Fig. 5.

Guidance of lung-infiltrating T cells along the vasculature. GFP⁺ effector T cells were injected i.v. into LPS-treated mice. After two to five days, the vasculature was labeled intravitally by intravenous injection of fluorescently labeled lectin. Two-photon imaging of explanted lungs enabled simultaneous visualization of GFP⁺ T cells and the vasculature. a–c High-resolution images of vascular stain of live lung tissue (left panels) with superimposed T cell trajectories (right panels). Tracks that are apparently aligned with the vasculature are highlighted in green. Scale bars = 20 µm. d Tracks were split into 24 µm wide segments (n = 414 segments from ten movies). For each experimental segment, a randomized control segment was generated. An alignment angle, between segments and the main orientation of the vasculature, was calculated for all experimental and randomized segments. The Mann–Whitney test was used to calculated P-values for comparison of alignment angles from experimental and randomized segments. e High-resolution image of lung region displaying adoptively transferred T cells (in green) and lung vasculature (in red). The blue dotted line and the green solid line indicate tracks of two distinct T cells. Scale bar = 20 µm