Briefly, a minimum
of 4 X i03 CTLL cells were plated in microtiter wells with duplicate
dilutions ofeither experimental supernatants or recombinant
IL-2 (r-IL-2, Amersham) and were incubated at 37 #{176}C
for 24 h. After a 4-h pulse with [3H]thymidine (Amersham),
incorporation was calculated as dpm on a liquid-scintillation
counter (LKB-Wallac, Fisher Scientific, Montreal).