Figure 1. CLL patients have impaired T cell immune synapse formation.

(A) T cell conjugates formed between T cells from CLL patients or age-matched healthy donors and sAg-pulsed autologous CLL B cells or healthy B cells, respectively, were scored by visual counting using a confocal microscope. Each data set shows the mean ± SD from 6 independent experiments, with 50 random T cells analyzed per experiment. (B) Autologous conjugate experiments were performed as in A, comparing CLL patients with low (less than 20 mm³) absolute wbc versus high wbc (20 mm³ or more) with age-matched healthy donor cell conjugates. Each data set shows the mean ± SD from 3 independent experiments, with 50 random T cells analyzed per experiment. (C) T cells from CLL patients or age-matched healthy donors were allowed to conjugate with autologous CLL cells or healthy B cells, respectively, with or without sAg (blue, CMAC dyed). Conjugates were then fixed and stained with rhodamine phalloidin to detect F-actin (red). Note the lack of F-actin enrichment at the synapse site in T cells from CLL even in the presence of sAg-pulsed CLL cells. Original magnification, ×63. (D) Conjugates were selected at random for imaging and were scored for accumulation of F-actin at the immune synapse. Each data set shows the mean ± SD from 9 independent patient experiments, with 50 conjugates analyzed per experiment.