Caspase-3 activity and actin polymerization response in zVAD-fmk-treated and untreated WAS lymphocytes isolated 24 hours after venipuncture.

(A, B) Activity of caspase-3 in lymphocytes isolated from whole blood that had been incubated at room temperature for 24 hours. Data are expressed as a histogram with fluorescence intensity on the x-axis and cell number on the y-axis. Mean fluorescence intensities of the control and patient lymphocyte populations were 116 and 290, respectively. Graphs are representative of data collected from a single WAS patient and a control. (C, D) Caspase-3 activity in lymphocytes isolated from whole blood (from a single patient with WAS) that had been treated for 24 hours with and without 50 μmol/L zVAD-fmk. (C) Caspase-3 activity in untreated lymphocytes. (D) Caspase-3 activity in treated cells. Note the marked decrease in fluorescence in the treated lymphocytes. Mean fluorescence intensities in untreated and zVAD-fmk–treated WAS lymphocytes were 403 and 223, respectively. Because the instrumental settings of the flow cytometer varied from day to day, these data cannot be compared directly with those shown in A and B. (E) Percentages of viable, apoptotic, and necrotic lymphocytes from WAS lymphocytes isolated from 24-hour-old blood incubated with and without 50 μmol/L zVAD-fmk as defined previously. Graphs are representative of data taken from a single WAS patient and a single control. (F) Actin polymerization response in WAS lymphocytes isolated from 24-hour-old blood incubated with and without 50 μmol/L zVAD-fmk. The actin polymerization response of WAS lymphocytes was stimulated with 100 nmol/L PMA for 40 minutes at 37°C. Error bars represent SEM of duplicate determinations from a single donor (WAS). This graph is representative of data collected from a single patient with WAS.