Fig. 1.
CD4+ Th17 cells directly contact oligodendrocytes in EAE. EAE was induced in C57BL/6-CNP-Cre × C57BL/6.loxp.ROSA.tdRFP (CNPtdRFP) recipient mice by the transfer of fluorescent myelin-reactivated Th17-skewed cells (C57BL/6 or 2D2 GFP or CFP cells). In vivo two-photon laser scanning microscopy was performed in the upper brainstem 2 to 3 d after EAE symptom onset (score around 2.0 to 2.5). (A) Visualization of oligodendrocytes (red) and T cells (green) over a period of 60 min. (B) Visualization of surface reconstructed images of an oligodendrocyte (red)–T cell (green) interaction from four different angles. (Scale bar, 10 µm.) (C) Visualization of surface reconstructed images of a T cell (green) interacting with different oligodendrocyte (red) areas. (D) Quantification of the contact duration between T cells and oligodendrocytea. n = 49 cells from four different mice, one movie per mouse. Blue vertical lines mark 5 min and 10 min contact duration; horizontal arrows represent the range of duration of contact beginning with 5 or 10 min. (E) Quantification of the number of distinct oligodendrocyte areas a T cell is interacting with in a period of up to 73 min. n = 49 cells from four different mice, one movie per mouse. (F) Quantification of T cell interaction types. (G) Representative examples of T cell tracks (mean track velocity) for a stable contact and a scanning behavior over time. (H) Comparison of meandering index, mean speed, and arrest coefficient between T cells showing no significant contact, scanning behavior including long-lasting (>5 min) contacts, and stable contacts (≥10 min). n = 88 cells from seven different mice, one movie per mouse. Statistical analysis for H was performed using one-way ANOVA with Tukey’s post hoc test. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001.