ASML-exosomes and T cell migration. T cells were stimulated as indicated for 24 h. (A-C) Stimulated T cells were seeded in RPMI/1%FCS in the upper part of a Boyden chamber, the lower part contained RPMI/20%FCS. Where indicated, T cells stimulated in the presence of ASML-exosomes were washed, evaluating migration in the absence of ASML-exosomes. The percentage of migrating cells was evaluated after 4 h at 37°C. (B) T cells were stimulated for 24 h with PMA. Before migration, cells were incubated with the indicated antibodies (30 min, 4°C). (C) T cells were stimulated, washed and incubated with the indicated antibodies (30 min, 4°C). Migration was evaluated in the presence/absence of ASML-exosomes. (A-C) Mean percent ± SD (triplicates, 3 experiments) of migrating cells. (A) Significant differences in cultures containing or pre-incubated with ASML-exosomes: *, (B,C) significant antibody inhibition: *, (C) significant inhibition in the presence of ASML-exosomes: s. (D) Migration-related signaling molecule including SDF1 and CXCR4 expression was evaluated by flow-cytometry. Mean percent ± SD (3 experiments) of stained cells, significant differences in cultures containing ASML-exosomes: *. Tumor-exosomes affect T cell migration. This is due to a blockade of migration-relevant adhesion molecules engaged in exosome uptake. Up-taken exosomes hardly affect T cell migration.