Featured Research

from universities, journals, and other organizations

Researchers Overcome Hurdle Of Transporting Large Amounts Of DNA To The Nucleus Using Nonviral Vectors

Date:
September 2, 1999
Source:
University Of Pennsylvania Medical Center
Summary:
Viral vectors are currently considered the "gold standard" in gene therapy, albeit expensive ones to produce. In an effort to make a safe and effective, yet inexpensive, gene therapy, bioengineers from the Institute for Medicine and Engineering at the University of Pennsylvania have successfully used nonviral vectors to enhance the process of gene transfer.

Viral vectors are currently considered the "gold standard" in gene therapy, albeit expensive ones to produce. In an effort to make a safe and effective, yet inexpensive, gene therapy, bioengineers from the Institute for Medicine and Engineering at the University of Pennsylvania have successfully used nonviral vectors to enhance the process of gene transfer. They increased the expression of marker DNA in cardiovascular cells by 60 times over previous attempts with nonviral vectors. Using a novel design, the researchers combined a short genetic tag from a nuclear protein with the standard marker gene, which provided the molecular key to the nucleus. They report their findings in the September issue of Nature Biotechnology.

"We're looking for nonviral routes to introduce DNA to cells that are not rapidly dividing," says senior author Scott Diamond, PhD, associate professor of chemical engineering at Penn. "Most gene therapies involve adenoviruses or adeno-associated viruses, but they're expensive to make."

Diamond likens gene transfer to getting over a series of hurdles. First DNA must be transported to the cell surface, then it must be taken up by the cell and packaged into endosomes, then the DNA must escape from the endosomes and be carried to the nucleus. "It's the next hurdle of transporting the DNA into the nucleus that we've essentially catalyzed," says Diamond.

His approach is to deliver DNA using lipoplexes, a lipid complexed to plasmid DNA, a simple, circular form of the genetic material. Specifically, they delivered a reporter gene that codes for an enzyme called beta galactosidase -- along with the nuclear targeting sequence for a riboprotein normally found in the nucleus -- to endothelial cells. "Utilization of plasmid DNA by these cells has been inefficient, until now," says Diamond. "We've achieved a 63-fold increase in the expression of beta galactosidase with the addition of the nuclear protein sequence versus using the plasmid DNA alone. Eighty percent of the cells made beta galactosidase." The 38-amino-acid-long nuclear targeting sequence binds to another protein called transportin, which ferries the entire plasmid DNA to the nuclear pore, where it then enters the nucleus.

What's more, the researchers used nondividing cells because they wanted to mimic the state of most cells in the body, including endothelial cells. These cells are attractive to use because they line blood vessels, so would be a convenient target for an injected gene therapy.

"It's a big jump from what we've done in the culture dish to treating a patient," notes Diamond. "But the nuclear import step is a very important hurdle that's been overcome. We've found a way to get a lot more genetic material expressed, especially considering we were using nondividing cells." This gene transfer enhancement may eventually lead to viral-and lipid-free transfection of nondividing cells such as those found in the body. "Our ultimate goal would be a low cost injectible gene therapy."


Story Source:

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


Cite This Page:

University Of Pennsylvania Medical Center. "Researchers Overcome Hurdle Of Transporting Large Amounts Of DNA To The Nucleus Using Nonviral Vectors." ScienceDaily. ScienceDaily, 2 September 1999. <www.sciencedaily.com/releases/1999/09/990902080046.htm>.
University Of Pennsylvania Medical Center. (1999, September 2). Researchers Overcome Hurdle Of Transporting Large Amounts Of DNA To The Nucleus Using Nonviral Vectors. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/1999/09/990902080046.htm
University Of Pennsylvania Medical Center. "Researchers Overcome Hurdle Of Transporting Large Amounts Of DNA To The Nucleus Using Nonviral Vectors." ScienceDaily. www.sciencedaily.com/releases/1999/09/990902080046.htm (accessed July 26, 2014).

Share This




More Health & Medicine News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. 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