An ultrasensitive fluorescence sensing strategy for detection and in situ imaging of chronic myeloid leukemia-related BCR-ABL1 mRNA

In this study, a fluorescent sensing strategy has been developed for rapid and ultrasensitive detection of BCR-ABL1 mRNA in chronic myeloid leukemia (CML) based on DNAzyme Cleavage-induced Rolling circle amplification (DCR for short). In the presence of BCR-ABL1 mRNA, DNAzyme was activated to split the target sequence into two fragments, producing the 3′ terminus on the forward cleavage fragments. After T4 polynucleotide kinase (PNK) modification reaction, the forward cleavage fragments were extended by rolling circle amplification (RCA). Plenty of long single DNA strands were produced and partially hybridized with the fluorescence-quenching decorator probes, thus inducing the separation of fluorophore and quencher decorator probes and recovery of fluorescence. Highly sensitive detection of BCR-ABL1 was achieved with a limit of detection at 9.4 fM. In addition, the DCR strategy was adopted to successfully in situ image the BCR-ABL1 mRNA in the cytoplasm of human leukemia bone marrow cells. Moreover, results of the BCR-ABL1 mRNA expression in clinical samples achieved by DCR sensing were well consistent with that of reverse transcription PCR (RT-PCR) and fluorescence in situ hybridization (FISH) analysis. Therefore, this developed DCR sensing strategy might provide a potential alternative tool for precise diagnosis of CML.

Source: Sensors and Actuators B: Chemical - July 19, 2018 Category: Chemistry Source Type: research