[1] UNIV UTRECHT HOSP,DEPT IMMUNOL,3508 GA UTRECHT,NETHERLANDS
[2] NETHERLANDS CANC INST,DIV IMMUNOL,1066 CX AMSTERDAM,NETHERLANDS
[3] NETHERLANDS CANC INST,DIV MOLEC GENET,1066 CX AMSTERDAM,NETHERLANDS
[4] UNIV LAUSANNE,LUDWIG INST CANC RES,CH-1066 EPALINGES,SWITZERLAND