Video 4.
MERTK signaling prevents islet T cell–APC interactions in an antigen-dependent manner. Fluorescently labeled, activated 8.3 CD8 T cells (white), BDC-2.5 CD4 T cells (red), and polyclonal T cells (blue) were cotransferred into female NOD.CD11c-YFP (green) mice. Mice were treated twice daily with saline vehicle or 30 mg/kg UNC2025, a small-molecule inhibitor of MERTK and Flt3. 16 h following the initial treatment, islets were isolated and analyzed by two-photon microscopy. Representative islet movies from vehicle- or UNC2025-treated mice with 5-min tracks of motion and circles highlighting sustained interactions between T cells and APCs. Time, minutes:seconds; scale bar, 30 µm. 6 frames/sec. Representative of data quantified in Figs. 4 and 6.