Primary Appointment Professor, Department of Biomedical Engineering
Education Ph.D., Applied Mechanics, Rensselaer Polytechnic Institute
M.S., Mechanical Engineering, Washington University
B.S., Biomedical Engineering, Rensselaer Polytechnic Institute
Classes Taught Fluid Mechanics (BE 436)
Research Areas Our lab has been engaged basic scientific research combining mathematical modeling, computational analysis, and experimental investigations ranging from macromolecular assemblies, cellular mechanics, and microscale biofluidics to cardiovascular fluid mechanics and the biomechanics of vestibular sensory systems. Our previous work in microvascular research integrated fluid dynamics with intravital microscopy to study blood flow in the microcirculation and to elucidate mechanisms by which the lining of blood vessels determines vascular health and disease. In past research, we focused on the glycocalyx, which forms a complex hydrated mesh of cell surface macromolecules that is situated at the interface between the luminal vascular wall and flowing blood. We developed new analytical and experimental tools to interrogate the glycocalyx in vivo and in vitro. We demonstrated that this layer of macromolecules retards plasma flow within ~500 nm from the vessel wall in healthy blood vessels, but is significantly degraded in the presence of vascular inflammation and chronic hyperglycemia. We also showed that the observed hydrodynamic properties of the glycocalyx in vivo are substantially absent from endothelial cells cultured under standard conditions in vitro.
Our current research is committed to creating integrated, autonomous, intelligent systems for automatically regulating blood glucose levels in diabetes and in other conditions of glycemic dysregulation. The bionic pancreas technology that we have engineered over the years was initially deployed on a laptop computer and was first tested in our lab in 2005 in a swine model of diabetes. With our clinical collaborators at the Massachusetts General Hospital (MGH), this work then progressed to in-patient trials in adults and adolescents with type 1 diabetes (T1D) from 2008–2012. From 2013–2018, our team, along with our clinical collaborators at MGH, Stanford University, the University of Massachusetts Medical School, the University of North Carolina, the University of Colorado, and Nemours Children’s Health System, conducted over a dozen outpatient and home-use clinical trials in adults and children with T1D testing a mobile version of our bihormonal bionic pancreas, which ran on an iPhone that wirelessly controlled one or two insulin pumps. More recently, our group developed a fully integrated, wearable, bionic pancreas device, which we refer to as the iLet in homage to the pancreatic islets of Langerhans that contain the alpha and beta cells that secrete glucagon and insulin. The iLet and associated technology has now been licensed to Beta Bionics, Inc., a Massachusetts Public Benefit Corporation that plans to commercialize the bionic pancreas for people with diabetes and other disorders of glycemic dysregulation. Beta Bionics recently received FDA approval to begin clinical testing of the iLet. The first home-use clinical trial of the iLet began in May 2018 in adult and pediatric volunteers with T1D. In collaboration with our lab, and 16 clinical sites across the US, Beta Bionics plans to begin final clinical trials testing the iLet in 2019 and seek FDA approval of the device for commercial distribution in the US in 2020.