Category: seminar

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Grace Hopper Distinguished Lecture: “Biomanufacturing Vascularized Organoids and Functional Human Tissues” (Jennifer A. Lewis)

We hope you will join us for the 2021 Grace Hopper Distinguished Lecture by Dr. Jennifer Lewis, presented by the Department of Bioengineering. For event links, email ksas@seas.upenn.edu.

Date: Thursday, March 25, 2021
Time: 3:00-4:00 PM EDT

Jennifer A. Lewis

Speaker: Jennifer A. Lewis, Sc.D.
Wyss Professor for Biologically Inspired Engineering
The Wyss Institue
Paulson School of Engineering and Applied Sciences
Harvard University

Title: “Biomanufacturing Vascularized Organoids and Functional Human Tissue”

Following the lecture, join us for a panel discussion “Horizon 2030: Engineering Life & Life in (Bio)Engineering” featuring Dr. Lewis and Penn faculty and moderated by Bioengineering students. Further details here.

Lecture Abstract:
Recent protocols in developmental biology are unlocking the potential for stem cells to undergo differentiation and self-assembly to form “mini-organs”, known as organoids. To bridge the gap from organoid building blocks (OBBs) to therapeutic functional tissues, integrative approaches that combine bottom-up organoid assembly with top-down bioprinting are needed. While it is difficult, if not impossible, to imagine how either organoids or bioprinting alone would fully replicate the complex multiscale features required for organ-specific function – their combination may provide an enabling foundation for de novo tissue manufacturing. My talk will begin by describing our recent efforts to generate organoids in vitro with perfusable microvascular networks that support their viability and maturation. Next, I will describe the generation of 3D vascularized organ-specific tissues by assembling OBBs into a living matrix that supports the embedded printing of macro-vessels by a process known as sacrificial writing in functional tissue (SWIFT).  Though broadly applicable, I will highlight our recent work on kidney, cerebral, and cardiac tissue engineering.

Dr. Lewis Bio:

Jennifer A. Lewis is the Jianming Yu Professor of Arts and Sciences, the Wyss Professor for Biologically Inspired Engineering in the Paulson School of Engineering and Applied Sciences, and a core faculty member of the Wyss Institute at Harvard University. Her research focuses on 3D printing of functional, structural, and biological materials that emulate natural systems. Prior to joining Harvard, Lewis was a faculty member in the Materials Science and Engineering Department at the University of Illinois at Urbana-Champaign, where she served as the Director of the Materials Research Laboratory. Currently, she directs the Harvard Materials Research Science and Engineering Center (MRSEC) and serves the NSF Mathematical and Physical Sciences Advisory Committee.

Lewis has received numerous awards, including the Presidential Faculty Fellow Award, the American Chemical Society Langmuir Lecture Award, the Materials Research Society Medal Award, the American Ceramic Society Sosman and Roy Lecture Awards, and the Lush Science Prize. She is an elected member of the National Academy of Sciences, National Academy of Engineering, National Academy of Inventors, and the American Academy of Arts and Sciences. Her research has enjoyed broad coverage in the popular media. To date, she has co-founded two companies, Voxel8 Inc. and Electroninks, that are commercializing technology from her lab.

Information on the Grace Hopper Lecture:
In support of its educational mission of promoting the role of all engineers in society, the School of Engineering and Applied Science presents the Grace Hopper Lecture Series. This series is intended to serve the dual purpose of recognizing successful women in engineering and of inspiring students to achieve at the highest level.
Rear Admiral Grace Hopper was a mathematician, computer scientist, systems designer and the inventor of the compiler. Her outstanding contributions to computer science benefited academia, industry and the military. In 1928 she graduated from Vassar College with a B.A. in mathematics and physics and joined the Vassar faculty. While an instructor, she continued her studies in mathematics at Yale University where she earned an M.A. in 1930 and a Ph.D. in 1934. Grace Hopper is known worldwide for her work with the first large-scale digital computer, the Navy’s Mark I. In 1949 she joined Philadelphia’s Eckert-Mauchly, founded by the builders of ENIAC, which was building UNIVAC I. Her work on compilers and on making machines understand ordinary language instructions lead ultimately to the development of the business language, COBOL. Grace Hopper served on the faculty of the Moore School for 15 years, and in 1974 received an honorary degree from the University. In support of the accomplishments of women in engineering, each department within the School invites a prominent speaker for a one or two-day visit that incorporates a public lecture, various mini-talks and opportunities to interact with undergraduate and graduate students and faculty.

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Seminar: “The Coming of Age of De Novo Protein Design” (David Baker)

David Baker, Ph.D.

Speaker: David Baker, Ph.D.
Professor
Biochemistry
University of Washington

Date: Thursday, March 18, 2021
Time: 3:00-4:00 PM EDT
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “The Coming of Age of De Novo Protein Design”

This seminar is jointly hosted by the Department of Bioengineering and the Department of Biochemistry & Biophysics.

Abstract:

Proteins mediate the critical processes of life and beautifully solve the challenges faced during the evolution of modern organisms. Our goal is to design a new generation of proteins that address current day problems not faced during evolution. In contrast to traditional protein engineering efforts, which have focused on modifying naturally occurring proteins, we design new proteins from scratch based on Anfinsen’s principle that proteins fold to their global free energy minimum. We compute amino acid sequences predicted to fold into proteins with new structures and functions, produce synthetic genes encoding these sequences, and characterize them experimentally. I will describe the de novo design of fluorescent proteins, membrane penetrating macrocycles, transmembrane protein channels, allosteric proteins that carry out logic operations, and self-assembling nanomaterials and polyhedra. I will also discuss the application of these methods to COVID-19 challenges.

Bio:

David Baker is the director of the Institute for Protein Design, a Howard Hughes Medical Institute Investigator, a professor of biochemistry and an adjunct professor of genome sciences, bioengineering, chemical engineering, computer science, and physics at the University of Washington. His research group is a world leader in protein design and protein structure prediction. He received his Ph.D. in biochemistry with Randy Schekman at the University of California, Berkeley, and did postdoctoral work in biophysics with David Agard at UCSF. Dr. Baker is a member of the National Academy of Sciences and the American Academy of Arts and Sciences. Dr. Baker is a recipient of the Breakthrough Prize in Life Sciences, Irving Sigal and Hans Neurath awards from the Protein Society, the Overton Prize from the ISCB, the Feynman Prize from the Foresight Institute, the AAAS Newcomb Cleveland Prize, the Sackler prize in biophysics, and the Centenary Award from the Biochemical society. He has also received awards from the National Science Foundation, the Beckman Foundation, and the Packard Foundation. Dr. Baker has published over 500 research papers, been granted over 100 patents, and co-founded 11 companies. Seventy-five of his mentees have gone on to independent faculty positions.

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BE Seminar: “Dissecting Multicellular Therapeutic Responses Using a Large-scale Single-cell Profiling Platform” (Siyu Chen)

Sisi Chen, Senior Research Scientist at CalTech, Pasadena, Calif. 1.23.20

Speaker: Siyu (Sisi) Chen, Ph.D.
Senior Research Scientist
Director of Beckman Institute Single-cell Profiling and Engineering Center
California Institute of Technology

Date: Thursday, February 25, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Dissecting Multicellular Therapeutic Responses Using a Large-scale Single-cell Profiling Platform”

Abstract:

Human diseases are fundamentally multicellular in nature with many different cell types contributing to disease progression and treatment response. However, how therapeutics impact each cell type in a heterogeneous population remains poorly understood because most studies are focused on isolated cell types or a handful of pathways. Now, single-cell transcriptional profiling methods allow us to collect a deep molecular portrait of the collective response of heterogeneous populations of cells to any perturbation. In my talk, I will present my research in harnessing the power of single-cell transcriptional profiling measurements to dissect therapeutic response in heterogeneous cell populations. In the first part, I will describe the probabilistic modeling framework I developed for analyzing single-cell population data across perturbations at scale (PopAlign). PopAlign models single-cell data with semantically interpretable, low-error, highly-compressed probabilistic models, which allows fast comparisons across hundreds of samples. In the second part, I will discuss how I applied this framework to analyze a drug response study of over 1.6M human primary immune cells to 500 commercially-available immunomodulatory compounds. While most compounds in the library exert broad impact across multiple cell types in the population, my analysis also reveals highly cell-type specific activity, including a novel myeloid-suppressing function of a group of compounds including NSAIDs and an artificial sweetener. My work provides new depth and insight into how existing compounds reshape immune populations, and a general platform for evaluating and designing population-level responses to therapeutic interventions.

Bio:

Sisi Chen is a Senior Research Scientist and the Director of the Beckman Single-cell Profiling and Engineering Center (SPEC) at Caltech, where she leads a team focused on single-cell technology development. She completed her B.S. in Electrical Engineering at MIT, and her Ph.D. in Bioengineering at UC-Berkeley/UCSF, where she was an NSF and NDSEG fellow working on microfluidic tools for single-cell biology. Most recently, she has developed a computational platform to analyze single-cell transcriptional data at large-scale, and has used this platform to map human immune system responses to hundreds of small molecule immunomodulatory compounds. Her research blends experimental and computational approaches to learning and controlling the collective response of multicellular tissues to therapeutic interventions.

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BE Seminar: “Engineering Synthetic Biomaterials for Islet Transplantation” (María M. Coronel)

Speaker: María M. Coronel, Ph.D.
Postdoctoral Fellow, the George W. Woodruff School of Mechanical Engineering
Georgia Institute of Technology

Date: Thursday, February 18, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Engineering Synthetic Biomaterials for Islet Transplantation”

Abstract:

Two major challenges to the translation of cellular-based tissue-engineered therapies are the lack of adequate oxygen support post-implantation and the need for systemic immunosuppression to halt the strong inflammatory and immunological response of the host. As such, strategies that aim at addressing oxygen demand, and local immunological responses can be highly beneficial in the translation of these therapies. In this seminar, I will focus on two biomaterial strategies to create a more favorable transplant niche for pancreatic islet transplantation. The first half will describe an in-situ oxygen-releasing biomaterial fabricated through the incorporation of solid peroxides in a silicone polymer. The implementation of this localized, controlled and sustained oxygen-generator mitigates the activation of detrimental hypoxia-induced pathways in islets and enhances the potency of extrahepatic 3D islet-loaded devices in a diabetic animal model. In the second part, I will focus on engineering synthetic biomaterials for the delivery of immunomodulatory signals for transplant acceptance. Biomaterial carriers fabricated with polyethylene glycol microgels are used to deliver immunomodulatory signals to regulate the local microenvironment and prevent allograft rejection in a clinically relevant pre-clinical transplant model. The use of synthetic materials as an off-the-shelf platform, without the need for manipulating the biological cell product, improves the clinical translatability of this engineered approach. Designing safer, responsive biomaterials to boost the delivery of targeted therapeutics will significantly reinvigorate interventional cell-based tissue-engineered therapies.

Bio:

Dr. María M. Coronel is currently a Juvenile Diabetes Research Foundation postdoctoral fellow at the Georgia Institute of Technology. Dr. Coronel completed her BS degree in Biomedical Engineering from the University of Miami, and her Ph.D. degree in Biomedical Engineering from the University of Florida as a National Institute of Health predoctoral fellow. Her doctoral work focused on engineering oxygen-generating materials for addressing the universal challenge of hypoxia within three-dimensional tissue-engineered implants. As a postdoctoral fellow, her research interest focus on engineering tools and principles to understand, stimulate, and modulate the immune system to develop controlled targeted interventional therapies. In addition to research, Dr. Coronel aims to be an advocate for diversity and inclusion in STEM as the co-president of the postdoctoral group and a founding member of the diversity, equity, and inclusion committee in bioengineering at Georgia Tech. Outside of the lab María enjoys cooking, baking, and traveling.

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BE Seminar: “Multi-input Chemical Control with Computationally Designed Proteins for Research Tools and Cell Therapies” (Glenna Wink Foight)

Speaker: Glenna Wink Foight, Ph.D.
Senior Scientist
Lyell Immunopharma

Date: Thursday, February 11, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Multi-input Chemical Control with Computationally Designed Proteins for Research Tools and Cell Therapies”

Abstract:

Protein modules that are responsive to small molecule inputs have enabled control of cellular processes for decades’ worth of important mechanistic studies. More recently, they have gained attention as a means of control for improved safety of cellular therapies. To date, most small molecule-responsive systems have been adapted from natural proteins, which provide limited control behaviors and often rely on small molecules with non-ideal properties for use in humans. I will describe how we have used computational protein design to move beyond these naturally occurring systems to create a new set of molecular tools that are responsive to multiple clinically approved drugs. The unique architecture of our system enables more complex control behaviors for multiple cellular outputs. I will describe applications of this designed system in the control of mammalian cytoskeletal signaling, transcription, and CAR T-cell therapy.

Bio:

Dr. Glenna Foight is a Senior Scientist at Outpace Bio, where she leads a team that focuses on engineering small molecule drug-based control of cell therapies. Her work at the startups Outpace Bio and Lyell Immunopharma has involved the adaptation of technologies that she developed as a Washington Research Foundation Innovation Postdoctoral Fellow at the University of Washington. Dr. Foight received her Ph.D. in Biology from MIT and her B.S. in Biochemistry from North Carolina State University. Her background is in applying protein design and engineering to develop novel molecular interventions and control strategies for applications in basic research, cancer, and cell therapy.

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BE/MEAM Seminar: “Microbes in Biomechanics” (Christopher J. Hernandez)

Speaker: Christopher J. Hernandez, Ph.D.
Professor, Sibley School of Mechanical and Aerospace Engineering, Cornell University
Adjunct Scientist, Hospital for Special Surgery

Date: Thursday, February 4, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Microbes in Biomechanics”

This seminar is jointly hosted by the Department of Bioengineering and the Department of Mechanical Engineering and Applied Mechanics.

Abstract:

The idea that mechanical stresses influence the growth and form of organs and organisms originated in the 1800s and is the basis for the modern study of biomechanics and mechanobiology. Biomechanics and mechanobiology are well studied in eukaryotic systems, yet eukaryotes represent only a small portion of the diversity and abundance of life on Earth. Bacteria exhibit broad influences on human health (as both pathogens and as beneficial components of the gut microbiome) and processes used in biotechnology and synthetic biology. Over the past eight years my group has explored mechanobiology within individual bacteria and the effects of changes in the composition of commensal bacterial communities on the biomechanics in the musculoskeletal system.

The ability of the bacteria to not only resist mechanical loads (biomechanics) but also to respond to changes in the mechanical environment (mechanobiology) is necessary for survival. Here I describe a novel microfluidic platform used to explore the biomechanics and mechanobiology of individual, live bacteria. I discuss work from my group demonstrating that mechanical stress within the bacterial cell envelope can influence the assembly and function of multicomponent efflux pumps used by bacteria to resist toxins and antibiotics. Additionally, I share some of our more recent work showing that mechanical stress and strain within the bacterial cell envelope can stimulate a bacterial two-component system controlling gene expression. Our findings demonstrate that bacteria, like mammalian cells, have mechanosensitive systems that are key to survival.

In musculoskeletal disease, bacteria are commonly viewed as sources of infection. However, in the past decade the studies by my group and others have suggested that commensal bacteria – the microbiome – can modulate the pathogenesis of musculoskeletal disorders. My group is among the first to study the effects of the gut microbiome on orthopaedic disorders. Here I provide an introduction to the microbiome and current concepts of how modifications to the gut microbiome could influence the musculoskeletal system. Specifically, I discuss studies from my group which are the first to demonstrate that the gut microbiome influences bone biomechanics and the development of infection of orthopaedic implants.

Bio:

Dr. Hernandez is Professor in the Sibley School of Mechanical and Aerospace Engineering at Cornell University and is an Adjunct Scientist at the Hospital for Special Surgery. Dr. Hernandez is a Fellow of the American Institute for Medical and Biological Engineering (AIMBE), the American Society of Mechanical Engineers (ASME), and the American Society for Bone and Mineral Research (ASBMR). He is the 2018 recipient of the Fuller Albright Award for Scientific Excellence from the American Society for Bone and Mineral Research. He has served on the Board of Directors of the Orthopaedic Research Society and the American Society for Bone and Mineral Research. His laboratory’s research currently focuses on the effects of the microbiome on bone and joint disorders, periprosthetic joint infection and the biomechanics and mechanobiology of bacteria.

hernandezresearch.com

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BE Seminar: “Designing Biology for Detection and Control” (Pamela A. Silver)

Speaker: Pamela A. Silver, Ph.D.
Elliot T. and Onie H. Adams Professor of Biochemistry and Systems Biology
Harvard Medical School

Date: Thursday, January 28, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Designing Biology for Detection and Control”

Abstract:

The engineering of Biology presents infinite opportunities for therapeutic design, diagnosis, and prevention of disease. We use what we know from Nature to engineer systems with predictable behaviors. We also seek to discover new natural strategies to then re-engineer. I will present concepts and experiments that address how we approach these problems in a systematic way. Conceptually, we seek to both design cells and proteins to control disease states and to detect and predict the severity of emerging pathogens. For example, we have engineered components of the gut microbiome to act therapeutics for infectious disease, proteins to prolong cell states, living pathogen sensors and high throughput analysis to predict immune response of emerging viruses.

Bio:

Pamela Silver is the Adams Professor of Biochemistry and Systems Biology at Harvard Medical School and the Wyss Institute for Biologically Inspired Engineering. She received her BS in Chemistry and PhD in Biochemistry from the University of California. Her work has been recognized by an Established Investigator of the American Heart Association, a Research Scholar of the March of Dimes, an NSF Presidential Young Investigator Award, Claudia Adams Barr Investigator, an NIH MERIT award, the Philosophical Society Lecture, a Fellow of the Radcliffe Institute, and election to the American Academy of Arts and Sciences. She is among the top global influencers in Synthetic Biology and her work was named one of the top 10 breakthroughs by the World Economic Forum. She serves on the board of the Internationally Genetics Engineering Machines (iGEM) Competition and is member of the National Science Advisory Board for Biosecurity. She has led numerous projects for ARPA-E, iARPA and DARPA. She is the co-founder of several Biotech companies including most recently KulaBio and serves on numerous public and private advisory boards.

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BE Seminar: “Deconstructing and Reconstructing Human Tissues” (Kelly Stevens)

Kelly Stevens, PhD

Speaker:  Kelly Stevens, Ph.D.
Assistant Professor, Department of Bioengineering and Department of Laboratory Medicine & Pathology
University of Washington

Date: Thursday, January 21, 2021
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Deconstructing and Reconstructing Human Tissues”

Abstract:

Although much progress has been made in building artificial human tissues over the past several decades, replicating complex tissue structure remains an enormous challenge. To overcome this challenge, our field first needs to create better three-dimensional spatial maps, or “blueprints” of human tissues and organs. We also need to then understand how these spatial blueprints encode positional processes in tissues. My group is developing new advanced biofabrication technologies to address both of these issues. Here, I will describe some of our work in both attaining transcriptomic maps as well as in controlling spatiogenetic wiring of human artificial tissues.

Bio:

Dr. Kelly Stevens is an Assistant Professor of Bioengineering, and Laboratory Medicine & Pathology at the University of Washington. Dr. Stevens’ research focuses on mapping and building artificial human tissues to treat liver and heart disease. She has made contributions to improve human cell sourcing, vascularization, structure and physiology of human bioartificial tissues. Dr. Stevens has received several awards in recognition of this work, including the NIH New Innovator Award, BMES CMBE Rising Star Award, John Tietze Stem Cell Scientist Award, and Gree Foundation Scholar Award.

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BE Seminar: “Emerging Technologies for Detection of Early Stage Bladder Cancer” (Audrey Bowden)

Audrey Bowden, PhD, Associate Professor of Biomedical Engineering. (Vanderbilt University / Steve Green)

Speaker: Audrey Bowden, Ph.D.
Dorothy J. Wingfield Phillips Chancellor’s Faculty Fellow and Associate Professor of Biomedical Engineering and Electrical Engineering & Computer Science
Vanderbilt University

Date: Thursday, November 19, 2020
Time: 3:00-4:00 PM EST
Zoom – check email for link or contact ksas@seas.upenn.edu

Title: “Emerging Technologies for Detection of Early Stage Bladder Cancer”

Abstract:

Bladder cancer (BC) —  the 4th most common cancer in men and the most expensive cancer to treat over a patient’s lifetime — is a lifelong burden to BC patients and a significant economic burden to the U.S. healthcare system. The high cost of BC stems largely from its high recurrence rate (>50%); hence, BC management involves frequent surveillance. Unfortunately, the current in-office standard-of-care tool for BC surveillance, white light cystoscopy (WLC), is limited by low sensitivity and specificity for carcinoma in situ (CIS), a high-grade carcinoma with high potential to metastasize. Early detection and complete eradication of CIS are critical to improve treatment outcomes and to minimize recurrence. The most promising macroscopic technique to improve sensitivity to CIS detection, blue light cystoscopy (BLC), is costly, time-intensive, has low availability and a high false-positive rate. Given the limitations of WLC, we aim to change the paradigm around how BC surveillance is performed by validating new tools with high sensitivity and specificity for CIS that are appropriate for in-office use. In this seminar, I discuss our innovative solutions to improve mapping the bladder for longitudinal tracking of suspicious lesions and to create miniature tools for optical detection based on optical coherence tomography (OCT). OCT and its functional variant, cross-polarized OCT, can detect early-stage BC with better sensitivity and specificity than WLC. We discuss the critical technical innovations necessary to make OCT and CP-OCT a practical tool for in-office use, and new results from recent explorations of human bladder samples that speak to the promise of this approach to change the management of patient care.

Bio:

Audrey K. Bowden is the Dorothy J. Wingfield Phillips Chancellor Faculty Fellow and Associate Professor of Biomedical Engineering (BME) and of Electrical Engineering and Computer Science (EECS) at Vanderbilt University. Prior to this, she served as Assistant and later Associate Professor of Electrical Engineering and Bioengineering at Stanford University. Dr. Bowden received her BSE in Electrical Engineering from Princeton University, her PhD in BME from Duke University and completed her postdoctoral training in Chemistry and Chemical Biology at Harvard University. During her career, Dr. Bowden served as an International Fellow at Ngee Ann Polytechnic in Singapore. From 2007-2008, she was the Arthur H. Guenther Congressional Fellow sponsored by the OSA and SPIE and served as a Legislative Assistant in the United States Senate through the AAAS Science and Technology Policy Fellows Program. Dr. Bowden is a Fellow of SPIE, a Fellow of AIMBE and is the recipient of numerous awards, including the Air Force Young Investigator Award, the NSF Career Award, the Hellman Faculty Scholars Award, the Phi Beta Kappa Teaching Award, Ford Foundation Postdoctoral Fellowship, and the NSBE Golden Torch Award. She is a former Associate Editor of IEEE Photonics Journal, former Lead Guest Editor of a Biomedical Optics Express Special Issue and is a member of numerous professional committees. Her research interests include biomedical optics – particularly optical coherence tomography and near infrared spectroscopy – microfluidics, and point of care diagnostics.

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Neuroengineering/Bioengineering Seminar: “Photovoltaic Restoration of Sight in Age-related Macular Degeneration” (Daniel Palanker)

Daniel Palanker, PhD

The Center for Neuroengineering and Therapeutics and the Department of Bioengineering present:

Speaker: Daniel Palanker, Ph.D.
Director of the Hansen Experimental Physics Laboratory and Professor of Ophthalmology
Stanford University

Date: Wednesday, November 18, 2020
Time: 1:00-2:00 PM EST
Zoom – check email for link or contact eprince@seas.upenn.edu

Title: “Photovoltaic Restoration of Sight in Age-related Macular Degeneration”

Abstract:

Retinal degenerative diseases lead to blindness due to loss of the “image capturing” photoreceptors, while neurons in the “image-processing” inner retinal layers are relatively well preserved. Information can be reintroduced into the visual system using electrical stimulation of the surviving inner retinal neurons. We developed a photovoltaic substitute of photoreceptors which convert light into pulsed electric current, stimulating the secondary retinal neurons. Visual information captured by a camera is projected onto the retina from augmented-reality glasses using pulsed near-infrared (~880nm) light. This design avoids the use of bulky electronics and wiring, thereby greatly reducing the surgical complexity. Optical activation of the photovoltaic pixels allows scaling the number of electrodes to thousands. In preclinical studies, we found that prosthetic vision with subretinal implants preserves many features of natural vision, including flicker fusion at high frequencies (>30 Hz), adaptation to static images, antagonistic center-surround organization and non-linear summation of subunits in receptive fields, providing high spatial resolution. Results of the clinical trial with our implants (PRIMA, Pixium Vision) having 100μm pixels, as well as preclinical measurements with 75 and 55μm pixels, confirm that spatial resolution of prosthetic vision can reach the pixel pitch. Remarkably, central prosthetic vision in AMD patients can be perceived simultaneously with peripheral natural vision. For broader acceptance of this technology by patients who lost central vision due to agerelated macular degeneration, visual acuity should exceed 20/100, which requires pixels smaller than 25μm. I will describe the fundamental limitations in electro-neural interfaces and 3-dimensional configurations which should enable such a high spatial resolution. Ease of implantation of these wireless arrays, combined with high resolution opens the door to highly functional restoration of sight.

Bio:

Daniel Palanker is a Professor of Ophthalmology and Director of the Hansen Experimental Physics Laboratory at Stanford University. He received MSc in Physics in 1984 from the State University of Armenia in Yerevan, and PhD in Applied Physics in 1994 from the Hebrew University of Jerusalem, Israel. Dr. Palanker studies interactions of electrical field with biological cells and tissues, and develops optical and electronic technologies for diagnostic, therapeutic, surgical and prosthetic applications, primarily in ophthalmology. In the range of optical frequencies, his studies include laser-tissue interactions with applications to ocular therapy and surgery, and interferometric imaging of neural signals. In the field of electro-neural interfaces, he is developing highresolution photovoltaic retinal prosthesis for restoration of sight and implants for electronic control of organs. Several of his developments are in clinical practice world-wide: Pulsed Electron Avalanche Knife (PEAK PlasmaBlade, Medtronic), Patterened Scanning Laser Photocoagulator (PASCAL, Topcon), Femtosecond Laser-assisted Cataract Surgery (Catalys, J&J), and Neural Stimulator for enhancement of tear secretion (TrueTear, Allergan). Photovoltaic retinal prosthesis for restoration of sight (PRIMA, Pixium Vision) is in clinical trials.

See the full list of upcoming Penn Bioengineering events here.