Sound-Guided CRISPR: Ultrasound Unlocks Precision Gene Editing

In the pursuit of a precise way to control CRISPR-mediated gene editing, scientists in the United States and China have engineered a set of inducible CRISPR-based tools that are controllable by focused ultrasound (FUS), which can penetrate tissue tens of centimetres deep and directly induce localised hyperthermia.

FUS has previously been used for tissue ablation in patients at relatively high temperatures (> 60 °C) and for controlling transgene expression in vivo at mildly elevated temperatures, (42−43 °C) using heat-sensitive promoters.

Based on their previous work showing that FUS-inducible CAR-T cells can be activated by FUS for cancer therapy with reduced off-tumour toxicities, the team hypothesised that a similar approach could be used to precisely control CRISPR-based genome editing without the need for co-factors for genome editing and regulations at specific tissues and organs.

In an article published yesterday in Nature Communications, they show that the FUS-inducible system is indeed suitable for CRISPR activation (CRISPRa) of gene expression and CRISPR epigenetic editing (CRISPRee). They demonstrate inducible upregulation, downregulation, and knockout of exogenous and/or endogenous genes in multiple cell types in vitro and in vivo in mice (1).

They succeeded in applying FUS-CRISPR to generate double-stranded DNA breaks at telomere sites in tumour cells, which primed solid tumours for efficient killing by cytotoxic CAR-T cells in vitro and in vivo. Furthermore, systemic delivery of FUS-CRISPR via adeno-associated virus led to reprogramming of tumour cells and primed a sub-population of synNotch CAR-T cells via the “training centre” strategy to attack the entire population of cancer cells (2, 3).

The work was led by Professor Peter Yingxiao Wang at the Alfred E. Mann Department of Biomedical Engineering at the University of Southern California (USC). In an article published on the USC Viterbi School of Engineering website, Peter Yingxiao Wang said: »CRISPR is revolutionary. You can do genome or epigenome editing right in the cell nucleus — so that essentially, you can treat genetically-related diseases. But we are pushing it one step further to make it controllable. Instead of continuously editing the genome, we can now control it to be activated at a specific location and at a specific time using a non-invasive remote-controlled ultrasound wave. That’s the breakthrough.«

References

1. Wu Y, Huang Z, Liu Y, et al. Ultrasound Control of Genomic Regulatory Toolboxes for Cancer Immunotherapy. Nat Commun. 2024 Dec 1;15(1):10444.
2. Morsut L, Roybal KT, Xiong X, et al. Engineering Customized Cell Sensing and Response Behaviors Using Synthetic Notch Receptors. Cell. 2016 Feb 11;164(4):780-91.
3. Chi Woo Yoon, Chunyang Song, Dung Ngo Minh Nguyen, et al. Tumor Priming by Ultrasound Mechanogenetics for with SynNotch CAR T Therapy. bioRxiv 2024.10.01.615989.