Use of the polymerase chain reaction to monitor the effectiveness of ex
vivo tumor cell purging
RS Negrin, HP Kiem, IG Schmidt-Wolf, KG Blume and ML Cleary
Division of Hematology, Stanford University Medical Center, CA 94305.
The polymerase chain reaction (PCR) was used to detect residual malignant
disease before and after ex vivo purging with monoclonal antibodies and
complement or immunomagnetic treatment of BM samples contaminated with
known numbers of t(14;18)-carrying tumor cells. Sensitivity of the PCR was
demonstrated by detecting a specific t(14;18) amplification product in DNA
extracted from a preparation consisting of one tumor cell among 10(5)
normal cells. When BM contaminated with 1% to 5% t(14;18)-carrying cells
from the B-cell lymphoma line SU-DHL-4 was subjected to two rounds of
anti-B-cell pool of antibodies and complement (Ab-C) treatment a 3- to
4-log reduction of the pretreatment PCR signal was observed. A similar
log-cell kill was detected using an independent clonogenic assay confirming
the utility of the PCR approach. BM contaminated with a second B-cell
lymphoma cell line, OCI-Ly8, was more resistant because a third cycle of
Ab-C treatment was required to obtain a similar reduction in the PCR
signal. A similar 4 logs of tumor cell removal was obtained using anti-
B-cell antibodies conjugated to magnetic beads. These studies demonstrate
that the t(14;18) PCR can be used to detect levels of tumor cells as low as
0.001%. This approach can be used to determine the effectiveness of BM
purging in patients undergoing autologous BM transplantation as well as to
assess the biologic role of minimal marrow disease.
Volume 77,
Issue 3,
pp. 654-660,
02/01/1991
Copyright © 1991 by The American Society of Hematology
