Targeted Prenatal Therapy for Mothers and Their Babies Addresses Longstanding Gap in Health Equity

by

The research team from left to right includes Kelsey Swingle, Hannah Safford, Alex Hamilton, Ajay Thatte, Hannah Geisler, and Mike Mitchell.

New research on reproductive health demonstrates the first successful delivery of mRNA to placental cells to treat pre-eclampsia at its root.

Pre-eclampsia is a leading cause of stillbirths and prematurity worldwide, occurring in 3 – 8 % of pregnancies. A disorder characterized by high maternal blood pressure, it results from insufficient vasodilation in the placenta, restricting blood flow from the mother to the fetus.

Currently, a health-care plan for someone with pre-eclampsia involves diet and movement changes, frequent monitoring, blood pressure management, and sometimes early delivery of the baby. These standards of care address symptoms of the condition, not the root cause, and further perpetuate health inequity.

Now, Penn engineers are addressing this longstanding gap in reproductive health care with targeted RNA therapy.

The COVID vaccines demonstrated how lipid nanoparticles (LNPs) efficiently deliver mRNA to target cells. The success of LNPs is opening doors for a variety of RNA therapies aiming to treat the root causes of illness and disease. However, drug development and health care have consistently neglected a portion of the population in need of targeted care the most – pregnant people and their babies.

Targeted Treatment for Pre-eclampsia. Current treatment: Early delivery. Results in high maternal blood pressure, restricted blood flow to the fetus. New treatment: Targeted RNA therapy and blood pressure monitoring. Strategically designed Lipid Nanoparticles deliver mRNA to placental cells. Vascular endothelial growth factor expands blood vessels, restores blood flow.In one of the first studies of its kind, published in the Journal of the American Chemical Society, Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in Bioengineering, and Kelsey Swingle, Ph.D. student in the Mitchell Lab and lead author, describe their development of an LNP with the ability to target and deliver mRNA to trophoblasts, endothelial cells, and immune cells in the placenta.

Once these cells receive the mRNA, they create vascular endothelial growth factor (VEGF), a protein that helps expand the blood vessels in the placenta to reduce the mother’s blood pressure and restore adequate circulation to the fetus. The researchers’ successful trials in mice may lead to promising treatments for pre-eclampsia in humans.

Read the full story in Penn Engineering Today.

Inside the Mitchell Lab: Crossing Biological Barriers

by

Black and white photo of Mike Mitchell working in the lab.
Mike Mitchell, Ph.D.

Engineers in the Center for Precision Engineering for Health (CPE4H) are focusing on innovations in diagnostics and delivery, cellular and tissue engineering, and the development of new devices that integrate novel materials with human tissues. Below is an excerpt from “Going Small to Win Big: Engineering Personalized Medicine,” featuring the research from the laboratory of Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in Bioengineering.

The Challenge

Solid tumors evade the immune system’s ability to attack them in part due to the tumors’ tough, fibrous biological barriers that circulating immune cells can’t cross. Researchers need to identify ways to deliver individualized treatments that can better target these tumors without causing damage to healthy tissues or affecting overall quality of life.

The Status Quo

Current cancer treatments typically involve surgery, radiation or chemo- therapy to eliminate solid tumors. These treatments are invasive and can cause numerous negative downstream effects. Newer treatments involve engineering a patient’s immune system to recognize and fight cancerous cells, but are so far only effective against certain “liquid” cancers, where the mutated cells circulate freely in the blood and bone marrow and are small enough to be picked off by the patient’s upgraded T cells. Additionally, existing methods can also require that the cell engineering take place in a lab rather than directly inside the body.

The Mitchell Lab’s Fix

Members of the lab of Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in Bioengineering, are looking to utilize nanoparticle delivery technology developed by their lab to engineer a different type of immune cell, the macrophage, in order to fight solid- tumor cancers from the inside.

The Mitchell lab is using lipid nanoparticles (LNPs) to carry mRNA and DNA sequences inside of macrophages, a type of immune cell that can consume tumor cells if engineered correctly. In theory, a patient would receive an injection carrying the LNP payload, and the macrophages, whose name literally means “big eaters,” would take up the genetic sequence, alter their function and be able to recognize a patient’s own unique tumor cells in the body.

Because of the way macrophages operate, they could cross the tumor’s biological barrier and attack the cells, destroying the tumor from the inside. An added benefit of the Mitchell Lab’s technology is that the destroyed tumor cells would then also allow other immune cells to present their antigens to circulating T cells, which could then learn to fight those same cancer cells in the future.

“One of the longstanding challenges that we face in the context of cancer and immunotherapies is that every tumor has unique antigens that are specific to patients,” says Mitchell. “This is why we’ve had a lot of trouble developing targeted therapies. Personalizing an approach by harnessing an individual’s immune system gives each patient a greater chance of a positive outcome.”

Read the full story in Penn Engineering magazine.

RNA Lipid Nanoparticle Engineering Stops Liver Fibrosis in its Tracks, Reverses Damage

by

Members of the research team include (from left to right) Xuexiang Han, Michael J. Mitchell, Ningqiang Gong, Lulu Xue, Sarah J. Shepherd, and Rakan El-Mayta.
Members of the research team include (from left to right) Xuexiang Han, Michael J. Mitchell, Ningqiang Gong, Lulu Xue, Sarah J. Shepherd, and Rakan El-Mayta.

Since the success of the COVID-19 vaccine, RNA therapies have been the object of increasing interest in the biotech world. These therapies work with your body to target the genetic root of diseases and infections, a promising alternative treatment method to that of traditional pharmaceutical drugs.

Lipid nanoparticles (LNPs) have been successfully used in drug delivery for decades. FDA-approved therapies use them as vehicles for delivering messenger RNA (mRNA), which prompts the cell to make new proteins, and small interfering RNA (siRNA), which instruct the cell to silence or inhibit the expression of certain proteins.

The biggest challenge in developing a successful RNA therapy is its targeted delivery. Research is now confronting the current limitations of LNPs, which have left many diseases without an effective RNA therapy.

Liver fibrosis occurs when the liver is repeatedly damaged and the healing process results in the accumulation of scar tissue, impeding healthy liver function. It is a chronic disease characterized by the buildup of excessive collagen-rich extracellular matrix (ECM). Liver fibrosis has remained challenging to treat using RNA therapies due to a lack of delivery systems for targeting activated liver-resident fibroblasts. Both the solid fibroblast structure and the lack of specificity or affinity to target these fibroblasts has impeded current LNPs from entering activated liver-resident fibroblasts, and thus they are unable to deliver RNA therapeutics.

To tackle this issue and help provide a treatment for the millions of people who suffer from this chronic disease, Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, and postdoctoral fellows Xuexiang Han and Ningqiang Gong, found a new way to synthesize ligand-tethered LNPs, increasing their selectivity and allowing them to target liver fibroblasts.

Lulu Xue, Margaret Billingsley, Rakan El-Mayta, Sarah J. Shepherd, Mohamad-Gabriel Alameh and Drew Weissman, Roberts Family Professor in Vaccine Research and Director of the Penn Institute for RNA Innovation at the Perelman School of Medicine, also contributed to this work.

Read the full story in Penn Engineering Today.

2022 Career Award Recipient: Michael Mitchell

by Melissa Pappas

Michael Mitchell (Illustration by Melissa Pappas)

Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, is one of this year’s recipients of the National Science Foundation’s CAREER Award. The award is given to early-career faculty researchers who demonstrate the potential to be role models in their field and invest in the outreach and education of their work.

Mitchell’s award will fund research on techniques for “immunoengineering” macrophages. By providing new instructions to these cells via nanoparticles laden with mRNA and DNA sequences, the immune system could be trained to target and eliminate solid tumors. The award will also support graduate students and postdoctoral fellows in his lab over the next five years.

The project aligns with Mitchell’s larger research goals and the current explosion of interest in therapies that use mRNA, thanks to the technological breakthroughs that enabled the development of COVID-19 vaccines.

“The development of the COVID vaccine using mRNA has opened doors for other cell therapies,” says Mitchell. “The high-priority area of research that we are focusing on is oncological therapies, and there are multiple applications for mRNA engineering in the fight against cancer.”

A new wave of remarkably effective cancer treatments incorporates chimeric antigen receptor T-cell (CAR-T) therapy. There, a patient’s T-cells, a type of white blood cell that fights infections, are genetically engineered to identify, target and kill individual cancer cells that accumulate in the circulatory system.

However, despite CART-T therapy’s success in treating certain blood cancers, the approach is not effective against cancers that form solid tumors. Because T-cells are not able to penetrate tumors’ fibrous barriers, Mitchell and his colleagues have turned to another part of the immune system for help.

Read the full story in Penn Engineering Today.

Herman P. Schwan Distinguished Lecture: “Nucleoside-modified mRNA-LNP therapeutics” (Drew Weissman, Perelman School of Medicine)

We hope you will join us for the Spring 2022 Herman P. Schwan Distinguished Lecture by Dr. Drew Weissman, hosted by the Department of Bioengineering.

Date: Tuesday, March 29, 2022
Time: 3:30-5:00 PM
Location: Bodek Lounge, Houston Hall
Reception to follow
Zoom Link
Password: schwan22

Drew Weissman, M.D., Ph.D.

Speaker: Drew Weissman, M.D., Ph.D.
Roberts Family Professor in Vaccine Research, Department of Medicine
Perelman School of Medicine
University of Pennsylvania

Abstract:

Vaccines prevent 4-5 million deaths a year making them the principal tool of medical intervention worldwide. Nucleoside-modified mRNA was developed over 15 years ago and has become the darling of the COVID-19 pandemic with the first 2 FDA approved vaccines based on it. These vaccines show greater than 90% efficacy and outstanding safety in clinical use. The mechanism for the outstanding immune response induction are the prolonged production of antigen leading to continuous loading of germinal centers and the adjuvant effect of the LNPs, which selectively stimulate T follicular helper cells that drive germinal center responses. Vaccine against many pathogens, including HIV, HCV, HSV2, CMV, universal influenza, coronavirus variants, pancoronavirus, nipah, norovirus, malaria, TB, and many others are currently in development. Nucleoside-modified mRNA is also being developed for therapeutic protein delivery. Clinical trials with mRNA encoded monoclonal antibodies are underway and many other therapeutic or genetic deficient proteins are being developed. Finally, nucleoside-modified mRNA-LNPs are being developed and used for gene therapy. Cas9 knockout to treat transthyretin amyloidosis has shown success in phase 1 trials. We have developed the ability to target specific cells and organs, including lung, brain, heart, CD4+ cells, all T cells, and bone marrow stem cells, with LNPs allowing specific delivery of gene editing and insertion systems to treat diseases such as sickle cell anemia, Nucleoside-modified mRNA will have an enormous potential in the development of new medical therapies.

Bio:

Drew Weissman, M.D., Ph.D. is a professor of Medicine at the Perelman School of Medicine, University of Pennsylvania. He received his graduate degrees from Boston University School of Medicine. Dr. Weissman, in collaboration with Dr. Katalin Karikó, discovered the ability of modified nucleosides in RNA to suppress activation of innate immune sensors and increase the translation of mRNA containing certain modified nucleosides. The nucleoside-modified mRNA-lipid nanoparticle vaccine platform Dr. Weissman’s lab created is used in the first 2 approved COVID-19 vaccines by Pfizer/BioNTech and Moderna. They continue to develop other vaccines that induce potent antibody and T cell responses with mRNA–based vaccines. Dr. Weissman’s lab also develops methods to replace genetically deficient proteins, edit the genome, and specifically target cells and organs with mRNA-LNPs, including lung, heart, brain, CD4+ cells, all T cells, and bone marrow stem cells.

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.

Penn Engineers Secure Wellcome Leap Contract for Lipid Nanoparticle Research Essential in Delivery of RNA Therapies

by Melissa Pappas

The Very Large Scale Microfluidic Integration (VLSMI) platform, a technology developed by the Penn researchers, contains hundreds of mixing channels for mass-producing mRNA-carrying lipid nanoparticles.

Penn Engineering secured a multi-million-dollar contract with Wellcome Leap under the organization’s $60 million RNA Readiness + Response (R3) program, which is jointly funded with the Coalition for Epidemic Preparedness Innovations (CEPI). Penn Engineers aim to create “on-demand” manufacturing technology that can produce a range of RNA-based vaccines.

The Penn Engineering team features Daeyeon Lee, Evan C Thompson Term Chair for Excellence in Teaching and Professor in Chemical and Biomolecular Engineering, Michael Mitchell, Skirkanich Assistant Professor of Innovation in Bioengineering, David Issadore, Associate Professor in Bioengineering and Electrical and Systems Engineering, and Sagar Yadavali, a former postdoctoral researcher in the Issadore and Lee labs and now the CEO of InfiniFluidics, a spinoff company based on their research. Drew Weissman of the Perelman School of Medicine, whose foundational research directly continued to the development of mRNA-based COVID-19 vaccines, is also a part of this interdisciplinary team.

The success of these COVID-19 vaccines has inspired a fresh perspective and wave of research funding for RNA therapeutics across a wide range of difficult diseases and health issues. These therapeutics now need to be equitably and efficiently distributed, something currently limited by the inefficient mRNA vaccine manufacturing processes which would rapidly translate technologies from the lab to the clinic.

Read more in Penn Engineering Today.

New Lipid Nanoparticles Improve mRNA Delivery for Engineering CAR T Cells

by Melissa Pappas

The Penn researchers’ latest paper on the design of lipid nanoparticles was featured on the cover of the most recent edition of the journal Nano Letters.

From COVID vaccines to cancer immunotherapies to the potential for correcting developmental disorders in utero, mRNA-based approaches are a promising tool in the fight against a wide range of diseases. These treatments all depend on providing a patient’s cells with genetic instructions for custom proteins and other small molecules, meaning that getting those instructions inside the target cells is of critical importance.

The current delivery method of choice uses lipid nanoparticles (LNPs). Thanks to surfaces customized with binding and signaling molecules, they encapsulate mRNA sequences and smuggle them through the cell membrane. But with a practically unlimited number of variables in the makeup of those surfaces and molecules, figuring out how to design the most effective LNP is a fundamental challenge.

Now, in a study featured on the cover of the journal Nano Letters, researchers from the University of Pennsylvania’s School of Engineering and Applied Science and Perelman School of Medicine have now shown how to computationally optimize the design of these delivery vehicles.

Using an established methodology for comparing a wide range of variables known as “orthogonal design of experiments,” the researchers simultaneously tested 256 candidate LNPs. They found the frontrunner was three times better at delivering mRNA sequences into T cells than the current standard LNP formulation for mRNA delivery.

The study was led by Michael Mitchell, Skirkanich Assistant Professor of Innovation in the Department of Bioengineering in Penn’s School of Engineering and Applied Science, and Margaret Billingsley, a graduate student in his lab.

Read the full story in Penn Engineering Today.

Penn Engineers Will Use NSF Grant to Develop ‘DReAM’ for On-demand, On-site mRNA Manufacturing

by Melissa Pappas

Daeyeon Lee, Kathleen Stebe and Michael Mitchell

COVID-19 vaccines are just the beginning for mRNA-based therapies; enabling a patient’s body to make almost any given protein could revolutionize care for other viruses, like HIV, as well as various cancers and genetic disorders. However, because mRNA molecules are very fragile, they require extremely low temperatures for storage and transportation. The logistical challenges and expense of maintaining these temperatures must be overcome before mRNA therapies can become truly widespread.

With these challenges in mind, Penn Engineering researchers are developing a new manufacturing technique that would be able to produce mRNA sequences on demand and on-site, isolating them in a way that removes the need for cryogenic temperatures. With more labs able to make and store mRNA-based therapeutics on their own, the “cold chain” between manufacturer and patient can be made shorter, faster and less expensive.

The National Science Foundation (NSF) is supporting this project, known as Distributed Ribonucleic Acid Manufacturing, or DReAM, through a four-year, $2 million grant from its Emerging Frontiers in Research and Innovation (EFRI) program.

The project will be led by Daeyeon Lee, Evan C Thompson Term Chair for Excellence in Teaching and Professor in the Department of Chemical and Biomolecular Engineering (CBE), along with Kathleen Stebe, Richer and Elizabeth Goodwin Professor in CBE and in the Department of Mechanical Engineering and Applied Mechanics. They will collaborate with Michael Mitchell, Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, Drexel University’s Masoud Soroush and Michael Grady, the University of Oklahoma’s Dimitrios Papavassiliou and the University of Colorado Boulder’s Joel Kaar.

Read the full story in Penn Engineering Today.

With a ‘Liquid Assembly Line,’ Penn Researchers Produce mRNA-Delivering-Nanoparticles a Hundred Times Faster than Standard Microfluidic Technologies

by Evan Lerner

Michael Mitchell, Sarah Shepherd and David Issadore pose with their new device.

The COVID vaccines currently being deployed were developed with unprecedented speed, but the mRNA technology at work in some of them is an equally impressive success story. Because any desired mRNA sequence can be synthesized in massive quantities, one of the biggest hurdles in a variety of mRNA therapies is the ability to package those sequences into the lipid nanoparticles that deliver them into cells.

Now, thanks to manufacturing technology developed by bioengineers and medical researchers at the University of Pennsylvania, a hundred-fold increase in current microfluidic production rates may soon be possible.

The researchers’ advance stems from their design of a proof-of-concept microfluidic device containing 128 mixing channels working in parallel. The channels mix a precise amount of lipid and mRNA, essentially crafting individual lipid nanoparticles on a miniaturized assembly line.

This increased speed may not be the only benefit; more precisely controlling the nanoparticles’ size could make treatments more effective. The researchers tested the lipid nanoparticles produced by their device in a mouse study, showing they could deliver therapeutic RNA sequences with four-to-five times greater activity than those made by conventional methods.

The study was led by Michael Mitchell, Skirkanich Assistant Professor of Innovation in Penn Engineering’s Department of Bioengineering, and David Issadore, Associate Professor in Penn Engineering’s Department of Bioengineering, along with Sarah Shepherd, a doctoral student in both of their labs. Rakan El-Mayta, a research engineer in Mitchell’s lab, and Sagar Yadavali, a postdoctoral researcher in Issadore’s lab, also contributed to the study.

They collaborated with several researchers at Penn’s Perelman School of Medicine: postdoctoral researcher Mohamad-Gabriel Alameh, Lili Wang, Research Associate Professor of Medicine, James M. Wilson, Rose H. Weiss Orphan Disease Center Director’s Professor in the Department of Medicine, Claude Warzecha, a senior research investigator in Wilson’s lab, and Drew Weissman, Professor of Medicine and one of the original developers of the technology behind mRNA vaccines.

It was published in the journal Nano Letters.

“We believe that this microfluidic technology has the potential to not only play a key role in the formulation of current COVID vaccines,” says Mitchell, “but also to potentially address the immense need ahead of us as mRNA technology expands into additional classes of therapeutics.”

Read the full story in Penn Engineering Today.

‘RNA worked for COVID-19 vaccines. Could it be used to treat cancer and rare childhood diseases?’

William H. Peranteau, Michael J. Mitchell, Margaret Billingsley, Meghana Kashyap, and Rachel Riley (Clockwise from top left)

As COVID-19 vaccines roll out, the concept of using mRNA to fend off viruses has become a part of the public dialogue. However, scientists have been researching how mRNA can be used to in life-saving medical treatments well before the pandemic.

The “m” in “mRNA” is for “messenger.” A single-stranded counterpart to DNA, it translates the genetic code into the production of proteins, the building blocks of life. The Moderna and Pfizer COVID-19 vaccines work by introducing mRNA sequences that act as a set of instructions for the body to produce proteins that mimic parts of the virus itself. This prepares the body’s immune response to recognize the real virus and fight it off.

Because it can spur the production of proteins that the body can’t make on its own, mRNA therapies also have the potential to slow or prevent genetic diseases that develop before birth, such as cystic fibrosis and sickle-cell anemia.

However, because mRNA is a relatively unstable molecule that degrades quickly, it needs to be packaged in a way that maintains its integrity as its delivered to the cells of a developing fetus.

To solve this challenge, Michael J. Mitchell, Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, is researching the use of lipid nanoparticles as packages that transport mRNA into the cell. He and William H. Peranteau, an attending surgeon in the Division of General, Thoracic and Fetal Surgery and the Adzick-McCausland Distinguished Chair in Fetal and Pediatric Surgery at Children’s Hospital of Philadelphia, recently co-authored a “proof-of-concept” paper investigating this technique.

In this study, published in Science Advances, Mitchel examined which nanoparticles were optimal in the transport of mRNA to fetal mice. Although no disease or organ was targeted in this study, the ability to administer mRNA to a mouse while still in the womb was demonstrated, and the results are promising for the next stages of targeted disease prevention in humans.

Mitchel spoke with Tom Avril at The Philadelphia Inquirer about the mouse study and its implications for treatment of rare infant diseases through the use of mRNA, ‘the messenger of life.’

Penn bioengineering professor Michael J. Mitchell, the other senior author of the mouse study, tested various combinations of lipids to see which would work best.

The appeal of the fatty substances is that they are biocompatible. In the vaccines, for example, two of the four lipids used to make the delivery spheres are identical to lipids found in the membranes of human cells — including plain old cholesterol.

When injected, the spheres, called nanoparticles, are engulfed by the person’s cells and then deposit their cargo, the RNA molecules, inside. The cells respond by making the proteins, just as they make proteins by following the instructions in the person’s own RNA. (Important reminder: The RNA in the vaccines cannot become part of your DNA.)

Among the different lipid combinations that Mitchell and his lab members tested, some were better at delivering their cargo to specific organs, such as the liver and lungs, meaning they could be a good vehicle for treating disease in those tissues.

Continue reading Tom Avril’s ‘RNA worked for COVID-19 vaccines. Could it be used to treat cancer and rare childhood diseases?’ at The Philadelphia Inquirer.