Tag Archives: Marla Paul

Trojan horse nanoparticle for asthma

A brand new technique for dealing with asthma is being proposed by researchers at Northwestern University (US), according to an April 18, 2016 news item on ScienceDaily,

In an entirely new approach to treating asthma and allergies, a biodegradable nanoparticle acts like a Trojan horse, hiding an allergen in a friendly shell, to convince the immune system not to attack it, according to new Northwestern Medicine research. As a result, the allergic reaction in the airways is shut down long- term and an asthma attack prevented.

The technology can be applied to food allergies as well. The nanoparticle is currently being tested in a mouse model of peanut allergy, similar to food allergy in humans.

“The findings represent a novel, safe and effective long-term way to treat and potentially ‘cure’ patients with life-threatening respiratory and food allergies,” said senior author Stephen Miller, the Judy Gugenheim Research Professor of Microbiology-Immunology at Northwestern University Feinberg School of Medicine. “This may eliminate the need for life-long use of medications to treat lung allergy.”

An April 18, 2016 Northwestern University news release (also on EurekAlert) by Marla Paul, which originated the news item, expands on the theme,

It’s the first time this method for creating tolerance in the immune system has been used in allergic diseases. The approach has been used in autoimmune diseases including multiple sclerosis and celiac disease in previous preclinical Northwestern research.

The asthma allergy study was in mice, but the technology is progressing to clinical trials in autoimmune disease. The nanoparticle technology is being developed commercially by Cour Pharmaceuticals Development Co., which is working with Miller to bring this new approach to patients. A clinical trial using the nanoparticles to treat celiac disease is in development.

“It’s a universal treatment,” Miller said. “Depending on what allergy you want to eliminate, you can load up the nanoparticle with ragweed pollen or a peanut protein.”

The nanoparticles are composed of an FDA-approved biopolymer called PLGA that includes lactic acid and glycolic acid.

Also a senior author is Lonnie Shea, adjunct professor of chemical and biological engineering at Northwestern’s McCormick School of Engineering and of obstetrics and gynecology at Feinberg, and chair of biomedical engineering at the University of Michigan.

When the allergen-loaded nanoparticle is injected into the bloodstream of mice, the immune system isn’t concerned with it because it sees the particle as innocuous debris. Then the nanoparticle and its hidden cargo are consumed by a macrophage, essentially a vacuum-cleaner cell.

“The vacuum-cleaner cell presents the allergen or antigen to the immune system in a way that says, ‘No worries, this belongs here,’” Miller said. The immune system then shuts down its attack on the allergen, and the immune system is reset to normal.

The allergen, in this case egg protein, was administered into the lungs of mice who have been pretreated to be allergic to the protein and already had antibodies in their blood against it. So when they were re-exposed to it, they responded with an allergic response like asthma. After being treated with the nanoparticle, they no longer had an allergic response to the allergen.

The approach also has a second benefit. It creates a more normal, balanced immune system by increasing the number of regulatory T cells, immune cells important for recognizing the airway allergens as normal. This method turns off the dangerous Th2 T cell that causes the allergy and expands the good, calming regulatory T cells.

If I understand this rightly, they’re rebalancing the immune system so it doesn’t treat innocuous material (dust, mould, etc.) as an allergen.

Here’s a link to and a citation for the paper,

Biodegradable antigen-associated PLG nanoparticles tolerize Th2-mediated allergic airway inflammation pre- and postsensitization by Charles B. Smarr, Woon Teck Yap, Tobias P. Neef, Ryan M. Pearson, Zoe N. Hunter, Igal Ifergan, Daniel R. Getts, Paul J. Bryce, Lonnie D. Shea, and Stephen D. Miller. PNAS 2016 doi: 10.1073/pnas.1505782113 Published ahead of print April 18, 2016,

This paper is behind a paywall.

Penetrating the skin barrier

Researchers at Northwestern University (Illinois, US) have found a way to deliver gene regulation technology using skin moisturizers. From the July 3, 2012 news item on Science Blog,

A team led by a physician-scientist and a chemist — from the fields of dermatology and nanotechnology — is the first to demonstrate the use of commercial moisturizers to deliver gene regulation technology that has great potential for life-saving therapies for skin cancers.

The topical delivery of gene regulation technology to cells deep in the skin is extremely difficult because of the formidable defenses skin provides for the body. The Northwestern approach takes advantage of drugs consisting of novel spherical arrangements of nucleic acids. These structures, each about 1,000 times smaller than the diameter of a human hair, have the unique ability to recruit and bind to natural proteins that allow them to traverse the skin and enter cells.

Applied directly to the skin, the drug penetrates all of the skin’s layers and can selectively target disease-causing genes while sparing normal genes. Once in cells, the drug simply flips the switch of the troublesome genes to “off.”

The news item originated from a July 2, 2012 news release, by Marla Paul for Northwestern University, which provides more details about the researchers,

“The technology developed by my collaborator Chad Mirkin and his lab is incredibly exciting because it can break through the skin barrier,” said co-senior author Amy S. Paller, M.D., the Walter J. Hamlin Professor, chair of dermatology and professor of pediatrics at Northwestern University Feinberg School of Medicine. She also is director of Northwestern’s Skin Disease Research Center.

A co-senior author of the paper, Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering. He also is the director of Northwestern’s International Institute for Nanotechnology.

Interdisciplinary research is a hallmark of Northwestern. Paller and Mirkin said their work highlights the power of physician-scientists and scientists and engineers from other fields coming together to address a difficult medical problem.

“This all happened because of our world-class presence in both cancer nanotechnology and skin disease research,” Paller said. “In putting together the Skin Disease Research Center proposal, I reached out to Chad to see if his nanostructures might be applied to skin disease. We initially worked together through a pilot project of the center, and now the rest is history.”

As for the work itself, here are more details from Paul’s news release,

The key is the nanostructure’s spherical shape and nucleic acid density. Normal (linear) nucleic acids cannot get into cells, but these spherical nucleic acids can. Small interfering RNA (siRNA) surrounds a gold nanoparticle like a shell; the nucleic acids are highly oriented, densely packed and form a tiny sphere. The RNA’s sequence is programmed to target the disease-causing gene.

“We now can go after a whole new set of diseases,” Mirkin said. “Thanks to the Human Genome Project and all of the genomics research over the last two decades, we have an enormous number of known targets. And we can use the same tool for each, the spherical nucleic acid. We simply change the sequence to match the target gene. That’s the power of gene regulation technology.”

The nanostructures were developed in Mirkin’s lab on the Evanston campus and then combined with a commercial moisturizer. Next, down in Paller’s Chicago lab, the researchers applied the therapeutic ointment to the skin of mice and to human epidermis. The nanostructures were designed to target epidermal growth factor receptor (EGFR), a biomarker associated with a number of cancers.

In both cases, the drug broke through the epidermal layer and penetrated the skin very deeply, with cells taking up 100 percent of the nanostructures. They selectively knocked down the EGFR gene, decreasing the production of the problem proteins.

After a month of continued application of the ointment, there was no evidence of side effects, inappropriate triggering of the immune system or accumulation of the particles in organs. The treatment is skin specific and doesn’t interfere with other cells.

After all the concerns  about nanosunscreens and nanoparticles penetrating the skin raised by civil society groups, the Friends of the Earth in particular, it’s interesting to note that doctors and scientists consider penetration of the skin barrier to be extremely difficult. Of course, they seem to have solved that problem which means the chorus of concerns may rise to new heights.