Figure 4: Dynamics of Tregs during antigen-specific Tconv priming.
From: Imaging regulatory T cell dynamics and CTLA4-mediated suppression of T cell priming
(a) Experimental design to examine endogenous Treg behaviour during an immune response. Ova-pulsed DCs were adoptively transferred into Foxp3EGFP mice 24 h prior to transfer of CMTMR-labelled OTII Tconv cells; imaging was performed 12 h after OTII T-cell transfer. (b) Tconv-DC clusters. Still image showing DCs (blue), OTII Tconv cells (red) and Tregs (green). Scale bar, 50 μm, see Supplementary Video 8. (c) Tconv and Treg velocities. Mean track velocities of OTII T cells were separated into those that interacted with a DC (DC+ OTII, n=99) and those that did not (DC− OTII, n=426). Treg velocities, n=811. Data are pooled from three experiments. (d) Contact history map for 14 representative Tregs. Each horizontal bar represents time when a single Treg was alone (grey), in contact with a Tconv (red), in contact with a DC (blue) or in contact with DC:Tconv pairs (green). (e) Close-up images of Treg–Tconv-cell contacts (white arrows) in the vicinity of a DC. The panel shows three-way rotations at two time points, 67 s apart. Scale bar, 10 μm.
