Matthew Weno

Type 1 diabetes is an autoimmune disease in which insulin-producing beta cells in the pancreas are attacked by T cell-mediated destruction. Patients with this chronic disorder are then unable to produce their own insulin and must utilize insulin administration to maintain normal blood sugar levels. There is currently no cure for type 1 diabetes, however current immune therapy research is focused on the use of monoclonal antibodies to lessen the burden of T1D. The antibody 1B2 binds to insulin B chain 10-23 peptide (insB) in the context of mouse major histocompatibility complex II. This study sought to determine if the antibody 1B2 could bind insB on antigen presenting cells, as well as determine what amino acids on the peptides are important to this interaction. Other antibodies including 6.9H18, and 1A1 were also included in the study, specific to 6.9 hybrid peptide and 2.5 hybrid peptide antigens respectively. It was hypothesized that 1B2 will bind bone marrow derived dendritic cells (BMDCs) pulsed with insB peptide. To test this hypothesis, BMDCs were generated from non-obese diabetic mice, pulsed with insB peptide overnight, and stained with fluorescently labeled 1B2 antibody. Using flow cytometry, we found that BMDCs pulsed with insB peptides increased fluorescence, indicative of 1B2 binding. Alanine scanning of the insB peptide determined the leucine in position 15 is important for the binding of 1B2 to BMDCs. The type of strategy used in this study could be used to characterize the biophysical properties of therapeutic antibodies.