Autologous bone marrow transplantation after in vitro purging with bcr/abl antisense for CML

bcr/abl antisense oligodeoxynucleotides(ASODN) have been reported to selectively inhibit ph+ leukemic progenitors by induced apoptosis. Here we reported four CML patients with ABMT after in vitro purging with bcr/abl ASODN. 4 cases with CML were 2 in chronic phase, 1 in accelerated phase and 1 in blast crisis. Before bone marrow harvest, the patients had received 2 or 3 courses intensive chemotherapy for "vivo purging"(Har 4mg/dayX 7+Ara-C 0.5g/dayX 7 or Har 4mg/dayX 7+Ara-C Ig/dayX 3+ VP16 100mg/dayX5), and obtained a reduced content of ph+ cells(ph+ 24-47%). Bone marrow mononuclear cells were concentrated by CS3000plus(Baxter). A total mononuclear cells of 1.1-1.38X lO'/kg containing GM-CFC 6.9-I0.9X 10/kg were collected. The cells were incubated with 18mer phosphorothioate bcr/abl ASODN(40~60ug/ml) for 48~60h, and 81-92% mononuclear cells and 31-52% GM-CFC were recovered. 2 cases with ph+ 24% and 27% before purging had bcr/abl mRNA(-) in residual CFU-GM by RT-PCR. The patients were conditioned with TBI/Cy. The hematological reconstitution was slower than other ABMT at same time. Granlocytes>0.5�� 10 9/L and platelets>50 X lO'/L were at day +18-+31 and +24-+6S. Besides 1 cases was died of infection at +74 day, 2 cases had a proportion of ph- hematological reconstitution (+3 month ph+<25%, +9 month ph-K30% and +12 month ph+<45%). 1 case in blast crisis with masked ph is now in complete hematological remission 10 months post-ABMT without any treatment. All 3 cases continually had bcr/abl mRNA(+) detected by RT-PCR. These results indicate that bcr/abl ASODN be useful for autograft purging and may have more effective in low-dose leukemic cells patients after "vivo purging". It need notice that hematological reconstitution was prevented because low count residual normal GM-CFC after purging.