Abnova’s mutaFISH™ Probes Energize the Fluorescent In Situ Hybridization Global Market and Propel New Precision Medicine Applications

Neihu, Taiwan (October 29, 2019)

Abnova announced today the launching of an expanding collection of mutaFISH™ probe bioreagents (www.abnova.com/technologies/mutaFISH) to energize the fluorescent in situ hybridization (FISH) global market and propel new precision medicine applications. Current FISH probes developed in the 1980s (1) were first recognized for their inherent ability to identify DNA and RNA at a the cell and subcellular levels. As an visualization tool, they quickly gained enormous popularity in prenatal and cancer community to analyze gross chromosomal and genetic changes. By 2018, FISH probes have achieved an impressive worldwide market of $621 million USD (2). However, in the face of precision medicine and increasing competitions from digital polymerase chain reaction (dPCR) and next-generation sequencing (NGS), traditional FISH probes fall short of their ability to recognize single nucleotide mutations which are the main driving force behind today’s growing companion diagnostics and personalized therapies. Abnova mutaFISH™ probes based on padlock probe and rolling circle amplification technologies have been bioengineered to fulfill this unmet need and are poised to drive new applications and markets in tissue, cell, exosome, plasma and urine-based DNA and RNA detection, visualization, and quantification.

Traditional FISH probes are made of long nucleotides labeled with fluorescent dyes. This elegant design makes them extremely powerful for studying gross cytogenetic changes such as prenatal chromosomal aneuploidies (trisomies and monosomies), cancer related gene amplification (HER2, PD-L1), translocation (EMLA-ALK), and deletion (p53). Unfortunately, as design dictates function, FISH probes are too large to recognize the subtle single nucleotide changes such as point mutation, insertion, and deletion in DNAs and RNAs. On the other hand, mutaFISH™ probe is built with a shorter, circularized padlock probe setup to recognize single nucleotide difference based on a T4 DNA ligase which anneals only complementary nucleotides. After ligation, an isothermal phi29 DNA polymerase amplifies the circular templates followed by the attachment of fluorescent oligonucleotide probes for detection. As a result, the sensitivity of mutaFISH™ detection is higher than that of dPCR and NGS (3). mutaFISH™ probes can also detect small-size nucleotides such as miRNA and other non-coding RNAs. Moreover, mutaFISH™ can fulfill all the previous functions of traditional FISH probes except for analyzing gain or loss of whole chromosome.

In the wake of precision medicine, single nucleotide mutations in tissues but also in circulating cells and exosomes are become increasingly important. For example, after enrichment and isolation of circulating tumor cells (CTCs), antibody staining of protein biomarkers is used to substantiate the identity of CTCs. However, low number of CTCs is often prohibitory for downstream genetic analysis, even after whole genome amplification (WGA). In contrast, mutaFISH™ is well-suited to amplify and validate the genetic signature of CTCs in situ. Like CTCs, circulating exosomes are secreted, extracellular particles surrounded by a lipid bilayer containing proteins, mRNAs and miRNAs but without a nucleus. mutaFISH™ can be efficiently applied to circulating exosomes to analyze the genetic markup of cell-cell communications, cancer cell transformation and metastasis, and immune cell regulation. More excitingly, mutaFISH™ can be combined with quantitative polymerase chain reaction (qPCR) to detect plasma and urine’s free DNAs and RNAs for early cancer screening, diagnosis, and monitoring. While dPCR and NGS could meet these goals, they are more cumbersome, higher cost, and less sensitive. Abnova’s mutaFISH™ can better simplify operation, lower costs, and implement point-of-care precision medicine of tomorrow.

1. The origin of in situ hybridization - A personal history, Methods. 2016 Apr 1;98:4-9.

2. In Situ Hybridization Market by Type and Size - Industry Report 2018-2023

3. Sensitive and inexpensive digital DNA analysis by microfluidic enrichment of rolling circle amplified single-molecules, Nucleic Acids Research, Volume 45, Issue 8, 5 May 2017, Page e59