Invited Seminar Series

190709 - Distinguished Seminar Series_Webpage

Joanna Aizenberg

Non-fouling medical devices: Slippery coatings that resist adhesion of biological matter

Abstract: Living organisms and biological substances are among the most difficult and persistent sources of surface fouling, particularly in medical and marine settings. The ability of organisms to adapt, move, cooperate, evolve on short timescales, and modify surfaces by secreting proteins and other molecules enables them to colonize even state-of-the-art antifouling coatings, and small surface defects can trigger protein aggregation and blood clotting. Attempts to combat these issues are further hindered by conflicting requirements at different size scales and across different species. Our recently developed concept of Slippery, Liquid-Infused Porous Surfaces (SLIPS) provides a defect-free, dynamic liquid interface that overcomes many of these problems at once. A single surface is able to prevent adhesion of a broad range of genetically diverse bacteria, including many pathogenic species that underlie widespread hospital-acquired infections. The same approach resists adhesion of proteins, cells, and blood, preventing clogging and thrombus formation inside medical tubing and catheters. We are currently developing this strategy to solve longstanding fouling issues in a wide range of medical settings. Examples described in the lecture will include the use of this material in endoscopes, medical tubing and surgical instruments.

Olivia Wang

Cross Border Investing Trends in Biomedical Engineering Start-ups

Abstract: This seminar will address the history of venture capital in technology and biology. Topics that will be discussed include: (a) Emergence of technology investing and biotechnology as separate ecosystems, how these two ecosystems are starting to merge, and what implications it has for biotechnology and healthcare start-ups, (b) Recent trend of generalist tech firms dabbling in biotechnology: Is this wise and/or sustainable?, (c) Engineering talent meets biologists - what is this new wave of software enable biology sand hill road is investing in? Additionally, profiles of biomedical engineering start-ups spun out of universities in the United States, Canada and Asia will be illustrated and the competitiveness of these companies in the global biotechnology landscape.

Fei Fei Liu

Accelerate Precision Radiation Medicine to Conquer Cancer

Abstract: Radiation therapy is a highly effective treatment for cancer. Used alone or in combination with surgery or chemotherapy, radiation therapy cure patients, control tumors, leading to improved survival and quality of life. Approximately 50% of all cancer patients will require radiation therapy as part of their treatment regimen, either to cure or to palliate disabling symptoms. The Radiation Medicine Program (RMP) at the Princess Margaret Cancer Centre is the largest single-site radiation treatment program worldwide and ranked to be amongst the top 3 such programs globally. Our vision is “Precision Radiation Medicine. Personalized Care. Global Impact”; our interdisciplinary team of physicians, medical physicists, radiation therapists and nurses supports the assessment, planning, treatment and follow-up care of patients with common, rare and complex forms of cancer.

RMP is a world leader in Radiation Medicine research aimed at developing more precise, personalized treatments to cure more patients with fewer side effects. Our research program encompasses the full spectrum of research, spanning from laboratory-based biology and physics discovery to clinical trials in patients, including survivorship, health services and education research.

Key activities will focus on six strategic areas to accelerate the availability of Adaptive Radiation Medicine for every patient. These six pillars include: a) Radiogenomics; b) Radiomics; c) MR-guided radiotherapy; d) Oligometastases; e) Regenerative radiation medicine; and f) Patient reported outcomes. These six pillars are embedded on the technological platforms of “Big Data”, and “Automation” that will serve as cross-cutting priorities which will facilitate the activities of the six pillars as outlined above.

Descriptors of each of these pillars and matrixed activities will be provided, in seeking collaborative opportunities with scientists in IBBME. Our team is committed to providing both exemplary clinical care and pushing the boundaries of scientific discovery to develop innovative radiation treatment approaches, ensuring that they are rapidly available to our own Princess Margaret patients as well as patients across Canada and around the world.

Bob Kirsch

Reconnecting the Hand and Arm to the Brain (ReHAB): BCI control of upper limb FES

Abstract: We have previously developed an implanted neuroprosthesis that uses functional electrical stimulation (FES) to activate the paralyzed muscles of the shoulder, arm, and hand in a coordinated manner to restore arm and hand function, and successfully deployed this system in three people with severe paralysis. We have more recently developed and deployed a FES system for the arm and hand that is controlled by the used via an intracortical brain-computer interface (BCI) to allow a user to direct the actions of their FES-restored arm and hand movements in an effective and intuitive manner.  This presentation will describe the performance of a 192-electrode intracortical BCI in commanding arm and hand movements in a paralyzed individual with high cervical spinal cord injury whose movements were restored by functional electrical stimulation. Our next steps in the development of BCI-controlled FES will also be presented.

Chris Contag

Micro-optical devices for the Early Detection of Cancer


Current technologies for the detection of cancer lack the sensitivity for early detection at times when therapy would be most effective, and cannot detect minimal residual disease that persists after conventional therapies. Therefore, it will be necessary to develop image-guided approaches for multiplexed molecular characterization of cancer and methods to visualize small numbers of cancer initiating cells. Imaging and sensing will need to move from detection limits of 1 cm to 1 mm, or even 100 µm diameter masses, and new technologies with this sensitivity need to be developed. Optical imaging has the sensitivity for this level of detection and there are a number of recent advances that will enable the use of optics in the clinic for cancer detection. New instruments based on micro-optical designs can be used to reach in the body to reveal microanatomic and molecular detail that are indicators of early cancers. We are advancing the technologies that enable miniaturization of 3-D scanning confocal microscopes and Raman endoscopes to examine tissue in situ for early anatomic and molecular indicators of disease, in real time, and at cellular resolution. These new devices will lead to a shift from the current diagnostic paradigm of biopsy followed by histopathology and recommended therapy, to one of non-invasive point-of-care diagnosis with the possibility of treatment in the same session. By creating the tools for point-of-care pathology we are reducing the time and distance between the patient and the diagnostic event, and changing the practice of medicine. The emerging combinations of instruments and molecular probe strategies will reveal disease states in finer detail and provide greater information to clinicians for more informed, and directed therapies. Precision medicine aims to target the molecular basis of disease, and new imaging and diagnostic tools are driving precise care and early intervention.

Lance Davidson

Lessons from the embryo: how physical mechanics shape and guide tissue self-assembly.


Watch any time-lapse of developing embryos and you will be astounded by the choreography of these self-organizing systems. Tissues coordinate their motion to generate all the multicellular forms that surround us. These motions do not only generate robust geometric forms but are also key to the physiological operation of the organism. The past 20 years have seen a resurgent interest in the role of physical mechanics that drive these movements. More recently, our group and others have been leveraging this knowledge to investigate the role that mechanical 'information' plays during development, guiding cell fate choices as well as cell behaviors. In this talk I will outline fundamental advances in biomechanics of embryonic development in the frog Xenopus laevis and then show how we are using these tools and insights to explore the mechanobiology of early development and how embryos rely on mechanical patterns to drive differentiation. I will conclude by discussing how newly exposed principles of embryonic self-assembly are leading to new insights and technologies for tissue engineering.

Mikhail Shapiro

Talking to Cells: Biomolecular Engineering for Non-Invasive Imaging and Control of Cellular Function


The study of biological function in intact organisms and the development of targeted cellular therapeutics necessitate methods to image and control cellular function in vivo. Technologies such as fluorescent proteins and optogenetics serve this purpose in small, translucent specimens, but are limited by the poor penetration of light into deeper tissues. In contrast, most non-invasive techniques such as ultrasound and magnetic resonance imaging – while based on energy forms that penetrate tissue effectively – are not effectively coupled to cellular function. Our work attempts to bridge this gap by engineering biomolecules with the appropriate physical properties to interact with magnetic fields and sound waves. In this talk, I will describe our recent development of biomolecular reporters and actuators for ultrasound and magnetic resonance imaging. The reporters are based on a unique class of gas-filled protein nanostructures from buoyant photosynthetic microbes. These proteins produce nonlinear scattering of sound waves, enabling their detection with ultrasound, and perturb magnetic fields, allowing their detection with MRI. I will describe our recent progress in understanding the biophysical and acoustic properties of these biomolecules, engineering their mechanics and targeting at the genetic level, developing methods to enhance their detection in vivo and expressing them heterologously as reporter genes. Our actuators are based on temperature-dependent transcriptional repressors, which provide switch-like control of bacterial gene expression in response to small changes in temperature. We have genetically tuned these repressors to activate at thresholds within the biomedically relevant range of 32ºC to 46ºC, and constructed genetic logic circuits to connect thermal signals to various cellular functions. This allows us to use focused ultrasound to remote-control engineered bacterial cells in vivo. In addition, we have used ultrasound in combination with viral vectors and engineered receptors to provide spatially and cell-type specific non-invasive control over neural activity.