Penn Engineers have pioneered a new way to visualize the smallest protein clusters, skirting the physical limitations of light-powered microscopes and opening new avenues for detecting the proteins implicated in diseases like Alzheimer’s and testing new treatments.
In a paper in Cell Systems, Lukasz Bugaj, Assistant Professor in Bioengineering, describes the creation of CluMPS, or Clusters Magnified by Phase Separation, a molecular tool that activates by forming conspicuous blobs in the presence of target protein clusters as small as just a few nanometers. In essence, CluMPS functions like an on/off switch that responds to the presence of clusters of the protein it is programmed to detect.
Normally, says Bugaj, detecting such clusters requires laborious techniques. “With CluMPS, you don’t need anything beyond the standard lab microscope.” The tool fuses with the target protein to form condensates orders of magnitude larger than the protein clusters themselves that resemble the colorful blobs in a lava lamp. “We think the simplicity of the approach is one of its main benefits,” says Bugaj. “You don’t need specialized skills or equipment to quickly see whether there are small clusters in your cells.”
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.
More than 34 million Americans suffer from pulmonary diseases like asthma, emphysema and chronic bronchitis. While medical treatments can keep these ailments in check, there are currently no cures. Part of the reason, notes Dan Huh, is that it’s incredibly hard to study how these diseases actually work. While researchers can grow cells taken from human lungs in a dish, they cannot expect them to act like they would in the body. In order to mimic the real deal, it’s necessary to recreate the complex, 3D environment of the lung — right down to its tiny air sacs and blood vessels — and to gently stretch and release the tissue to simulate breathing.
Huh, Associate Professor in Bioengineering, is the cofounder of Vivodyne, a Penn Engineering biotech spinoff that is creating tissues like these in the lab. Vivodyne uses a bioengineering technology that Huh has been developing for more than a decade. While a postdoctoral fellow at Harvard’s Wyss Institute, he played a central role in creating a novel device called an “organ on a chip,” which, as the name implies, assembles multiple cell types on a tiny piece of engineered plastic to create an approximation of an organ.
“While those chips represented a major innovation,” says Huh, “they still weren’t truly lifelike. They lacked many of the essential features of their counterparts in the human body, such as the network of blood vessels running between different kinds of tissue, which are essential for transporting oxygen, nutrients, waste products and various biochemical signals.”
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.
Imagine the brain as an air traffic control tower, overseeing the crucial and complex operations of the body’s ‘airport.’ This tower, essential for coordinating the ceaseless flow of neurological signals, is guarded by a formidable layer that functions like the airport’s security team, diligently screening everything and everyone, ensuring no unwanted intruders disrupt the vital workings inside.
However, this security, while vital, comes with a significant drawback: sometimes, a ‘mechanic’—in the form of critical medication needed for treating neurological disorders—is needed inside the control tower to fix arising issues. But if the security is too stringent, denying even these essential agents entry, the very operations they’re meant to protect could be jeopardized.
Now, researchers led by Michael Mitchell of the University of Pennsylvania are broaching this long-standing boundary in biology, known as the blood-brain barrier, by developing a method akin to providing this mechanic with a special keycard to bypass security. Their findings, published in the journal Nano Letters, present a model that uses lipid nanoparticles (LNPs) to deliver mRNA, offering new hope for treating conditions like Alzheimer’s disease and seizures—not unlike fixing the control tower’s glitches without compromising its security.
“Our model performed better at crossing the blood-brain barrier than others and helped us identify organ-specific particles that we later validated in future models,” says Mitchell, associate professor of bioengineering at Penn’s School of Engineering and Applied Science, and senior author on the study. “It’s an exciting proof of concept that will no doubt inform novel approaches to treating conditions like traumatic brain injury, stroke, and Alzheimer’s.”
Biofilms—structured communities of microorganisms that create a protective matrix shielding them from external threats, including antibiotics—are responsible for about 80% of human infections and present a significant challenge in medical treatments, often resisting conventional methods.
Q: What is the motivation behind opting for tiny robots to tackle infections?
Koo: Treating biofilms is a broad yet unresolved biomedical problem, and conversely, the strategies for tackling biofilms are limited for a number of reasons. For instance, biofilms typically occur on surfaces that can be tricky to reach, like between the teeth in the oral cavity, the respiratory tract, or even within catheters and implants, so treatments for these are usually restricted to antibiotics (or antimicrobials) and other physical methods reliant on mechanical disruption. However, this touches on the problem of antimicrobial resistance: targeting specific microorganisms present in these structures is difficult, so antibiotics often fail to reach and penetrate the biofilm’s protective layers, leading to persistent infections and increased risk of antibiotic resistance.
We needed a way to circumvent these constraints, so Ed and I teamed up in 2017 to develop new, more precise and effective approaches that leverage the engineers’ ability to generate solutions that we, the clinicians and life science researchers, identify.
Hyun (Michel) Koo is a professor in the Department of Orthodontics and in the divisions of Pediatric Dentistry and Community Oral Health and the co-founder of the Center for Innovation & Precision Dentistry in the School of Dental Medicine at the University of Pennsylvania. He is a member of the Penn Bioengineering Graduate Group.
Edward Steager is a senior research investigator in Penn’s School of Engineering and Applied Science.
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.
As a neuroscientist surveying the landscape of generative AI—artificial intelligence capable of generating text, images, or other media—Konrad Kording cites two potential directions forward: One is the “weird future” of political use and manipulation, and the other is the “power tool direction,” where people use ChatGPT to get information as they would use a drill to build furniture.
“I’m not sure which of those two directions we’re going but I think a lot of the AI people are working to move us into the power tool direction,” says Kording, a Penn Integrates Knowledge (PIK) University professor with appointments in the Perelman School of Medicine and School of Engineering and Applied Science. Reflecting on how generative AI is shifting the paradigm of science as a discipline, Kording said he thinks “it will push science as a whole into a much more collaborative direction,” though he has concerns about ChatGPT’s blind spots.
Kording joined three University of Pennsylvania researchers from the chemistry, political science, and psychology departments sharing their perspectives in the recent panel “ChatGPT turns one: How is generative AI reshaping science?” PIK Professor René Vidal opened the event, which was hosted by the School of Arts & Sciences’ Data Driven Discovery Initiative (DDDI), and Bhuvnesh Jain, physics and astronomy professor and co-faculty director of DDDI, moderated the discussion.
“Generative AI is moving so rapidly that even if it’s a snapshot, it will be very interesting for all of us to get that snapshot from these wonderful experts,” Jain said. OpenAI launched ChatGPT, a large language model (LLM)-based chatbot, on Nov. 30, 2022, and it rapidly ascended to ubiquity in news reports, faculty discussions, and research papers. Colin Twomey, interim executive director of DDDI, told Penn Today that it’s an open question as to how it will change the landscape of scientific research, and the` idea of the event was to solicit colleagues’ opinions on interesting directions in their fields.
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.
Each year, the Nemirovsky Engineering and Medicine Opportunity (NEMO) Prize, funded by Penn Health-Tech, awards $80,000 to a collaborative team of researchers from the University of Pennsylvania’s Perelman School of Medicine and the School of Engineering and Applied Science for early-stage, interdisciplinary ideas.
This year, the NEMO Prize has been awarded to Penn Engineering’s Daeyeon Lee, Russel Pearce and Elizabeth Crimian Heuer Professor in Chemical and Biomolecular Engineering, Oren Friedman, Associate Professor of Clinical Otorhinolaryngology in the Perelman School of Medicine, and Sergei Vinogradov, Professor in the Department of Biochemistry and Biophysics in the Perelman School of Medicine and the Department of Chemistry in the School of Arts & Sciences. Together, they are developing a new therapy that improves the survival and success of soft-tissue grafts used in reconstructive surgery.
More than one million people receive soft-tissue reconstructive surgery for reasons such as tissue trauma, cancer or birth defects. Autologous tissue transplants are those where cells and tissue such as fat, skin or cartilage are moved from one part of a patient’s body to another. As the tissue comes from the patient, there is little risk of transplant rejection. However, nearly one in four autologous transplants fail due to tissue hypoxia, or lack of oxygen. When transplants fail the only corrective option is more surgery. Many techniques have been proposed and even carried out to help oxygenate soft tissue before it is transplanted to avoid failures, but current solutions are time consuming and expensive. Some even have negative side effects. A new therapy to help oxygenate tissue quickly, safely and cost-effectively would not only increase successful outcomes of reconstructive surgery, but could be widely applied to other medical challenges.
The therapy proposed by this year’s NEMO Prize recipients is a conglomerate or polymer of microparticles that can encapsulate oxygen and disperse it in sustainable and controlled doses to specific locations over periods of time up to 72 hours. This gradual release of oxygen into the tissue from the time it is transplanted to the time it functionally reconnects to the body’s vascular system is essential to keeping the tissue alive.
“The microparticle design consists of an oxygenated core encapsulated in a polymer shell that enables the sustained release of oxygen from the particle,” says Lee. “The polymer composition and thickness can be controlled to optimize the release rate, making it adaptable to the needs of the hypoxic tissue.”
These life-saving particles are designed to be integrated into the tissue before transplantation. However, because they exist on the microscale, they can also be applied as a topical cream or injected into tissue after transplantation.
“Because the microparticles are applied directly into tissues topically or by interstitial injection (rather than being administered intravenously), they surpass the need for vascular channels to reach the hypoxic tissue,” says Friedman. “Their micron-scale size combined with their interstitial administration, minimizes the probability of diffusion away from the injury site or uptake into the circulatory system. The polymers we plan to use are FDA approved for sustained-release drug delivery, biocompatible and biodegrade within weeks in the body, presenting minimal risk of side effects.”
The research team is currently testing their technology in fat cells. Fat is an ideal first application because it is minimally invasive as an injectable filler, making it versatile in remodeling scars and healing injury sites. It is also the soft tissue type most prone to hypoxia during transplant surgeries, increasing the urgency for oxygenation therapy in this particular tissue type.