AICD of lymphocytes with cytotoxic-granule deficiencies. (A) CHQ sensitivity of AICD of lymphocytes from Rab-27a (GS)– and perforin (FLH)–deficient patients was compared with those of ALPS-I and CT. TSST-1 T-cell blasts were restimulated with soluble TSST-1 (■) during 6 hours in the presence of CHQ (▨), compared with Fas-induced cell death (□). (n = 2 for CT and GS; P3 and FLH were tested once). (B) Day 9 TSST-1 T-cell blasts were stimulated 30 minutes with soluble TSST-1, and then conjugates were analyzed. Cytotoxic granules were visualized by FITC-labeled anti-perforin deltaG9 mAb (green). Nuclei were labeled with DAPI dye (blue) and CD8⁺ cells were stained with anti-CD8 APC (red). CD4⁺ T cells were left unlabeled. Representative images from 2 independent experiments are shown. Scale bars represent 5 μm. In all conditions except FLH, all observed conjugates are formed with at least one cell polarizing perforin-containing granules. The number of conjugates observed is not significantly different in the 5 conditions tested (mean = 49% ± 5% [SEM]).