Tomorrow is Today

Nanoparticle Disguised as a Blood Cell Fights Bacterial Infections

The “nanosponges” work by targeting so-called pore-forming toxins, which kill cells by poking holes in them.

One of the most common classes of protein toxins in nature, pore-forming toxins are secreted by many types of bacteria, including Staphylococcus aureus, of which antibiotic-resistant strains, called MRSA, are endemic in hospitals worldwide and cause tens of thousands of deaths annually. They are also present in many types of animal venom.

There are a range of existing therapies designed to target the molecular structure of pore-forming toxins and disable their cell-killing functions. But they must be customized for different diseases and conditions, and there are over 80 families of these harmful proteins, each with a different structure.

Using the new nanosponge therapy, says Zhang, “we can neutralize every single one, regardless of their molecular structure.” 

Zhang and his colleagues wrapped real red blood cell membranes around biocompatible polymeric nanoparticles. A single red blood cell supplies enough membrane material to produce over 3,000 nanosponges, each around 85 nanometers (a nanometer is a billionth of a meter) in diameter.

Since red blood cells are a primary target of pore-forming toxins, the nanosponges act as decoys once in the bloodstream, absorbing the damaging proteins and neutralizing their toxicity. And because they are so small, the nanosponges will vastly outnumber the real red blood cells in the system, says Zhang. This means they have a much higher chance of interacting with and absorbing toxins, and thus can divert the toxins away from their natural targets.

(via Research Published in Nature Nanotechnology Shows That Biomimetic Nanoparticles Can Absorb Bacterially Produced Toxins | MIT Technology Review)

Genetic Copyrights: You Do Not Own Your Own Genome

On the surface, genetic copyright in just another form of the classic problem: Can we better afford to deal with the pricing that results from strong biomedical patents, or with the lack of innovations that may result from their prohibition?

This is one of the main problems facing the drug industry, which sees the vast majority of new medications developed by companies that, arguably, gouge customers in their most desperate times. We’re often presented with a dichotomy — do we want poor sick people, or dead sick people?

Yet, this study represents a growing movement within biomedical research, one aimed at changing the way we treat biological products. Traditionally, one could patent “anything under the sun that is made by man”, which would seem to exclude biological patents, but American and European patent authorities accept them by the thousands.

(via Do you own your genes, or can Big Pharma patent them? | ExtremeTech)

Carbon Nanotubes Used in Scaffolds to Grow Working Rat Hearts

Heart cells share many of the problems of neurons, from a research perspective; they are woefully inept at directing their own growth through space, requiring virtually every effort be made on their behalf, and even when led to the right place require all sorts of special genetic and chemical allowances. It was once thought impossible to regrow neurons, but lately we’ve come to realize that it’s just very, very finicky. Not the least of the reasons for this is conductivity; neurons cannot work unless they somehow come to meet one another such that an electrical signal can propagate between them. Heart cells are much the same — a cluster of so-called pacemaker cells keeps the whole thing contracting as one. This requires not just that the pacemaker signal pass between the cells, but that it happens fast enough for the heart to act seemingly as one coordinated unit.

In pursuit of this, the heart has a class of myocytes that form Purkinje Fibers, long cords that ferry pacemaker signals at a rate unsurpassed in the body. When a contraction signal leaves the pacemaking cells, its order reaches the furthest cells in the heart at an imperceptibly short time after it reaches the closest ones, and so the heart cells seem to beat as one. This ability is absolutely essential to a working heart, and has proven very difficult for organ transplant researchers to overcome.

Enter carbon nanotubes. As anyone familiar with the little critters will know, their important feature is a combination of strength, flexibility, and conductivity. Some combination of these virtues has made them of import to virtually every advanced research and manufacturing sector, from space elevators to flexible computers. Now, we must add conductive tissue development to that quickly growing list. By laying the conductive carbon nanotubes coated with a growth medium, researchers were able to create a scaffold that mimicked the utility of the Purkinje Fibers. By coating the scaffold in rat cardiomyocytes, they were able to create a colony of heart cells capable of contracting properly.

(via Carbon nanotubes make it possible to grow human hearts | ExtremeTech)

Gene Therapy Cures Diabetes in Dogs in SIngle Treatment

Five lucky diabetic beagles have been cured of their canine type 1 diabetes using gene therapy, according to research published in the February issue of Diabetes.

Researchers from Barcelona’s Universitat Autonoma previously found the therapy effective in treating mice, but this is the first time gene therapy — when a patient’s DNA is supplemented or changed to treat a disease — has proven successful in curing diabetes in large animals.

Gene therapy encodes a functional gene to replace a mutated one, or inserts DNA that produces a therapeutic protein to treat a disease. In this case, the dogs were injected with two extra genes that together form a “glucose sensor” that can regulate glucose uptake and reduce excessive glucose levels in the blood.

Four years later, the dogs that received both genes had no symptoms of diabetes and stabilized glucose levels. They recovered a normal body weight and didn’t exhibit any secondary complications.

(via Gene Therapy Cures Diabetic Dogs In Only One Shot | Popular Science)

Scientists Perform Logic Functions Using DNA Within Living Cells

By modifying a genetic toggle switch, synthetic biologists at MIT have found a way to perform logic functions inside of living cells.

Based on plasmids, circular strings of DNA, scientists devised and inserted 16 different DNA strings into Escherichia coli cells, one for  each of the binary logic functions allowable in computation.

“The key to the system is the use of recombinase enzymes, which cut and rearrange promoter and terminator DNA sequences to turn them on or off. In other words, recombinase enzymes are the inputs that determine whether the output gene is transcribed.”

(via Scientists Turn Cells into Living Computers | IdeaFeed | Big Think)

Researchers Embed Light-Emitting Probe into Single Living Cancer Cell, Successfully Track it for Eight Days

This nanoprobe could be an important breakthrough for photonic cancer therapy. The researchers suggest that it could be used to develop patient-specific cancer therapies, where an individual’s treatment could be tailored to their own genetic needs.

The probe can be used to detect specific proteins within the cell, and could be developed to sense DNA or RNA. When coated in molecules or antibodies that attract the desired protein, any of that protein within a cell will cling to the nanobeam like iron to a magnet, causing a shift in the wavelength of light it emits. This could be used in drug testing to see immediately if a drug is producing or inhibiting a certain protein.

“Devices like the photonic cavities we have built are quite possibly the most diverse and customizable ingredients in photonics,” senior author Jelena Vuckovic explained. “Applications span from fundamental physics to nanolasers and biosensors that could have profound impact on biological research.”

(via Scientists Insert A Light-Emitting Bioprobe Into A Living Cell | Popular Science)

How Neuroscience Will Fight Five Age-Old Afflictions

New Electronic and viral treatments for seizures, dementia, blindness, paralysis and deafness.

(via How Neuroscience Will Fight Five Age-Old Afflictions | Popular Science)

Controlled Evolution Used to Grow Artificial Enzymes With Targeted Properties, May Be More Effective Than Design

Enzymes created in laboratories typically follow principles of rational enzyme design, in which researchers develop a preconceived idea of what an enzyme should be, model it on a computer, and then influence its development to produce the molecule that they want.

By contrast, this new enzyme, developed by Burckhard Seelig’s lab at UM’s College of Biological Sciences, was developed in the same way enzymes evolve in nature. A large quantity of candidate proteins were placed together in culture and screened with every successive generation for their ability to perform a desired function (in this case, joining two pieces of RNA together). Unlike rational enzyme design, this approach isn’t limited by what the researchers know about enzyme structure. All the researchers really need to know is what they want from the enzyme. Evolution finds the best way to get there.

(via Controlled Evolution In A Test Tube Produces Artificial Enzymes | Popular Science)

Progress Shown in Trial of Viral Therapy for Cancer

Over the weekend, Nature Medicine described… promising results [from] a somewhat different approach to ensuring that the virus leads to the death of cancer cells: if the virus doesn’t kill the cells directly, it revs up the immune system to attack them.

…The basic idea is to leverage decades of work on some common viruses. This research has identified a variety of mutations [that keep] viruses from growing in normal cells. It means that if you inject the virus into a healthy individual, it won’t be able to infect any of their cells.

But cancer cells are different, as they carry a series of mutations of their own. In some cases, these mutations compensate for the problems in the virus. To give one example, the p53 protein normally induces aberrant cells to undergo an orderly death called apoptosis. It also helps shut down the growth of viruses in a cell, which is why some viruses encode a protein that inhibits p53. Cancer cells tend to damage or eliminate their copies of p53 so that it doesn’t cause them to undergo apoptosis.

So imagine a virus with its p53 inhibitor deleted. It can’t grow in normal cells since they have p53 around, but it can grow in cancer cells, which have eliminated their p53. The net result should be a cancer-killing virus.

…In the new trial, the virus in question takes a similar approach. The virus, vaccinia (a relative of smallpox used for vaccines), carries a gene that is essential for it to make copies of itself. Researchers have engineered a version without that gene, ensuring it can’t grow in normal cells (which have their equivalent of the gene shut down). Cancer cells need to reactivate the gene, meaning they present a hospitable environment for the mutant virus.

The researchers added another trick by inserting a gene for a molecule that helps recruit immune cells (granulocyte-macrophage colony-stimulating factor, or GM-CSF)… By adding GM-CSF, the virus should help bring immune cells to the site of the cancer and activate them, creating a more aggressive immune response to any cells that survive viral infection.

(via Latest trial of a virus engineered to kill cancer shows promise | Ars Technica)

Engineers Use Magnetic Levitation to Assemble Lung Tissue From Cells

Engineers at Nano3D Biosciences recently showcased a new technology in which they magnetically levitate four kinds of cells and assemble them into realistic lung tissue. Not only do they not mind if you use their techniques for yourself, they have made aMad Scientist kit available free of charge to any serious user, and offered hard cash incentives for the most innovative use of their product. Entry into the brave new world of biohacking just got a whole lot easier.

(via Assembling living tissue with 3D maglev tech: A biohacker’s dream come true | ExtremeTech)