T cells from CLL patients exhibit impaired LFA-1 – mediated motility that can be induced in healthy T cells via direct tumor cell contact. (A) Phase-contrast images (original magnification ×20) of primary T cells isolated from age-matched healthy donors (top) and CLL patients (bottom) were allowed to adhere to immobilized CD54 ligand for 10 minutes following exposure to chemokine CXCL12. (B) Video microscopy was then used to observe the migration of (Bi) CD4 or (Bii) CD8 T cells on CD54 for 20 minutes before the migration of individual cells was tracked. Representative migratory tracks of individual T cells from healthy donors compared with those of CLL patients are shown in the upper plots (n = 40 cells per patient experiment). Box-and-whisker plots of 14 independent CLL patient migration experiments are shown in the bottom box plots. (Ci) The image shows a schematic summary of 2-part coculture functional assays. Healthy donor CD3 T cells were cocultured (48 hours) with either CLL cells (untreated or pretreated with an anti-CD54 neutralizing mAb to block CLL/T cell contact) or third-party healthy B cells (control), and then purified for subsequent migration assay analysis on CD54. (Cii) Box-and-whisker plot analysis of 14 independent CLL patient migration experiments is shown. **P < .01. ns, nonsignificant findings.