Like space shuttles using booster rockets to breach the atmosphere, lipid nanoparticles (LNPs) equipped with the new molecule more successfully deliver medicinal payloads. (Love Employee via Getty Images)
Inspired by the design of space shuttles, Penn Engineering researchers have invented a new way to synthesize a key component of lipid nanoparticles (LNPs), the revolutionary delivery vehicle for mRNA treatments including the Pfizer-BioNTech and Moderna COVID-19 vaccines, simplifying the manufacture of LNPs while boosting their efficacy at delivering mRNA to cells for medicinal purposes.
In a paper in Nature Communications, Michael J. Mitchell, Associate Professor in the Department of Bioengineering, describes a new way to synthesize ionizable lipidoids, key chemical components of LNPs that help protect and deliver medicinal payloads. For this paper, Mitchell and his co-authors tested delivery of an mRNA drug for treating obesity and gene-editing tools for treating genetic disease.
Previous experiments have shown that lipidoids with branched tails perform better at delivering mRNA to cells, but the methods for creating these molecules are time- and cost-intensive. “We offer a novel construction strategy for rapid and cost-efficient synthesis of these lipidoids,” says Xuexiang Han, a postdoctoral student in the Mitchell Lab and the paper’s co-first author.
(From left to right) Breakthrough Prize recipients Drew Weissman, Virginia M-Y Lee, Katalin Karikó, and Carl June at a reception on Feb. 13. (Image: Courtesy of Penn Medicine News)
In popular culture, scientific discovery is often portrayed in “Eureka!” moments of sudden realization: a lightbulb moment, coming sometimes by accident. But in real life—and in Penn Medicine’s rich history as a scientific innovator for more than 250 years—scientific breakthroughs can never truly be distilled down to a single, “ah-ha” moment. They’re the result of years of hard work, perseverance, and determination to keep going, despite repeated, often discouraging, barriers and setbacks.
“Research is [like taking], four, or six, or eight steps back, and then a little stumble forward,” said Drew Weissman, MD, PhD, the Roberts Family Professor of Vaccine Research. “You keep doing that over and over and somehow, rarely, you can get to the top of the step.”
For Weissman and his research partner, Katalin Karikó, PhD, an adjunct professor of Neurosurgery, that persistence—documented in thousands of news stories across the globe—led to the mRNA technology that enabled two lifesaving COVID-19 vaccines, earning the duo numerous accolades, including the highest scientific honor, the 2023 Nobel Prize in Medicine.
Weissman and Karikó were also the 2022 recipients of the Breakthrough Prize in Life Sciences, the world’s largest science awards, popularly known as the “Oscars of Science.” Founded in 2012 by a group of web and tech luminaries including Google co-founder Sergey Brin and Meta CEO Mark Zuckerberg, the Breakthrough Prizes recognize “the world’s top scientists working in the fundamental sciences—the disciplines that ask the biggest questions and find the deepest explanations.” With six total winners, including four from the Perelman School of Medicine (PSOM), Penn stands alongside Harvard and MIT as the institutions whose researchers have been honored with the most Breakthrough Prizes.
Virginia M.–Y. Lee, PhD, the John H. Ware 3rd Professor in Alzheimer’s Research, was awarded the Prize in 2020 for discovering how different forms of misfolded proteins can move from cell to cell and lead to neurodegenerative disease progression. Carl June, MD, the Richard W. Vague Professor in Immunotherapy, is the most recent recipient and will be recognized at a star-studded red-carpet event in April for pioneering the development of CAR T cell therapy, which programs patients’ own immune cells to fight their cancer.
The four PSOM Breakthrough Prize recipients were honored on Tuesday, Feb. 13, 2024, when a new large-scale installation was unveiled in the lobby of the Biomedical Research Building to celebrate each laurate and their life-changing discoveries. During a light-hearted panel discussion, the honorees shared how a clear purpose, dogged determination, and a good sense of humor enabled their momentum forward.
Weissman presented the Department of Bioengineering’s 2022 Herman P. Schwan Distinguished Lecture: “Nucleoside-modified mRNA-LNP therapeutics.” Read more stories featuring Weissman in the BE Blog here.
In the human body, the lungs and their vasculature can be likened to a building with an intricate plumbing system. The lungs’ blood vessels are the pipes essential for transporting blood and nutrients for oxygen delivery and carbon dioxide removal. Much like how pipes can get rusty or clogged, disrupting normal water flow, damage from respiratory viruses, like SARS-CoV-2 or influenza, can interfere with this “plumbing system.”
In a recent study, researchers looked at the critical role of vascular endothelial cells in lung repair. Their work, published in Science Translational Medicine, was led by Andrew Vaughan of the University of Pennsylvania’s School of Veterinary Medicine and shows that, by using techniques that deliver vascular endothelial growth factor alpha (VEGFA) via lipid nanoparticles (LNPs), that they were able to greatly enhance modes of repair for these damaged blood vessels, much like how plumbers patch sections of broken pipes and add new ones.
“While our lab and others have previously shown that endothelial cells are among the unsung heroes in repairing the lungs after viral infections like the flu, this tells us more about the story and sheds light on the molecular mechanisms at play,” says Vaughan, assistant professor of biomedical sciences at Penn Vet. “Here we’ve identified and isolated pathways involved in repairing this tissue, delivered mRNA to endothelial cells, and consequently observed enhanced recovery of the damaged tissue. These findings hint at a more efficient way to promote lung recovery after diseases like COVID-19.”
They found VEGFA’s involvement in this recovery, while building on work in which they used single cell RNA sequencing to identify transforming growth factor beta receptor 2 (TGFBR2) as a major signaling pathway. The researchers saw that when TGFBR2 was missing it stopped the activation of VEGFA. This lack of signal made the blood vessel cells less able to multiply and renew themselves, which is vital for the exchange of oxygen and carbon dioxide in the tiny air sacs of the lungs.
“We’d known there was a link between these two pathways, but this motivated us to see if delivering VEGFA mRNA into endothelial cells could improve lung recovery after disease-related injury,” says first author Gan Zhao, a postdoctoral researcher in the Vaughan Lab.
“LNPs have been great for vaccine delivery and have proven incredibly effective delivery vehicles for genetic information. But the challenge here was to get the LNPs into the bloodstream without them heading to the liver, which is where they tend to congregate as its porous structure lends favor to substances passing from the blood into hepatic cells for filtration,” says Mitchell, an associate professor of bioengineering at Penn Engineering and a coauthor of the paper. “So, we had to devise a way to specifically target the endothelial cells in the lungs.”
Lulu Xue, a postdoctoral researcher in the Mitchell Lab and a co-first author of the paper, explains that they engineered the LNP to have an affinity for lung endothelial cells, this is known as extra hepatic delivery, going beyond the liver.
3d illustration of a damaged and disintegrating cancer cell. (Image: iStock/vitanovski)
The development of any type of second cancer following CAR T cell therapy is a rare occurrence, as found in an analysis of more than 400 patients treated at Penn Medicine, researchers from the Perelman School of Medicine at the University of Pennsylvania reported today in Nature Medicine. The team also described a single case of an incidental T cell lymphoma that did not express the CAR gene and was found in the lymph node of a patient who developed a secondary lung tumor following CAR T cell therapy.
CAR T cell therapy, a personalized form of immunotherapy in which each patient’s T cells are modified to target and kill their cancer cells, was pioneered at Penn. More than 30,000 patients with blood cancers in the United States—many of whom had few, if any, remaining treatment options available—have been treated with CAR T cell therapy since the first such therapy was approved in 2017. Some of the earliest patients treated in clinical trials have gone on to experience long-lasting remissions of a decade or more.
Secondary cancers, including T cell lymphomas, are a known, rare risk of several types of cancer treatment, including chemotherapy, radiation, and stem cell transplant. CAR T cell therapy is currently only approved to treat blood cancers that have relapsed or stopped responding to treatment, so patients who receive CAR T cell therapies have already received multiple other types of treatment and are facing dire prognoses.
In November 2023, the FDA announced an investigation into several reported cases of secondary T cell malignancies, including CAR-positive lymphoma, in patients who previously received CAR T cell therapy products. In January 2024, the FDA began requiring drugmakers to add a safety label warning to CAR T cell products. While the FDA review is still ongoing, it remains unclear whether the secondary T cell malignancies were caused by CAR T cell therapy.
As a leader in CAR T cell therapy, Penn has longstanding, clearly established protocols to monitor each patient both during and after treatment – including follow-up for 15 years after infusion – and participates in national reporting requirements and databases that track outcomes data from all cell therapy and bone marrow transplants.
Marco Ruella, M.D.
“When this case was identified, we did a detailed analysis and concluded the T cell lymphoma was not related to the CAR T cell therapy. As the news of other cases came to light, we knew we should go deeper, to comb through our own data to better understand and help define the risk of any type of secondary cancer in patients who have received CAR T cell products,” said senior author Marco Ruella, MD, an assistant professor of Hematology-Oncology and Scientific Director of the Lymphoma Program. “What we found was very encouraging and reinforces the overall safety profile for this type of personalized cell therapy.”
Noor Momin, Stephenson Foundation Term Assistant Professor of Innovation
While growing up, Noor Momin, who joined the Department of Bioengineering in January as the Stephenson Foundation Term Assistant Professor of Innovation, imagined becoming a physician. Becoming a doctor seemed like a tangible way for someone interested in science to make a difference. Not until college did she realize the impact she could have as a bioengineer instead.
“I was taping microscope slides together,” Momin recalls of her initial experience as an undergraduate researcher at the University of Texas at Austin. “I didn’t even know what a Ph.D. was.”
It wasn’t until co-authoring her first paper, which explores how lipids, the water-repelling molecules that make up cell membranes (and also fats and oils), can switch between more fluid and less fluid arrangements, that Momin understood the degree to which bioengineering can influence medicine. “Someone could potentially use that paper for drug design,” Momin says.
As Momin sees it, the conventional wisdom of treating the heart like a mechanical pump, whose pipes can be replaced or whose throughput can be treated to prevent clogging in the first place, overshadows the immune system’s critical role in the development of heart disease.
A pair of proteins, YAP and TAZ, has been identified as conductors of bone development in the womb and could provide insight into genetic diseases such as osteogenesis imperfecta, known commonly as “brittle bone disease.” This research, published in Developmental Cell and led by members of the McKay Orthopaedic Research Laboratory of the Perelman School of Medicine, adds understanding to the field of mechanobiology, which studies how mechanical forces influence biology.
“Despite more than a century of study on the mechanobiology of bone development, the cellular and molecular basis largely has remained a mystery,” says the study’s senior author, Joel Boerckel, an associate professor of orthopaedic surgery. “Here, we identify a new population of cells that are key to turning the body’s early cartilage template into bone, guided by the force-activated gene regulating proteins, YAP and TAZ.”
Riccardo Gottardi, Assistant Professor in Pediatrics and in Bioengineering and leader of the Bioengineering and Biomaterials Laboratory at the Children’s Hospital of Philadelphia (CHOP), received the Rising Star Award from the Biomedical Engineering Society-Cellular and Molecular Bioengineering (BMES-CMBE). The Rising Star Award recognizes a BMES-CMBE member who is at the early independent career stage and has made an outstanding impact on the field of cellular and molecular bioengineering. Awardees will give an oral presentation on their research at the BMES-CMBE conference in Puerto Rico in January and be recognized at the conference Gala dinner.
Dr. Gottardi’s research focuses on engineering solutions for pediatric health, primarily for airway disorders. He has previously received awards for work to create a biomaterial patch to repair the tympanic membrane and for work to develop cartilage implants to treat severe subglottic stenosis. He received grant support from the National Institutes of Health to further his work in subglottic stenosis.
Sydney Shaffer, Assistant Professor in Bioengineering in the School of Engineering and Applied Science and in Pathology and Laboratory Medicine in the Perelman School of Medicine, was named the 2023 Christopher J. Marshall Award winner by the Society for Melanoma Research (SMR). The award recognizes Shaffer’s contributions to melanoma research on oncogenic signalling and molecular pathogenesis of this disease, as well as her rapid development as a rising star and leader in the field, which have helped to further the SMR’s goal to eradicate melanoma. The award was presented at the SMR annual meeting in Philadelphia in November 2023.
The Christopher J. Marshall Award was established in 2015 by the SMR in partnership with Melanoma Research Foundation Congress to recognize a student, postdoctoral fellow, or new independent PI who has published a substantial and original contribution to studies of signal transduction and melanoma.
Shaffer joined Penn as an Assistant Professor in 2019. She holds a M.D.-Ph.D. in Medicine and Bioengineering from the University of Pennsylvania and conducted postdoctoral research in cancer biology in the lab of Junwei Shi, Associate Professor in Penn Medicine. The Syd Shaffer Lab is an interdisciplinary team which focuses on “understanding how differences between single-cells generate phenotypes such as drug resistance, oncogenesis, differentiation, and invasion [using] a combination of imaging and sequencing technologies to investigate rare single-cell phenomena.” A recent paper in Nature Communications details the team’s method to quantify long-lived fluctuations in gene expression that are predictive of later resistance to targeted therapy for melanoma.
Read the award announcement and the full list of prior winners at the SMR website.
We hope you will join us for the 2023 Herman P. Schwan Distinguished Lecture by Dr. Dorin Comaniciu, hosted by the Department of Bioengineering.
Wednesday, December 13, 2023 1:00 PM ET Location: Wu & Chen Auditorium (Levine 101) The lecture and Q&A will be followed by a light reception in Levine Lobby.
Speaker:Dorin Comaniciu, Ph.D. Senior Vice President Artificial Intelligence and Digital Innovations Siemens Healthineers
About Dorin Comaniciu:
Dr. Comaniciu serves as Senior Vice President for Artificial Intelligence and Digital Innovation at Siemens Healthineers. His scientific contributions to machine intelligence and computational imaging have translated to multiple clinical products focused on improving the quality of care, specifically in the fields of diagnostic imaging, image-guided therapy, and precision medicine.
Comaniciu is a member of the National Academy of Medicine, the Romanian Academy, and a Top Innovator of Siemens. He is a Fellow of the IEEE, ACM, MICCAI Society, and AIMBE, and a recipient of the IEEE Longuet-Higgins Prize for fundamental contributions to computer vision. Recent recognition of his work includes an honorary doctorate from Friedrich-Alexander University of Erlangen-Nuremberg.
He has co-authored 550 granted patents and 350 peer-reviewed publications that have received 61,000 citations, with an h-index of 102, in the areas of machine intelligence, medical imaging, and precision medicine.
A graduate of University of Pennsylvania’s Wharton School, Comaniciu received a doctorate in electrical and computer engineering from Rutgers University and a doctorate in electronics and telecommunications from Polytechnic University of Bucharest.
He is an advocate for technological innovations that save and enhance lives, addressing critical issues in global health.
About the Schwan Lecture:
The Herman P. Schwan Distinguished Lecture is in honor of one of the founding members of the Department of Bioengineering, who emigrated from Germany after World War II and helped create the field of bioengineering in the US. It recognizes people with a similar transformative impact on the field of bioengineering.
Vaccines for COVID-19 were the first time that mRNA technology was used to address a worldwide health challenge. The Penn Medicine scientists behind that technology were awarded the 2023 Nobel Prize in Physiology or Medicine. Next come all the rest of the potential new treatments made possible by their discoveries.
But curbing the pandemic was only the beginning of the potential for this Nobel Prize-winning technology.
These biomedical innovations from Penn Medicine in using mRNA represent a multi-use tool, not just a treatment for a single disease. The technology’s potential is virtually unlimited; if researchers know the sequence of a particular protein they want to create or replace, it should be possible to target a specific disease. Through the Penn Institute for RNA Innovation led by Weissman, who is the Roberts Family Professor of Vaccine Research in Penn’s Perelman School of Medicine, researchers are working to ensure this limitless potential meets the world’s most challenging and important needs.
Infectious Diseases and Beyond
Just consider some of the many projects Weissman’s lab is partnering in: “We’re working on malaria with people across the U.S. and in Africa,” Weissman said. “We’re working on leptospirosis with people in Southeast Asia. We’re working on vaccines for peanut allergies. We’re working on vaccines for autoimmunity. And all of this is through collaboration.”
Clinical trials are underway for the new malaria vaccine, as well as for a Penn-developed mRNA vaccine for genital herpes and one that aims to protect against all varieties of coronaviruses. Trials should begin soon for vaccines for norovirus and the bacterium C. difficile.
Single-Injection Gene Therapies for Sickle Cell and Heart Disease
Drew Weissman, MD, PhD, is a co-winner of the 2023 Nobel Prize in Physiology or Medicine for discoveries with mRNA.
The Weissman lab is working to deploy mRNA technology as an accessible gene therapy for sickle cell anemia, a devastating and painful genetic disease that affects about 20 million people around the world. About 300,000 babies are born each year with the condition, mainly in sub-Saharan Africa. Weissman’s team has developed technology to efficiently deliver modified mRNA to bone marrow stem cells, instructing red blood cells to produce normal hemoglobin instead of the malformed “sickle” version that causes the illness. Conventional gene therapies are complex and expensive treatments, but the mRNA gene therapy could be a simple, one-time intravenous injection to cure the disease. Such a treatment would have applications to many other congenital gene defects in blood and stem cells.
In another new program, Penn Medicine researchers have found a way to target the muscle cells of the heart. This gene therapy method developed by Weissman’s team, together with Vlad Muzykantov, MD, PhD, the Founders Professor in Nanoparticle Research could potentially repair the heart or increase blood flow to the heart, noninvasively, after a heart attack or to correct a genetic deficiency in the heart. “That is important because heart disease is the number one killer in the U.S. and in the world,” Weissman said. “Drugs for heart disease aren’t specific for the heart. And when you’re trying to treat a myocardial infarction or cardiomyopathy or other genetic deficiencies in the heart, it’s very difficult, because you can’t deliver to the heart.”
Weissman’s team also is partnering on programs for neurodevelopmental diseases and for neurodegenerative diseases, to replace genes or deliver therapeutic proteins that will treat and potentially cure these diseases.
“The potential is unbelievable,” Weissman said. “We haven’t thought of everything that can be done.”
Vladimir R. Muzykantov is Founders Professor in Nanoparticle Research in the Department of Systems Pharmacology and Translational Therapeutics in the Perelman School of Medicine. He is a member of the Penn Bioengineering Graduate Group.
