Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Researchers create new 'smart' nanocapsule delivery system for use in protein therapy

Abstract:
Shell of single-protein capsule degrades or remains intact based on environment

Researchers create new 'smart' nanocapsule delivery system for use in protein therapy

Los Angeles, CA | Posted on December 21st, 2009

Protein therapy the delivery of healthy proteins directly into human cells to replace malfunctioning proteins is considered one of the most direct and safe approaches for treating diseases. But its effectiveness has been limited by low delivery efficiency and the poor stability of proteins, which are frequently broken down and digested by cells' protease enzymes before they reach their intended target.

In what could signal a major advance in protein therapeutics, researchers at the UCLA Henry Samueli School of Engineering and Applied Science have developed a new intracellular delivery platform that uses nanocapsules made up of a single-protein core with a thin polymer shell that can be engineered to either degrade or remain stable based on the cellular environment.

Their research appears Dec. 29 in the January 2010 edition of the journal Nature Nanotechnology and is currently available online.

"For proteins in general, it's very difficult to cross the cell membrane. The protease will usually digest it, making stability an issue," said lead study author Yunfeng Lu, a UCLA professor of chemical and biomolecular engineering. "Here, we've been able to use this new technology to stabilize the protein, making it very easy to cross the cell membrane, allowing the protein to function properly once inside the cell. This is one of our biggest achievements."

Nanocapsules are submicroscopic containers composed of an oily or aqueous core in this case a single protein surrounded by a thin, permeable polymer membrane roughly several to tens of nanometers thick. The membranes of the nanocapsules used in the new UCLA delivery method can degrade or remain intact depending on the size of the molecular substrates with which their embedded protein must interact.

Non-degradable nanocapsules are more stable, and small molecular substrates can readily diffuse to the protein embedded inside. The capsule's non-degradable skin meanwhile protects the cargo from protease attacks and stabilizes the protein from other factors, like varying temperatures and pH levels.

However, a non-degradable skin may also prevent substrates of larger molecular weight from reaching the embedded protein. In order for the protein to be able to interact with a large substrate, a degradable skin can also be used.

When the protein nanocapsule is taken in by the cell, it will stay within the endosome initially. Endosomes generally have lower pH levels than the outside cellular environment; the lower pH triggers the degradation of the polymer skin layer, releasing the protein cargo intracellularly.

The research team, led by study co-author Yi Tang, a UCLA professor of chemical and biomolecular engineering, has also demonstrated that such skin layers can also be degraded by incorporating components that are sensitive to proteases. This approach will also allow for a more targeted delivery of the proteins.

The new study has shown that multiple proteins can now be delivered to cells with high efficiency and activity but low toxicity, allowing for potential applications in protein therapies, vaccines, cellular imaging, tumor tracking, cancer therapies and even cosmetics.

"Covering the protein payload with a polymeric shell provides added stability in circulation, where there are plenty of proteases to degrade the naked protein," said Lily Wu, professor of medical and molecular pharmacology at the David Geffen School of Medicine at UCLA and an author of the study. "This will clearly be advantageous in improving efficacy of delivery.

"Further, the ability to deliver cargo intracellularly and to control the release of the protein cargo by pH or other environmental parameters is very important," she said. "Improving safety, efficiency and targeted delivery of protein payload is the holy grail of modern medicine. This new technology holds promise in all these aspects and that's why it is so exciting to me."

"Right now, a lot of protein therapeutics available only act outside of the cell because it's been difficult to deliver the proteins inside the cell," said Tatiana Segura, a UCLA professor of chemical and biomolecular engineering and a study co-author.

The team hopes the new technology will serve as a delivery platform for any type of protein or protein drug. Though the study, when originally submitted, described the use of the technology with five different proteins, in the short time since, the team has expanded to more than two dozen different proteins.

"I think the important next step is to apply this technology in a relevant, preclinical disease model," Wu said. "Based on the promising results of improved efficiency of delivery into cells, I anticipate improved efficacy in preclinical animal models as well.

"In the long run, the hope is to develop new technology that can make a difference in the lives of patients," she said. "I feel extremely fortunate to be able to collaborate with this elite group of chemical engineers on this exciting project."

Zhen Liu, a professor of chemical engineering at Tsinghua University in China, is also a team member and co-author.

The study was funded in part by the Defense Threat Reduction Agency (DTRA), NSF-CAREER, Sandia National Laboratories and the CheungKong Scholar Program through China's Tsinghua University.

The UCLA Engineering team would especially like to thank Ilya Elashvili of DTRA for his support.

####

About UCLA Henry Samueli School of Engineering and Applied Science
The UCLA Henry Samueli School of Engineering and Applied Science, established in 1945, offers 28 academic and professional degree programs, including an interdepartmental graduate degree program in biomedical engineering. Ranked among the top 10 engineering schools at public universities nationwide, the school is home to seven multimillion-dollar interdisciplinary research centers in wireless sensor systems, nanotechnology, nanomanufacturing and nanoelectronics, all funded by federal and private agencies.

For more information, please click here

Contacts:
Media Contacts
Wileen Wong Kromhout,
(310) 206-0540

Copyright © UCLA

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Quantum physics just got less complicated December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Universality of charge order in cuprate superconductors: Charge order has been established in another class of cuprate superconductors, highlighting the importance of the phenomenon as a general property of these high-Tc materials December 22nd, 2014

Govt.-Legislation/Regulation/Funding/Policy

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

ORNL microscopy pencils patterns in polymers at the nanoscale December 17th, 2014

Nanomedicine

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Creation of 'Rocker' protein opens way for new smart molecules in medicine, other fields December 18th, 2014

Iranian Researchers Produce Electrical Pieces Usable in Human Body December 18th, 2014

Zenosense, Inc. - Hospital Collaboration - 400 Person Lung Cancer Detection Trial December 17th, 2014

Announcements

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Quantum physics just got less complicated December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Universality of charge order in cuprate superconductors: Charge order has been established in another class of cuprate superconductors, highlighting the importance of the phenomenon as a general property of these high-Tc materials December 22nd, 2014

Nanobiotechnology

Scientists trace nanoparticles from plants to caterpillars: Rice University study examines how nanoparticles behave in food chain December 16th, 2014

FEI and Oregon Health & Science University Install a Complete Correlative Microscopy Workflow in Newly Built Collaborative Science Facility December 16th, 2014

UCLA engineers first to detect and measure individual DNA molecules using smartphone microscope December 15th, 2014

Biomimetic dew harvesters: Understanding how a desert beetle harvests water from dew could improve drinking water collection in dew condensers December 8th, 2014

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE