Antileukemia CTLp frequency in AML patients treated with chemotherapy. Antileukemia CTLp frequencies were evaluated in PBMCs obtained approximately 3 months (▦), 6 months (▩), and 12 months (▪) after diagnosis. In patient 1 antileukemia CTLp frequency was evaluated also 30 months after the diagnosis (□). Results are expressed as number of CTLp's for 10⁶ cells. Patients 2, 3, and 4 experienced leukemia relapse (see Table 1 and “Results”).