How Penn Medicine Is Changing the World with mRNA

by Rachel Ewing

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.

Starting in the late 1990s, working together at Penn Medicine, Katalin Karikó, PhD, and Drew Weissman, MD, PhD, discovered how to safely use messenger RNA (mRNA) as a whole new type of vaccine or therapy for diseases. When the COVID-19 pandemic hit in 2020, these discoveries made Pfizer/BioNTech and Moderna’s new vaccines possible—saving millions of lives. 

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.”

Read the full story in Penn Medicine News.

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.

Penn Partners in Multi-University Research Center Supporting Healthy Pregnancies

by Andrew Smith

How does the placenta keep harmful substances away from developing babies while still providing proper nutrition?

(Photo: Getty Images)

The exact mechanisms remain unknown, which is why the University of Pennsylvania, Rutgers University, Tulane University, the University of North Carolina at Chapel Hill and the University of Rochester have joined together to launch a research center dedicated to solving this mystery and ensuring healthy pregnancies.

A $5 million grant from the National Institutes of Health (NIH) will help fund the Integrated Transporter Elucidation Center (InTEC), which will operate from the Rutgers Biomedical Health Sciences campus in Piscataway under the leadership of Lauren Aleksunes, a professor of pharmacology and toxicology at Rutgers’ Ernest Mario School of Pharmacy and resident scientist in the Environmental and Occupational Health Sciences Institute (EOHSI).

“Since my time working as a community pharmacist, I have found the lack of high-quality information about the safety of everyday products on the health of a pregnancy frustrating,” says Aleksunes.  “People need to know whether the chemicals in their diet, personal care products and medications can impact their babies. Our goal at InTEC is to better understand how these chemicals travel in and out of the placenta and if they can reach the baby and influence their development.”

Aleksunes will study how transporter proteins carrying nutrients, dietary supplements, medications and toxic chemicals work during pregnancies. Some of the work will test how individual placenta cells respond to various stimuli in the laboratory. Others on the team will examine how environmental factors influence placental transporters during healthy and unhealthy or complicated pregnancies. 

Key to this work will be Dan Huh, Associate Professor in Bioengineering in Penn Engineering, who will lead a team with an innovative approach to modeling the transfer of molecules across the human placenta. 

As a pioneer of organ-on-a-chip technology, the Huh group will use a novel microengineered system in which maternal tissue engineered from a layer of primary human trophoblasts is grown adjacent to a three-dimensional network of perfusable fetal blood vessels to mimic the human placental barrier. This microphysiological system will be employed as an in vitro platform to simulate and quantitatively analyze the exchange of various substances between maternal and fetal circulation without the need for laboratory animals or placenta explants.

Read the full story in Penn Engineering Today.

Why New Cancer Treatments are Proliferating

by Karen L. Brooks

Doctors performing surgery.
Image: Penn Medicine News

In the five years since the FDA’s initial approval of chimeric antigen receptor (CAR) T cell therapy, Penn Medicine has gleaned 20 additional approvals related to drugs and techniques to treat or detect cancer.

Rather than being the single disease class many people refer to, “cancer” is a blanket term that covers more than 100 distinct diseases, many of which have little in common aside from originating with rapidly dividing cells. Since different cancers demand different treatments, it follows that any given new therapy emerging from any institution would be likely to be a new cancer treatment.

But why so many in just this five-year period?

The volume of new cancer treatments makes sense, says Abramson Cancer Center (ACC) director Robert Vonderheide, attributing the flurry of new cancer drug approvals to a recent “explosion” in knowledge about cancer biology.

“Much of that knowledge is about the immune system’s ability to attack cancer, which people seriously doubted until about 20 years ago. As soon as we had a clinical validation for this Achilles heel in cancer, the dam burst for ideas about other ways to exploit that vulnerability to come forward,” he says. “The first drug that came out to activate the immune system inspired the rest of the field to find the next drug, and the one after that. We as a field have moved from serendipity and empiricism to science-driven drug design.”

The first CAR T cell therapy approval invigorated Penn faculty interested in finding new ways to harness the immune system to fight cancer.

“An approval like that makes what you’re working on more of a reality,” says Avery Posey, an assistant professor of systems pharmacology and translational therapeutics in the Perelman School of Medicine, whose lab team spends much of its time trying to identify more specific antigens for solid tumors and also studies ways to optimize engineered donor T cells. “It brings a new perspective, showing that your work is more than basic research and can actually become drugs that impact patients’ lives. That’s a real motivator to keep pushing forward.”

Honing new immunotherapies is a priority among Penn researchers, but not every recently approved new cancer treatment or detection tool developed at the institution engages the immune system. Faculty have explored and introduced widely varying approaches to improving the standard of care for cancer patients.

Read the full story in Penn Medicine Magazine.

Avery Posey is a member of the Penn Bioengineering Graduate Group. Read more stories featuring Posey here.

Carl June and Avery Posey Lead the Way in CAR T Cell Therapy

Perelman School of Medicine (PSOM) professors and Penn Bioengineering Graduate Group members Carl June and Avery Posey are leading the charge in T cell therapy and the fight against cancer.

Avery Posey, PhD

Carl June, MD

Advances in genome editing through processes such as CRISPR, and the ability to rewire cells through synthetic biology, have led to increasingly elaborate approaches for modifying and supercharging T cells for therapy. Avery Posey,  Assistant Professor of Pharmacology, and Carl June, the Richard W. Vague Professor in Immunotherapy, explain how new techniques are providing tools to counter some of the limitations of current CAR T cell therapies in a recent Nature feature.

The pair were also part of a team of researchers from PSOM, the Children’s Hospital of Philadelphia (CHOP), and the Corporal Michael J. Crescenz VA Medical Center to receive an inaugural $8 million Therapy ACceleration To Intercept CAncer Lethality (TACTICAL) Award from the Prostate Cancer Foundation. Their project will develop new clinic-ready CAR T cell therapies for Metastatic Castrate-Resistant Prostate Cancer (mCRPC).

Read “The race to supercharge cancer-fighting T cells” in Nature.

Read about the TACTICAL Award in the December 2022 Awards & Accolades section of Penn Medicine News.

Penn Startup Vittoria Biotherapeutics Raises $10M in Seed Funding

Marco Ruella, MD

A Philadelphia life sciences company spun out of Penn is emerging from stealth mode with nearly $10 million from a seed funding round. Vittoria Biotherapeutics’ mission is to overcome limitations of CAR T cell therapy by using unique cell engineering and gene editing technologies to create new therapies that address unmet clinical needs. The technology the company is attempting to commercialize was developed by Marco Ruella, M.D., Assistant Professor of Medicine in the Perelman School of Medicine and member of the Penn Bioengineering Graduate Group, who is the company’s scientific founder.

Read “Penn spinout Vittoria Biotherapeutics emerges from stealth mode with $10M seed round” in the Philadelphia Business Journal.

Nerve Repair, With Help From Stem Cells

A cross-disciplinary Penn team is pioneering a new approach to peripheral nerve repair.

In a new publication in the journal npj Regenerative Medicine, a team of Penn researchers from the School of Dental Medicine and the Perelman School of Medicine “coaxed human gingiva-derived mesenchymal stem cells (GMSCs) to grow Schwann-like cells, the pro-regenerative cells of the peripheral nervous system that make myelin and neural growth factors,” addressing the need for regrowing functional nerves involving commercially-available scaffolds to guide nerve growth. The study was led by Anh Le, Chair and Norman Vine Endowed Professor of Oral Rehabilitation in the Department of Oral and Maxillofacial Surgery/Pharmacology at the University of Pennsylvania School of Dental Medicine, and was co-authored by D. Kacy Cullen, Associate Professor in Neurosurgery at the Perelman School of Medicine at Penn and the Philadelphia Veterans Affairs Medical Center and member of the Bioengineering Graduate Group:

D. Kacy Cullen (Image: Eric Sucar)

“To get host Schwann cells all throughout a bioscaffold, you’re basically approximating natural nerve repair,” Cullen says. Indeed, when Le and Cullen’s groups collaborated to implant these grafts into rodents with a facial nerve injury and then tested the results, they saw evidence of a functional repair. The animals had less facial droop than those that received an “empty” graft and nerve conduction was restored. The implanted stem cells also survived in the animals for months following the transplant.

“The animals that received nerve conduits laden with the infused cells had a performance that matched the group that received an autograft for their repair,” he says. “When you’re able to match the performance of the gold-standard procedure without a second surgery to acquire the autograft, that is definitely a technology to pursue further.”

Read the full story and view the full list of collaborators in Penn Today.

Penn, CHOP and Yale Researchers’ Molecular Simulations Uncover How Kinase Mutations Lead to Cancer Progression

by Evan Lerner

A computer model of a mutated anaplastic lymphoma kinase (ALK), a known oncogenic driver in pediatric neuroblastoma.

Kinases are a class of enzymes that are responsible for transferring the main chemical energy source used by the body’s cells. As such, they play important roles in diverse cellular processes, including signaling, differentiation, proliferation and metabolism. But since they are so ubiquitous, mutated versions of kinases are frequently found in cancers. Many cancer treatments involve targeting these mutant kinases with specific inhibitors.

Understanding the exact genetic mutations that lead to these aberrant kinases can therefore be critical in predicting the progression of a given patient’s cancer and tailoring the appropriate response.

To achieve this understanding on a more fundamental level, a team of researchers from the University of Pennsylvania’s School of Engineering and Applied Science and Perelman School of Medicine, the Children’s Hospital of Philadelphia (CHOP) and researchers at the Yale School of Medicine’s Cancer Biology Institute, have constructed molecular simulations of a mutant kinase implicated in pediatric neuroblastoma, a childhood cancer impacting the central nervous system.

Using their computational model to study the relationship between single-point changes in the kinase’s underlying gene and the altered structure of the protein it ultimately produces, the researchers revealed useful commonalities in the mutations that result in tumor formation and growth. Their findings suggest that such computational approaches could outperform existing profiling methods for other cancers and lead to more personalized treatments.

The study, published in the Proceedings of the National Academy of Sciences, was led by Ravi Radhakrishnan, Professor and chair of Penn Engineering’s Department of Bioengineering and professor in its Department of Chemical and Biomolecular Engineering, and Mark A. Lemmon, Professor of Pharmacology at Yale and co-director of Yale’s Cancer Biology Institute. The study’s first authors were Keshav Patil, a graduate student in Penn Engineering’s Department of Chemical and Biomolecular Engineering, along with Earl Joseph Jordan and Jin H. Park, then members of the Graduate Group in Biochemistry and Molecular Biology in Penn’s Perelman School of Medicine. Krishna Suresh, an undergraduate student in Radhakrishnan’s lab, Courtney M. Smith, a graduate student in Lemmon’s lab, and Abigail A. Lemmon, an undergraduate in Lemmon’s lab, contributed to the study. They collaborated with Yaël P. Mossé, Associate Professor of Pediatrics at Penn Medicine and in the division of oncology at CHOP.

“Some cancers rely on the aberrant activation of a single gene product for tumor initiation and progression,” says Radhakrishnan. “This unique mutational signature may hold the key to understanding which patients suffer from aggressive forms of the disease or for whom a given therapeutic drug may yield short- or long-term benefits. Yet, outside of a few commonly occurring ‘hotspot’ mutations, experimental studies of clinically observed mutations are not commonly pursued.”

Read the full post in Penn Engineering Today.