Autologous bone marrow transplantation for B cell malignancies after in vitro purging with floating immunobeads
Stoppa, A.M.; Hirn, J.; Blaise, D.; Delaage, M.; Novakovitch, G.; Viens, P.; Capiello, M.A.; Mannoni, P.; Mawas, C.; Maraninchi, D.
Bone Marrow Transplantation 6(5): 301-307
1990
ISSN/ISBN: 0268-3369 PMID: 2291992 Document Number: 355435
We report here 16 autologous bone marrow transplantations (ABMT) for poor prognosis B or pre-B malignancies (16 acute lymphoblastic leukemias (ALL), three Burkitt lymphomas, one multiple myeloma) in 11 adults and five children where in vitro purging was accomplished by means of floating immunobeads. This method was developed to avoid non-specific killing by complement or toxin or batch-to-batch variability and provides a 3 log reduction of tumor in a model of B lymphoid malignancies. Low density bone marrow mononuclear cells were incubated for 30 min at 4.degree. C with anti CD10 (ALB2 Immunotech) and/or anti CD19 (Bg4) monoclonal antibodies (MoAb) and then mixed with low density polypropylene beads precoated with a rat antimouse MoAb. After 1 h at 4.degree. C the beads with target cells were decanted; the depleted marrow was collected through a microfilter and cryopreserved. After immunodepletion the recovery of nucleated cells was 75% with a median of 0.75 .times. 108 cells/kg (range 0.3-3.6) and the recovery of hematopoietic progenitors was 83% with a median of 2.9 .times. 104 CFU-GM/kg. The conditioning regimen consisted of busulfan 16 mg/kg and melphalan 140 mg/m2 for three patients, fractionated total body irradiation (TBI) following melphalan 140 mg/m2 for nine patients, TBI and cyclophosphamide 120 mg/m2 for two patients and TBI associated with melphalan and cyclophosphamide for two patients. The median time to achieve neutrophil counts > 100, 500 and 1000 .times. 106/l were 9 days (range 6-16), 14 days (range 8-30) and 22 days (range 11-40) respectively. The median times to achieve platelet counts > 20 and 50 .times. 109/l were 20 days (range 6-60) and 35 days (range 16-90) respectively. These results show that the use of floating immunobeads is a simple, rapid and safe technique to remove B cells before ABMT and avoids the limitation of the complement lysis model.