Autologous Bone Marrow Transplantation - Blog Science Connections

Ex Vivo Marrow Purging 95
Table 1. Effect of Protocol on CFU-GM Recovery and Reh6 Cell Line Growth
Protocol
CFU-GM Recovery (%)
Day 7 Day 21
(n = 4) (n = 4)
Reh6 Cell Target
Log Cell Kill
(n = 4)
Complement 77.4 ± 4.8 91.5 ± 12 0.16 ± 0.02
CD10 + CD19 + C1C2 79.8 ±11.9 100 3.4 ± 0.1
Mafosfamide 12.8 ± 9.1 51 ± 35 2.9 ± 0.5
(30 AJg/ml)
CD10 + CD19 + C1C2 11 ± 8 45.5 ± 38 4.7 ± 0.2
+ mafosfamide
Abbreviation: C1C2, two cycles of complement.
REPORT OF A CASE
We examined the feasibility of ABMT using marrow treated with CD 10 and
CD 19 MAbs with two cycles of complement and mafosfamide before
cryopreservation. The patient was a child with non-T, non-B ALL in fourth
remission.
The 1 -year-old boy was first admitted to our hospital in October 1984. An
ALL diagnosis was established—he was considered pre-B ALL, his test results
were positive for the common acute lymphoblastic leukemia antigen (CALLA),
and he was classed as L-, according to the French-American-British classification
system. The disease was induced into remission in November 1984 with
the Berlin-Frankfurt-Munich protocol (10). In January 1985 the first marrow
relapse occurred on therapy. When three courses of chemotherapy failed to
reach a durable remission, the patient was put into fourth remission by one
course of high-dose cytarabine and amsacrine. Given that no donor was
available for allogeneic bone marrow transplantation, autologous marrow was
harvested during the fourth remission. We harvested 8 x 10 8
nucleated cells/kg
and 1 x 10 5
CFCI-GM/kg. To eliminate leukemic cells, we incubated the cells in
CD 10 and CD 19 and added baby rabbit complement for two cycles and 30
Mg/ml mafosfamide for 30 minutes at 37° C (Fig 1). The CFU-GM recovery was
0.1 %; continuous liquid culture (21 days) produced a CFU-GM recovery of 13%.
Before treatment, cytofluorometry revealed 17% CALLA-positive cells in the
inoculum, but after the complement-mediated cytolysis, only 2 CALLA-positive
cells (ethidium bromide negative) were detected in 500 marrow cells.
The ablative regimen consisted of a fractionated total body irradiation
during 3 days at 2 Gy/fraction up to a total of 12 Gy, followed by high-dose
cytarabine (3 g/m 2
every 12 hours for eight doses) and high-dose melphalan
(140 mg/m 2 ). This protocol was well tolerated by our patient. The hematopoiesis
recovery occurred slowly (1 x 10 9 leukocytes/1 on day 24, 0.5 x 10 9
granulocytes/1 on day 26, and 50 x 10 9 platelets/I on day 37) (Fig 2).
The patient has not received additional chemotherapy following the ABMT
procedure. He is alive and well in complete remission 8 months after ABMT.