“…There is recent evidence for a malignant contamination of most of the blood cell grafts (Bird et al, 1994;Lambrechts et al, 1993). Therefore further reducing the quantity of contaminating tumour cells is necessary, methods targeting the CD34 antigen expressed on haemopoietic progenitors, but not on NHL and MM malignant cells (Berenson et al, 1987;Vescio et al, 1994), enable isolation of haemopoietic PBPC and should result in tumour cell depletion (Shpall et al, 1994;Gorin et al, 1995). Previous studies demonstrated that CD34 cells isolated by a biotinavidin immunoadsorption method were capable of reconstituting haemopoiesis in patients with solid cancers (Shpall et al, 1994;Brugger, 1994) and NHL (Gorin et al, 1995).…”