Increased apoptosis in AD DC lymphocytes. Lymphocytes from 5 AD DC subjects and age-matched controls were examined for apoptosis by FACS. (A) Sample FACS profile of basal apoptosis for lymphocytes cultured 10 days, representing 2 AD DC subjects and 1 control. The percentage of apoptotic cells (FITC positive) is shown above the FACS histogram. (B) Summary data for 5 AD DC subjects. Basal and Fas-mediated apoptosis is expressed as percent difference of FITC gated AD DC cells relative to age-matched controls, as described in “Patients, materials, and methods.” Bold line on y axis represents control level.