Autologous Bone Marrow Transplantation - Blog Science Connections

Transplantation for Neuroblastoma Using
Immunomagnetically Purged Autologous
Bone Marrow
Adrian P. Gee, John Graham-Pole, Carlos Lee, Karen Bruce,
Terry Pick, Walter Harvey, Diana Worthington-White,
Marilyn Hintz, William Janssen, and Samuel Gross
Although using autologous bone marrow avoids limitations associated with
allogeneic transplantation, namely, nonavailability of donors and reactions
between the graft and host, its use is restricted in neuroblastoma by the high
incidence of marrow infiltration by malignant neuroblasts. If this infiltration
could be overcome, then all these patients could potentially benefit from
autologous bone marrow infusions for hematologic support.
In vitro immunomagnetic purging ( 1,2) appears to be one of the safest and
most effective methods of selectively eliminating malignant cells from bone
marrow. In this procedure, target neuroblasts are identified using monoclonal
antibodies. They are linked to magnetic microspheres, and then the beadcoated
cells are removed by passing the bone marrow through a magnetic field.
Unlike complement-mediated purging, this method does not depend on using
antibodies of a particular isotype or subclass, is unaffected by anticomplementary
factors associated with normal bone marrow cells (3), and can be used
to eliminate cells expressing low levels of target antigen (4). Here we report
preliminary results of a pilot study using immunomagnetically purged bone
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