Safe method of collecting leukaemia cells from patients with acute leukaemia for use as immunotherapy.

Leukaemia cells were collected from the blood of 72 untreated patients using a continuous-flow blood cell separator. The yield of cells was proportional to the number circulating in the patient, and up to 1 × 10 12 could be obtained in three hours. Complications of the procedure were mild, consisting of chills and shivering in 18% of patients. Leucopheresis at the time of diagnosis is an essential part of setting up a specific immunotherapy programme for patients with acute myelogenous leukaemia, and the lack of harmful side effects makes the collection of these cells ethically justified. The need for a centralized service to provide cells for this form of therapy is emphasized.