Emily Alexandria Waters1, Ellen Kretzschmar Kohlmeir2, Daniel J. Mastarone1, Ling-Jia Wang3, Dixon Blake Kaufman3, Thomas J. Meade1,2
1Chemistry, Northwestern University, Evanston, IL, United States; 2Biochemistry, Molecular Biology, and Cellular Biology, Northwestern University, Evanston, IL, United States; 3Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
Pancreatic islet transplant is a promising treatment for diabetes, but little is known about the fate of islets after transplant. We have developed a multimeric MR contrast agent with three macrocyclic Gd(III) chelates attached to a scaffold, with a branched alkyne chain installed to anchor the agent in cellular membranes. This agent effectively labels islets in a time- and concentration-dependent fashion. Islets can be detected with MRI after a 4h incubation with 30 μM agent. Minimal leaching occurs over a 24h period after incubation. Labeling of islets does not affect cell viability or alter islet morphology.