Figure 5
CLL T cells have reduced activation and effector function.
(A) Healthy CD8+ and CD4+ T cells were cocultured for 48 h as described in Figure 4. T cell conjugates formed during 5 min were fixed, permeabilized, and stained with anti-phosphotyrosine Ab (green) and rhodamine phalloidin (red). Quantitative image analysis (relative recruitment index [RRI]) of phosphotyrosine accumulation at the immunological synapse is shown, representative of evaluation of 150 conjugates from 3 independent experiments (50 conjugates analyzed per experiment), with the mean value shown as a black bar. Original magnification, ×63. (B) Healthy CD3+ T cells were first cocultured in direct contact with allogeneic healthy B cells or 3 different CLL B cells (CLL 1-3) with the addition of anti–ICAM-1 monoclonal antibody or isotype control IgG, and then were used in secondary MLRs with third-party allogeneic PBMCs as stimulators. [3H]-thymidine incorporation was assessed for the last 16 h of a 3-d culture. The stimulation index was calculated as cpm of T cells with stimulator cells/cpm of T cells alone. Results are the mean stimulation index ± SD from 5 independent healthy donor CD3+ T cells. IL-2 was assessed by ELISA, and values represent the mean ± SD from 5 independent healthy donor CD3+ T cells tested. (C) HLA-A*0201–expressing CD8+ cells were stimulated in vitro with DCs pulsed with immunoglobulin heavy chain–derived (IgVH-derived) peptide TLYLQMNSL weekly for 4 wk, and killing of peptide-pulsed H2 cells was assessed at the effector/target ratios shown. The results are the mean ± SD from 6 independent CLL patient and healthy donor experiments.
