Ravi Radhakrishnan, Professor and Chair of the Department of Bioengineering and Professor in Chemical and Biomolecular Engineering, is among the many faculty who quickly adapted their courses to an online format in the wake of the COVID-19 pandemic. Now, a recent publication in the American Institute of Chemical Engineers (AIChE) Journal reflects one of these revamped courses. The course BE 559: “Multiscale Modeling of Chemical and Biological Systems” provides theoretical, conceptual, and hands-on modeling experience on three different length and time scales: (1) electronic structure (A, ps); (2) molecular mechanics (100A, ns); and (3) deterministic and stochastic approaches for microscale systems (um, sec). During the course, students gained hands-on experience in running codes on real applications together with the following theoretical formalisms: molecular dynamics, Monte Carlo, free energy methods, deterministic and stochastic modeling. The transition to the online format was greatly facilitated by a grant from the Extreme Science and Engineering Discovery Environment (XSEDE) which provided cloud and supercomputing resources to the students facilitating the computational laboratory experience. Radhakrishnan’s article, “A survey of multiscale modeling: Foundations, historical milestones, current status, and future prospects,” reviews the foundations, historical developments, and current paradigms in multiscale modeling (MSM).
Radhakrishnan aspires to modernize computational science, integrating Multiscale Modeling and Data Science for Biological and Biomedical Science & Engineering. His team does so by integrating multiphysics modeling, computing, data science to tackle applications. The integrative approach is pictorially depicted here in terms of modeling different length and timescales using techniques such as molecular dynamics of atomistic systems, Brownian dynamics of coarse-grained systems, and field equations governing continuum scales of macroscopic systems.
César de la Fuente a Presidential Assistant Professor in the Perelman School of Medicine’s departments of Psychiatry and Microbiology and Engineering’s department of Bioengineering, has racked up accolades for his innovative, computational approach to discovering new antibiotics.
Now, in his most recent study, de la Fuente has shown how these vital drugs might be derived from wasp venom.
The study, published in The Proceedings of the National Academy of Sciences, involved altering a highly toxic small protein from a common Asian wasp species, Vespula lewisii, the Korean yellow-jacket wasp. The alterations enhanced the molecule’s ability to kill bacterial cells while greatly reducing its ability to harm human cells. In animal models, de la Fuente and his colleagues showed that this family of new antimicrobial molecules made with these alterations could protect mice from otherwise lethal bacterial infections.
There is an urgent need for new drug treatments for bacterial infections, as many circulating bacterial species have developed a resistance to older drugs. The U.S. Centers for Disease Control & Prevention has estimated that each year nearly three million Americans are infected with antibiotic-resistant microbes and more than 35,000 die of them. Globally the problem is even worse: Sepsis, an often-fatal inflammatory syndrome triggered by extensive bacterial infection, is thought to have accounted for about one in five deaths around the world as recently as 2017.
“New antibiotics are urgently needed to treat the ever-increasing number of drug-resistant infections, and venoms are an untapped source of novel potential drugs. We think that venom-derived molecules such as the ones we engineered in this study are going to be a valuable source of new antibiotics,” says de la Fuente.
De la Fuente and his team started with a small protein, or “peptide,” called mastoparan-L, a key ingredient in the venom of Vespula lewisii wasps. Mastoparan-L-containing venom is usually not dangerous to humans in the small doses delivered by wasp stings, but it is quite toxic. It destroys red blood cells, and triggers a type of allergic/inflammatory reaction that in susceptible individuals can lead to a fatal syndrome called anaphylaxis—in which blood pressure drops and breathing becomes difficult or impossible.
Mastoparan-L (mast-L) also is known for its moderate toxicity to bacterial species, making it a potential starting point for engineering new antibiotics. But there are still some unknowns, including how to enhance its anti-bacterial properties, and how to make it safe for humans.
Brian Litt, professor in Engineering’s Department of Bioengineering and the Perelman School of Medicine’s departments of Neurology and Neurosurgery, has received a five-year, $5.6 million Pioneer Award from the National Institutes of Health, which will support his research on implantable devices for monitoring, recording and responding to neural activity.
The Pioneer Award is part of the agency’s High-Risk, High-Reward Research Program honoring exceptionally creative scientists. It challenges investigators to pursue new research directions and develop groundbreaking, high-impact approaches to a broad area of biomedical or behavioral science. Litt’s neurodevice research represents a new frontier in addressing a wide variety of neurological conditions.
In epilepsy, for example, these devices would predict and prevent seizures; in Parkinson’s patients, implants will measure and communicate with patients to improve mobility, reduce tremor and enhance responsiveness. Other implants might improve hearing or psychiatric symptoms by querying patient perceptions, feelings, and altering stimulation patterns algorithmically to improve them
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.”
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?”
“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.
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.
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
The Chan Zuckerberg Initiative’s Collaborative Pairs Pilot Project Award is part of its Neurodegeneration Challenge Network
Jennifer Phillips-Cremins, Ph.D.
More than 30 inherited disorders are caused by the unstable expansion of repetitive DNA sequences, including Huntington’s disease, ALS, Fragile X syndrome, and Friedreich’s ataxia. Jennifer E. Phillips-Cremins, associate professor in Penn Engineering’s Department of Bioengineering and in the Perelman School of Medicine’s Department of Genetics, has shown another link between these disorders: the location of these expanding genes relative to the complicated folding patterns the genome exhibits to fit inside the nucleus of a cell.
Now, Phillips-Cremins is among 60 researchers taking part in a $4.5 Million Chan Zuckerberg Initiative project that aims to apply novel, interdisciplinary approaches toward investigating neurodegenerative disorders. The CZI Collaborative Pairs Pilot Project will fund 30 teams that combine clinical and basic science expertise and have at least one early- or mid-career researcher.
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.
