Materials and Reagents

1. Target cells: Acute Myeloid Leukemia (AML) cell line (U937 or HL60 from ATCC) or AML cells isolated from patients with AML
   
2. Effector cells: γδ T cells isolated from Healthy volunteer provided by Etablissement
   
3. Francais du Sang (EFS) or patients
   
4. Medium : RPMI 1640 (Life Technologies, Gibco^®)
   
5. Fetal Calf Serum (FCS) heat-inactivated 1 h at 56 °C
   
6. Chromium-51 (⁵¹Cr, 5 mCi/ml) (PerkinElmer)
   
7. Complete medium = RPMI 1640 medium supplemented with 10% heat-inactivated FCS
   

Equipment

1. Centrifuge for microplates
   
2. Microplates (96 well round-bottom) for cell incubations
   
3. LumaPlate^TM (PerkinElmer)
   
4. Liquid scintillation counter
   
5. Incubator
   

Controls

1. Spontaneous Release: Target cells were incubated alone (replace effector cells by 50 μl of media). After 4 h of incubation, wells were centrifuged and 50 μl of supernatant were recovered.
   
2. Maximum load: Target cells were incubated alone (replace effector cells by 50 μl of media). After 4 h of incubation, wells were mixed and 50 μl of cell suspension were recovered rather than disrupt the cell membrane to release the radioactivity into the supernatant). This avoids the use of detergent.
   

Procedure