Corporate Banner
Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Putting the Squeeze on Cells

Published: Wednesday, January 23, 2013
Last Updated: Wednesday, January 23, 2013
Bookmark and Share
By deforming cells, researchers can deliver RNA, proteins and nanoparticles for many applications.

Living cells are surrounded by a membrane that tightly regulates what gets in and out of the cell. This barrier is necessary for cells to control their internal environment, but it makes it more difficult for scientists to deliver large molecules such as nanoparticles for imaging, or proteins that can reprogram them into pluripotent stem cells.

Researchers from MIT have now found a safe and efficient way to get large molecules through the cell membrane, by squeezing the cells through a narrow constriction that opens up tiny, temporary holes in the membrane. Any large molecules floating outside the cell — such as RNA, proteins or nanoparticles — can slide through the membrane during this disruption.

Using this technique, the researchers were able to deliver reprogramming proteins and generate induced pluripotent stem cells with a success rate 10 to 100 times better than any existing method. They also used it to deliver nanoparticles, including carbon nanotubes and quantum dots, which can be used to image cells and monitor what’s happening inside them.

“It’s very useful to be able to get large molecules into cells. We thought it might be interesting if you could have a relatively simple system that could deliver many different compounds,” says Klavs Jensen, the Warren K. Lewis Professor of Chemical Engineering, professor of materials science and engineering, and a senior author of a paper describing the new device in this week’s issue of the Proceedings of the National Academy of Sciences.

Robert Langer, the David H. Koch Institute Professor at MIT, is also a senior author of the paper. Lead authors are chemical engineering graduate student Armon Sharei, Koch Institute research scientist Janet Zoldan, and chemical engineering research associate Andrea Adamo.

A general approach

Biologists have previously developed several ways to get large molecules into cells, but all of them have drawbacks. DNA or RNA can be packaged into viruses, which are adept at entering cells, but that approach carries the risk that some of the viral DNA will get integrated into the host cell. This method is commonly used in lab experiments but has not been approved by the FDA for use in human patients.

Another way to sneak large molecules into a cell is to tag them with a short protein that can penetrate the cell membrane and drag the larger cargo along with it. Alternatively, DNA or proteins can be packaged into synthetic nanoparticles that can enter cells. However, these systems often need to be re-engineered depending on the type of cell and material being delivered. Also, with some nanoparticles much of the material ends up trapped in protective sacs called endosomes inside the cell, and there can be potential toxic side effects.

Electroporation, which involves giving cells a jolt of electricity that opens up the cell membrane, is a more general approach but can be damaging to both cells and the material being delivered.

The new MIT system appears to work for many cell types — so far, the researchers have successfully tested it with more than a dozen types, including both human and mouse cells. It also works in cells taken directly from human patients, which are usually much more difficult to manipulate than human cell lines grown specifically for lab research.

The new device builds on previous work by Jensen and Langer’s labs, in which they used microinjection to force large molecules into cells as they flowed through a microfluidic device. This wasn’t as fast as the researchers would have liked, but during these studies, they discovered that when a cell is squeezed through a narrow tube, small holes open in the cell membrane, allowing nearby molecules to diffuse into the cell.

To take advantage of that, the researchers built rectangular microfluidic chips, about the size of a quarter, with 40 to 70 parallel channels. Cells are suspended in a solution with the material to be delivered and flowed through the channel at high speed — about one meter per second. Halfway through the channel, the cells pass through a constriction about 30 to 80 percent smaller than the cells’ diameter. The cells don’t suffer any irreparable damage, and they maintain their normal functions after the treatment.

Special delivery

The research team is now further pursuing stem cell manipulation, which holds promise for treating a wide range of diseases. They have already shown that they can transform human fibroblast cells into pluripotent stem cells, and now plan to start working on delivering the proteins needed to differentiate stem cells into specialized tissues.

Another promising application is delivering quantum dots — nanoparticles made of semiconducting metals that fluoresce. These dots hold promise for labeling individual proteins or other molecules inside cells, but scientists have had trouble getting them through the cell membrane without getting trapped in endosomes.

In a paper published in November, working with MIT graduate student Jungmin Lee and chemistry professor Moungi Bawendi, the researchers showed that they could get quantum dots inside human cells grown in the lab, without the particles becoming confined in endosomes or clumping together. They are now working on getting the dots to tag specific proteins inside the cells.

The researchers are also exploring the possibility of using the new system for vaccination. In theory, scientists could remove immune cells from a patient, run them through the microfluidic device and expose them to a viral protein, and then put them back in the patient. Once inside, the cells could provoke an immune response that would confer immunity against the target viral protein.

The research was funded by the National Institutes of Health and the National Cancer Institute.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,900+ scientific posters on ePosters
  • More Than 5,300+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

New Method for Analyzing Crystal Structure
Exotic materials called photonic crystals reveal their internal characteristics with new method.
Monday, November 28, 2016
Biomarker Guiding Cancer Therapy
Biologists link levels of Mena protein to breast cancer cells’ sensitivity to chemotherapy.
Tuesday, November 22, 2016
Capsule Achieves Long-Term Drug Delivery
Novel drug delivery method could aid in elimination of malaria and treatment of many other diseases.
Monday, November 21, 2016
Synthetic Cells Isolate Genetic Circuits
Encapsulating molecular components in artificial membranes offers more flexibility in designing circuits.
Tuesday, November 15, 2016
Turning Greenhouse Gas into Gasoline
New catalyst provides design principles for producing fuels from carbon dioxide emissions.
Tuesday, November 15, 2016
New Approach Against Salmonella
Researchers have developed a strategy to immunize against microbes that invade the gastrointestinal tract, including Salmonella.
Tuesday, November 08, 2016
Laser Particles Could Provide Sharper Tissue Images
New imaging technique stimulates particles to emit laser light, could create higher-resolution images.
Tuesday, November 08, 2016
Engineers Design New Weapon Against Bacteria
Researchers have successfully engineered antimicrobial peptides that can kill bacterial strains resistant to existing antibiotics.
Thursday, November 03, 2016
Predicting Cancer Cells’ Response to Chemotherapy
Researcher develop method for testing cell ability to perform different types of DNA repair, which can reveal tumors’ sensitivity to drugs.
Wednesday, November 02, 2016
Nanobionic Spinach Detects Dangerous Chemicals
Scientists have changed spinach plants into biosensors that can detect harful chemicals and wirelessly relay the information.
Tuesday, November 01, 2016
Fighting Cancer with the Power of Immunity
Researchers at MIT have used a combination of four different therapies to activate both of the immune system’s two branches, producing a coordinated attack that led to the complete disappearance of large, aggressive tumors in mice.
Friday, October 28, 2016
Fighting Cancer with Immune Response
New treatment elicits two-pronged immune response that destroys tumors in mice.
Tuesday, October 25, 2016
MRIs for Fetal Health
Algorithm could help analyze fetal scans to determine whether interventions are warranted.
Monday, October 24, 2016
Mapping Serotonin in the Living Brain
Imaging technique that creates a 3D video of serotonin transport could aid antidepressant development.
Monday, October 24, 2016
Achieving “Green” Desalination
Workshop explores ways to reduce or eliminate the carbon footprint of seawater desalination plants.
Thursday, October 20, 2016
Scientific News
Big Genetics in BC: The American Society for Human Genetics 2016 Meeting
Themes at this year's meeting ranged from the verification, validation, and sharing of data, to the translation of laboratory findings into actionable clinical results.
Stem Cells in Drug Discovery
Potential Source of Unlimited Human Test Cells, but Roadblocks Remain.
Cancer Genetics: Key to Diagnosis, Therapy
When applied judiciously, cancer genetics directs caregivers to the right drug at the right time, while sparing patients of unnecessary or harmful treatments.
BGI Sequences Gingko Tree, Revealing Large, Highly Repetitive Genome
Researchers at BGI have sequenced the more than 10-gigabase ginkgo genome to find a high number of repetitive sequences as well as a number of gene clusters that appear to be involved in defense mechanisms.
Survey of New York City Soil Uncovers Medicine-Making Microbes
Microbes have long been an invaluable source of new drugs. And to find more, we may have to look no further than the ground beneath our feet.
Accelerating the Detection of Foodborne Bacterial Outbreaks
The speed of diagnosis of foodborne bacterial outbreaks could be improved by a new technique developed by researchers at the Georgia Institute of Technology.
Making Personalized Medicine a Reality
Groundbreaking technique developed at McMaster University is helping to pave the way for advances in personalized medicine.
Scientists Identify Unique Genomic Features in Testicular Cancer
The findings may shed light on factors in other cancers that influence their sensitivity to chemotherapy.
Top 10 Life Science Innovations of 2016
2016 has seen the release of some truly innovative products. To help you digest these developments, The Scientist have listed their top picks for the year.
BioCision Forms MedCision
The new company will focus on technologies for the management and automation of vital clinical processes.
Scroll Up
Scroll Down
Skyscraper Banner

SELECTBIO Market Reports
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,900+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
5,300+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!