New Research from Penn Engineering and MIT Shows How Nanoparticles Can Turn Off Genes in Bone Marrow

Michael Mitchell
Michael Mitchell, PhD

by Evan Lerner

Using specialized nanoparticles, researchers from Penn Engineering and the Massachusetts Institute of Technology (MIT) have developed a way to turn off specific genes in cells of bone marrow, which play an important role in producing blood cells. These particles could be tailored to help treat heart disease or to boost the yield of stem cells in patients who need stem cell transplants.

This type of genetic therapy, known as RNA interference, is usually difficult to target to organs other than the liver, where nanoparticles would tend to accumulate. The researchers were able to modify their particles in such a way that they would accumulate in the cells found in the bone marrow.

In a recent Nature Biomedical Engineering study, conducted in mice, the researchers showed that they could use this approach to improve recovery after a heart attack by inhibiting the release of bone marrow blood cells that promote inflammation and contribute to heart disease.

“If we can get these particles to hit other organs of interest, there could be a broader range of disease applications to explore, and one that we were really interested in in this paper was the bone marrow. The bone marrow is a site for hematopoiesis of blood cells, and these give rise to a whole lineage of cells that contribute to various types of diseases,” says Michael Mitchell, Skirkanich Assistant Professor of Innovation in Penn Engineering’s Department of Bioengineering, one of the lead authors of the study.

Marvin Krohn-Grimberghe, a cardiologist at the Freiburg University Heart Center in Germany, and Maximilian Schloss, a research fellow at Massachusetts General Hospital (MGH), are also lead authors on the paper, which appears today in Nature Biomedical Engineering. The paper’s senior authors are Daniel Anderson, a professor of Chemical Engineering at MIT and a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science, and Matthias Nahrendorf, a professor of Radiology at MGH.

Mitchell’s expertise is in the design of nanoparticles and other drug delivery vehicles, engineering them to cross biological barriers that normally block foreign agents. In 2018, he received the NIH Director’s New Innovator Award to support research on delivering therapeutics to bone marrow, a key component of this new study.

The researchers have shown they can deliver nanoparticles to the bone marrow, influencing their function with RNA silencing. At top right, the bone marrow is not yet treated with particles that turn off a gene called SDF1. At bottom right, the number of neutrophils (blue) decreases, indicating that they have been released from bone marrow after treatment. At left, treatment with a control nanoparticle does not affect the number of neutrophils before and after treatment.

Read the full story at Penn Engineering Today.

In Memoriam: David Geselowitz, 1930-2020

David Geselowitz

Penn Engineering mourns the death of our former colleague Dr. David Geselowitz, who died on August 22, 2020. The Penn Engineering and Penn State communities have lost a brilliant scientist and researcher, and an extraordinary teacher, mentor and friend.

Dr. Geselowitz was born in Philadelphia in 1930, and graduated from the University of Pennsylvania, where he received his bachelor’s, master’s and doctoral degrees in Electrical Engineering in 1951, 1954 and 1958, respectively. As the top student in his undergraduate class, he received the Atwater Kent Award.

After receiving his Ph.D., he joined the faculty of the University of Pennsylvania and subsequently founded Penn’s doctoral program in biomedical engineering. In 1971, he moved to Penn State University to implement a graduate program in bioengineering.

Dr. Geselowitz was known for his contributions to the theory of the electrocardiogram (EKG) and the development of the artificial heart. As noted by the late Dr. Herman Schwan, “David was the best man I had met in electrocardiography work. The National Academy of Engineering recognized him for that work. He became a leader in the country in the field.”

For more on the life of Dr. Geselowitz, please see the tribute from his longtime colleagues at Penn State: https://news.engr.psu.edu/2020/geselowitz-david-obituary.aspx

This story originally appeared in Penn Engineering News.

A potential cause of CAR T side effects, and a path forward

Single cell sequencing aided researchers in identifying a previously undiscovered molecule in the brain.

Chimeric antigen receptor (CAR) T cell therapy has revolutionized treatment of leukemia, lymphoma, and multiple myeloma. But some people who have received this treatment experience neurotoxicity, or damage to the brain or nervous system.

New research from a team led by Avery Posey, an assistant professor of systems pharmacology and translational therapeutics in the Perelman School of Medicine, provides evidence that this side effect may owe to a molecule in the brain that scientists previously didn’t know was there.

The work, published in the journal Cell, revealed that the protein CD19 is present in brain cells that protect the blood-brain barrier. Prior to the finding, scientists believed CD19 was only expressed on B cells, and the protein served as a target for certain forms of CAR-T therapy. The discovery may chart a path forward for new strategies to effectively treat cancer while sparing the brain.

“The next question is,” says Posey, “can we identify a better target for eliminating B cell related malignancies other than CD19, or can we engineer around this brain cell expression of CD19 and build a CAR T cell that makes decisions based on the type of cell it encounters—for instance, CAR T cells that kill the B cells they encounter, but spare the CD19 positive brain cells?”

Read more at Penn Medicine News. Avery Posey is a member of the Department of Bioengineering Graduate Group.

César de la Fuente on AIChE’s 35 Under 35 List

César de la Fuente, PhD

César de la Fuente, Presidential Assistant Professor in Psychiatry, Microbiology, and Bioengineering, was named one of the American Institute of Chemical Engineers’ (AIChE) 35 members under 35 for 2020.

“The AIChE 35 Under 35 Award was founded to recognize young chemical engineers who have achieved greatness in their fields,” reads the 2020 award announcement. “The winners are a group of driven, engaged, and socially active professionals, representing the breadth and diversity that chemical engineering exemplifies.”

De la Fuente was named in the list’s “Bioengineering” category for his his lab’s work in machine biology. Their goal is to develop computer-made tools and medicines that will combat antibiotic resistance. De la Fuente has already been featured on several other young innovators lists, including MIT Technology Review’s 35 under 35 and GEN’s Top 10 under 40, both in 2019. His research in antibiotic resistance has been profiled in Penn Today and Penn Engineering Today, and he was recently awarded Penn Health-Tech’s inaugural NEMO Prize for his proposal to develop paper-based COVID diagnostic system that could capture viral particles on a person’s breath.

In addition to being named on the 2020 list, the honorees will receive a $500 prize and will be celebrated at the 2020 AIChE Annual Meeting this November.

Learn more about de la Fuente’s pioneering research on his lab website.

‘The Self-Organized Movement to Create an Inclusive Computational Neuroscience School’

When the COVID-19 pandemic began taking hold in the United States, one of the first “superspreader” events was an academic conference. Such conferences have long been a primary way for researchers to share new findings and launch collaborations, but with thousands of people from around the world, indoors and in close proximity, it quickly became clear that the traditional format for these events would need to radically change.

Konrad Kording
Konrad Kording

Konrad Kording, a Penn Integrates Knowledge Professor with appointments in the departments of Bioengineering and Computer and Information Science in Penn Engineering and the Department of Neuroscience at Penn’s Perelman School of Medicine, was ahead of the curve on this shift. With the issues of prohibitive costs and environmental impact of travel in mind, Kording had already started brainstorming ways of reinventing the traditional conference format when the pandemic made it a necessity.

The resulting event, Neuromatch, involved algorithmically analyzing participants’ work in order to connect researchers who might not otherwise meet. Building on the success of that “unconference,” Kording and his colleagues launched the Neuromatch Academy, a free-ranging online summer school organized around the same principles.

Ashley Juavinett writing for The Simons Collaboration on the Global Brain, recently dug into how Neuromatch was able to pull together 1,750 students from 70 countries in a matter of months:

Kording already had experience quickly pulling together online events. Early in the pandemic, together with Dan Goodman, Titipat Achakulvisut and Brad Wyble, he developed an online ‘unconference,’ which featured both lectures and a virtual networking component designed to mimic the in-person interactions that make conferences so valuable. (For more, see “Designing a Virtual Neuroscience Conference.”) Soon after, they decided to spin that success into a full-fledged summer school offering live lectures with top computational neuroscientists, guided coding exercises to teach mathematical approaches to neural modeling and analysis, and community support from mentors and teaching assistants (TAs).

The result was a summer school with well-designed content, a diverse student body, including participants from U.S.-sanctioned Iran, and a determined group of organizers who managed to pull off the most inclusive computational neuroscience school yet. NMA now has its eye on a future with even broader representation across countries, languages and skill levels. This year has been incredibly difficult for many, but NMA has provided an important precedent for how to collaborate across, and even dismantle, all sorts of barriers.

Continue reading “The Self-Organized Movement to Create an Inclusive Computational Neuroscience School” at The Simons Collaboration on the Global Brain.

Originally posted on the SEAS blog. Media contact Evan Lerner.

Avery Posey’s cancer research takes high risks for big rewards

by Melissa Moody

Avery Posey, PhD (Image: Penn Medicine Newsby Melissa Moody

Much of the world, including research at Penn Medicine, has focused its attention on how T cells–which play a central role in immune response—might shape the trajectory of COVID-19 infection, and how immunotherapy can shed light on treatment of the disease.

Already a leader in immunotherapy research and treatment, Penn Medicine pioneered the groundbreaking development of CAR T cell cancer therapy. Avery Posey, an assistant professor of systems pharmacology and translational therapeutics, trained as a postdoctoral fellow in the lab of Carl June, who pioneered CAR T cell immunotherapy to treat cancer. Now as a faculty member at Penn, Posey has maintained a focus on T cell therapeutics, mostly for the treatment of cancer.

“This research combines two of my biggest interests—the use of gene therapy to treat disease and the investigation of little known biology, such as the roles of glycans in cell behavior. The pursuit of new knowledge, the roads less traveled—those are my inspirations,” Posey says.

Read more at Penn Medicine News.

N.B.: Avery Posey and Carl June are members of the Department of Bioengineering Graduate Group. Learn more about BE’s Grad Group Faculty here.

Penn Bioengineering’s Tsourkas Lab and Penn Start-up AlphaThera Awarded $667,000 SBIR Phase II Grant to Improve COVID-19 Detection Assays

To combat the COVID-19 pandemic caused by the SARS-CoV2 virus, Dr. Andrew Tsourkas’s Targeted Imaging Therapeutics and Nanomedicine (Titan) Lab in Penn Bioengineering, in collaboration with the Penn-based startup, AlphaThera, was recently awarded a $667,000 SBIR Phase II Grant Extension to support its efforts in commercializing COVID-19 detection technology. The grant supports work to address the growing need for anti-viral antibody testing. Specifically, the Tsourkas Lab and AlphaThera hope to leverage their expertise with antibody conjugation technologies to reduce the steps and complexity of existing detection assays to enable greater production and higher sensitivity tests. AlphaThera was founded in 2016 by Andrew Tsourkas, PhD, Professor of Bioengineering and James Hui, MD, PhD, a graduate of the Perelman School of Medicine and Penn Bioengineering’s doctoral program.

During this pandemic it is crucial to characterize disease prevalence among populations, understand immunity, test vaccine efficacy and monitor disease resurgence. Projections have indicated that millions of daily tests will be needed to effectively control the virus spread. One important testing method is the serological assay: These tests detect the presence of SARS-CoV2 antibodies in a person’s blood produced by the body’s immune system responding to infection. Serological tests not only diagnose active infections, but also establish prior infection in an individual, which can greatly aid in forecasting disease spread and contact tracing. To perform the serological assays for antibody detection, well-established immunoassay methods are used such as ELISA.

A variety of issues have slowed the distribution of these serological assays for antibody testing. The surge in demand for testing has caused shortages in materials and reagents that are crucial for the assays. Furthermore, complexity in some of the assay formats can slow both production and affect the sensitivity of test results. Recognizing these problems, AlphaThera is leveraging its novel conjugation technology to greatly improve upon traditional assay formats.

With AlphaThera’s conjugation technology, the orientation of antibodies can be precisely controlled so that they are aligned and uniformly immobilized on assay detection plates. This is crucial as traditional serological assays often bind antibodies to plates in a non-uniform manner, which increases variability of results and reduces sensitivity. See Fig 1 below. With AlphaThera’s uniform antibody immobilization, assay specificity could increase by as much as 1000- fold for detection of a patient’s SaRS-CoV2 antibodies.

Fig 1: Uniform vs Non-Uniform Immobilized Antibodies on Surface: Top is AlphaThera improvement, showing how antibodies would be uniformly immobilized and oriented on a plate for detection. Bottom is how many traditional serological assays immobilize antibodies, resulting in variability of results and lower specificity.

Furthermore, AlphaThera is addressing the shortage of assay reagents, specifically secondary antibody reagents, by removing certain steps from traditional serological assays. Rather than relying on secondary antibodies for detection of the patient antibodies, AlphaThera’s technology can label the patient SaRS-CoV2 primary antibodies directly in serum with a detection reagent. This eliminates several processing steps, reducing the time of the assay by as much as 50%, as well as the costs.

The Tsourkas Lab and AlphaThera have initiated their COVID-19 project, expanding into the Pennovation Center and onboarding new lab staff. Other antibody labeling products have also become available and are currently being prepared for commercialization. Check out the AlphaThera website to learn more about their technology at https://www.alphathera.com.

NIH SBIR Phase II Grant Extension— 5-R44-EB023750-03 (PI: Yu)  — 10/07/2020 – 10/07/2021

Jennifer Phillips-Cremins Wins CZI Grant to Study 3D Genome’s Role in Neurodegenerative Disease

The Chan Zuckerberg Initiative’s Collaborative Pairs Pilot Project Award is part of its Neurodegeneration Challenge Network

Jennifer Phillips-Cremins, Ph.D.

Read the full story on the Penn Engineering blog.

Danielle Bassett on ‘A Radical New Model of the Brain’

In a ‘Wired’ feature, Bassett helps explain the growing field of network neuroscience and how the form and function of the brain are connected.

Danielle Bassett, Ph.D.

Early attempts to understand how the brain works included the pseudoscience of phrenology, which theorized that various mental functions could be determined through the shape of the skull. While those theories have long been debunked, modern neuroscience has shown a kernel of truth to them: those functions are highly localized to different regions of the brain.

Now, Danielle Bassett, Professor of J. Peter Skirkanich Professor of Bioengineering and Electrical and Systems Engineering, is pioneering a new subfield that goes even deeper into the connection between the brain’s form and function: network neuroscience.

In a recent feature article in Wired, Bassett explains the concepts behind this new subfield. While prior understanding has long relied on the idea that certain areas of the brain control certain functions, Bassett and other network neuroscientists are using advances in imaging and machine learning to reveal the role the connections between those areas play.

For Bassett, one of the first indicators that these connections mattered more than previously realized was the shape of the neurons themselves.

Speaking with Wired’s Grace Huckins, Bassett says:

“Neurons are not spherical — neurons have a cell body, and then they have this long tail that allows them to connect to many other cells. You can even look at the morphology of the neuron and say, ‘Oh, well, connectivity has to matter. Otherwise, it wouldn’t look like this.’”

Read more about Bassett and the field of network neuroscience in Wired.

Originally posted on the Penn Engineering blog.

‘For Neurodegeneration, a Different Way to Slice the Pie’

Danielle Bassett, Ph.D.

Danielle Bassett, J. Peter Skirkanich Professor in the departments of Bioengineering and Electrical and Systems Engineering, has been called the “doyenne of network neuroscience.” The burgeoning field applies insights from the field of network science, which studies how the structure of networks relate to their performance, to the billions of neuronal connections that make up the brain.

Much of Basset’s research draws on mathematical and engineering principles to better understand how mental traits arise, but also applies them more broadly to other challenges in neuroscience.

In her latest paper, “Defining and predicting transdiagnostic categories of neurodegenerative disease,” published in the journal Nature Biomedical Engineering, Bassett collaborated with the Perelman School of Medicine’s Virginia Man-Yee Lee and John Trojanowski to provide a new perspective on the misfolded proteins associated with those diseases.

The researchers used machine learning techniques to create a new classification system for neurodegenerative diseases, one which may redraw the boundaries between them and help explain clinical differences in patients who received the same diagnoses.

BioWorld’s Anette Breindl spoke with Bassett about the team’s findings.

Now, investigators have developed a new approach to classifying neurodegenerative disorders that used the overall patterns of protein aggregation, rather than specific proteins, to define six clusters of patients that crossed traditional diagnostic categories.

“We find that perhaps the way that clinicians have been diagnosing these disorders… is not necessarily the way these disorders work,” Danielle Bassett told BioWorld. “The way we’ve been trying to carve nature at joints is not the way that nature has joints. The joints are elsewhere.”

Continue reading Breindl’s article, “For neurodegeneration, a different way to slice the pie,” at BioWorld.

Originally posted on the Penn Engineering blog. Media contact Evan Lerner.