Romario Regeenes (MASc): Design of a Multiparameter Islet-on-a-chip Device to Measure the Functional Variability of Individual Pancreatic Islets

October 18, 2017 @ 9:30 am – 10:00 am
Rosebrugh Building
Rosebrugh Bldg, Toronto, ON M5S 3G9

Room: RS 211


Type 1 diabetes results from a loss of beta-cell mass due to autoimmune destruction. Currently, islet transplantation offers treatment to a limited number of patients but due to a limited supply of donor islets this treatment will never be universally available. Thus, engineering beta-cell tissue for transplantation would provide an opportunity to treat many more people. However, the success will depend heavily on tissue quality. To help inform the design of beta-cell tissue, we are creating a microfluidic device to assay multiple readouts of function. First, we aim to measure C-peptide release as a proxy for endogenous insulin. This will be done by creating an on-chip competition assay based on C-peptide conjugated to 5-TAMRA and changes in fluorescence anisotropy. Second, we are interested in measuring oxygen consumption rates of individual islets. Oxygen is a major contributor to the electron transport chain and can be used to identify perturbations in oxidative phosphorylation. We are using RuII(bpy)3 as an optical sensor to measure oxygen. The oxygen sensitive dye will serve as a seed layer on the base of the device. Lastly, we are interested in measuring the extracellular acidification rate as a readout of glycolytic rate and/or oxidative phosphorylation. We will use HPTS, a pH sensitive dye, in solution. Each of these sensors are spectrally and/or spatially resolved. This strategy will allow us to simultaneously measure these responses in a single islet. This multiparametric characterization will allow us to inform on the production of engineered islets as well as screen the tissue prior to transplantation.