Hybridization protection assay: a rapid, sensitive, and specific method for
detection of Philadelphia chromosome-positive leukemias
K Dhingra, M Talpaz, MG Riggs, PS Eastman, T Zipf, S Ku and R Kurzrock
Department of Clinical Immunology and Biological Therapy, University of
Texas M.D. Anderson Cancer Center, Houston 77030.
The Philadelphia (Ph1) chromosome is present in greater than 90% of
patients with chronic myelogenous leukemia (CML) and in 2% to 20% of those
with acute leukemias, for which it is an important prognostic marker too.
The chimeric BCR-ABL mRNAs resulting from the translocation encode either a
210-Kd or a 190-Kd protein. The techniques used to detect Ph1 chromosome
include karyotyping, Southern analysis to demonstrate bcr rearrangement,
and polymerase chain reaction to amplify the BCR-ABL transcripts. However,
the routine performance of these methods by clinical laboratories is
cumbersome, time consuming, and exposes laboratory personnel to
radioisotopes. We describe here the clinical application of a new method,
the hybridization protection assay (HPA), which uses chemiluminescent
acridinium-ester-labeled probes in conjunction with PCR for detection of
the amplified BCR-ABL sequences. The method is sensitive, specific, and can
reliably distinguish between the transcripts for P190BCR-ABL and
P210BCR-ABL. In contrast to the 2 days or longer required for conventional
hybridization, HPA analysis can be completed in less than 30 minutes. We
have successfully used this method to analyze 60 leukemia samples (34 from
Ph1-negative acute leukemias; 6 from Ph1-positive acute leukemias; and 20
from CML) with complete correlation (of BCR-ABL positivity or negativity)
with the results of karyotype or Southern Blot analysis of genomic DNA for
bcr rearrangement. Therefore, the HPA, in conjunction with PCR, appears to
provide a rapid and reliable test for the diagnosis of Ph1-positivity.
Volume 77,
Issue 2,
pp. 238-242,
01/15/1991
Copyright © 1991 by The American Society of Hematology
