccinations than current methods, Swartz said. Most vaccines today work by introducing dead or weakened copies of viruses, mixed with other chemicals, into the bloodstream with the hope that they will provoke a strong, albeit general, response by the immune system. The process is akin to advertising a product to a random audience and hoping some consumers become interested.

With an engineered capsid, in contrast, a vaccine maker could attach a very specific protein designed to stimulate only the appropriate immune-system cells. A vaccine with these well-targeted capsids would be more likely than a traditional vaccine to elicit a strong and specific response. The capsid method is akin to advertising a product directly to the people who are most likely to want it.

About the Author
©2006 All rights reserved

More articles
Mystery of genetics
Biodegradable wipe
Fast-freeze snapshot
Molecular motor structural
Individual cells in 3d
Gravitational force
Mixture of genomic sequences
Manipulate birth order
Adult barnacles
Viral spheres
Silk of the tarantulas
Climate hot for insects
Parasitic plants sniff out hosts
Chilly bugs
Inusual island evolution
Cell membranes function
Two melanopsin genes
Immune system avoids
Food pathogens
Plant's circadian rhythm
Quotes
I will not expose the ignorance of the faculty. - Bart Simpson.

I want an Internet. Can I have one of those? -- Spice Girl Mel B.,aka Scary Spice, pointing to a monitor during an AOL press conference

I want to get a tatoo of myself on my entire body, only 2 taller. -- Steven Wright

I think you should defend to the death their right to march, and then go down and meet them with baseball bats.-Woody Allen, on the KKK


Writers
If you are a writer and want to see your article published at Theallineed.com, just click here to submit.

Info
Today...
In the news...
Nepal's human rights commission has made great strides, says UN official
Congratulating Nepal's National Human Rights Commission (NHRC) on its 8th anniversary, a United Nations official today said that the South Asian body has significant progress in the past year.
Which Operating System do you use?
Windows
Linux
OS2
FreeBSD
Other
 
Things to ponder
There comes a time when you should stop expecting other people to make a big deal about your birthday. That time is age eleven.

Did you know...
Rats multiply so quickly that in 18 months, two rats could have over a million descendants.

Quote of the day
A fact is a simple statement that everyone believes. It is innocent, unless found guilty. A hypothesis is a novel suggestion that no one wants to believe. It is guilty, until found effective.
Edward Teller

Featured article
The Rocks: Sydney's outdoor museum
The Rocks is Sydney's oldest area and is steeped in history and character. One reason is the strict control on development has limited the construction of brash modern buildings.

 
© 2002 - 2007 Lexur