CMN Weekly (7 March 2025) - Your Weekly CRISPR Medicine News

Top picks

• American researchers have shown that incorporating nitro-oleic acid (NOA) into plasmid DNA-loaded lipid nanoparticles (pDNA-LNPs) mitigates acute inflammation in mice by inhibiting the cGAS–STING pathway. This modification enabled prolonged transgene expression, 11.5 times greater than mRNA-LNPs at day 32. Further optimisation increased in vitro expression 50-fold. NOA-pDNA-LNPs offer a safer, more efficient platform for long-term, promoter-controlled gene expression in genetic medicine.
• Prime editing of the obesogenic FTO^rs9939609-A allele in human embryonic stem cells has revealed its role in accelerating skeletal muscle development and insulin resistance. The allele increased expression of the fat mass and obesity-associated (FTO) gene, enhancing H19/IGF2 signalling via m6A demethylation. While promoting early growth, this overstimulation led to insulin resistance upon ageing or high-fat diet exposure. These findings clarify FTO's paradoxical link to both leanness and obesity.

Research

• CRISPR-Cas9 knockout of diacylglycerol kinase (DGK) α and ζ has been shown to enhance TAG-72 CAR-T cell efficacy against ovarian cancer. The modification improved persistence and anti-tumor activity without affecting viability. DGKα/ζ KO CAR-T cells eradicated tumours in vivo for up to 100 days, whereas controls showed relapse by day 40. This strategy strengthens CAR-T responses in solid tumours, overcoming immune suppression and improving long-term tumour control.
• An American study has explored how enlarging the recognition (REC) domain of CRISPR-Cas9 can improve adenine base editing accuracy. The researchers at Tufts University engineered a "giant" SpCas9 (GS-Cas9) by expanding the REC domain, demonstrating reduced off-target effects and improved precision of the adenine base editor ABE8e.
• Researchers found that Cas9 interacts with ribosomes in mammalian cells, sequestering it in the cytoplasm. This interaction is RNA-mediated and reduces Cas9 nuclear entry. Increasing the number of nuclear localisation signals (NLSs) or cytoplasmic guide RNA levels can help overcome ribosomal binding, improving CRISPR-Cas9 nuclear localisation and genome-editing efficiency.

Industry

• Verve Therapeutics has announced full-year 2024 financial results with a net loss of $199 million and $524 million in cash.
• Intellia Therapeutics has announced full-year 2024 financial results with a net loss of $129 million and $862 million in cash.
• Iovance Biotherapeutics has announced full-year 2024 financial results with a net loss of $372 million and approximately $422 million in cash.
• Prime Medicine has announced full-year 2024 financial results with a net loss of $196 million and $205 million in cash.
• Fate Therapeutics has announced full-year 2024 financial results with a net loss of $186 million and $307 million in cash.
• Editas Medicine has announced full-year 2024 financial results with a net loss of $237 million and $270 million in cash.
• Beam Therapeutics has announced full-year 2024 financial results with a net loss of $377 million and $851 million in cash.

Clinical

• Korro Bio has begun dosing in its REWRITE study evaluating KRRO-110, an RNA-editing therapy for Alpha-1 Antitrypsin Deficiency (AATD). KRRO-110 uses endogenous ADAR enzymes to correct a SERPINA1 mutation, restoring functional AAT protein. The trial will assess safety, pharmacokinetics, and pharmacodynamics in up to 64 participants. Interim data from single-dose cohorts is expected in late 2025, with study completion anticipated in 2026.

Delivery

• Peptide-enabled ribonucleoprotein delivery for CRISPR engineering (PERC) is a new method that enables efficient CRISPR ribonucleoprotein delivery into primary human cells using a single amphiphilic peptide. It supports gene knockout, transgene knock-in, and base editing with high efficiency (>90%) in T cells and HSPCs. Unlike electroporation, PERC is hardware-free, minimally disruptive, and allows multiple treatments.

Screening

• CRISPR-Cas knockout screens often miss context-essential genes due to model variability. PRODE, a computational framework integrating gene effects with protein interactions, refines essentiality assessments. It improves recovery of missed essential genes in shRNA screens and prioritises context-essential hits in CRISPR-KO data. In Her2+ breast cancer, PRODE identifies oxidative phosphorylation genes as vulnerabilities, suggesting new therapeutic targets.

Detection

• A CRISPR-based RT-PCR assay has improved the diagnosis of the life-threatening fungal disease Pneumocystis jirovecii pneumonia (PCP) by enhancing sensitivity and specificity in non-invasive samples. In infants, oropharyngeal swab detection outperformed RT-qPCR (96.3% vs. 66.7% sensitivity). In adults, serum CRISPR assays were far superior (93.3% vs. 26.7% sensitivity).
• Researchers in China have presented an updated version of the SCas12a assay, which combines Cas12a with a split crRNA comprising a 20-nt scaffold RNA and a variable 20-nt spacer RNA. The new SCas12aV2 system enhances CRISPR-Cas12a-based RNA detection by reducing steric hindrance, enabling precise, amplification-free sensing of structured RNAs. Optimised scaffold RNA and hybrid activators improve sensitivity, achieving a 246 aM detection limit and accurately identifying SNPs, viable bacteria, and SARS-CoV-2 in clinical samples.
• Researchers in China have developed a modular microfluidic sensor integrating CRISPR-Cas13a and electrochemiluminescence (ECL) for rapid RNA-based pathogen detection. The system streamlines nucleic acid extraction and distribution, achieving detection in 30 minutes with a 0.372 fM sensitivity for E. coli 16S rRNA. It enables multiplexed detection, including real-time monitoring of bacterial growth in mixed cultures.
• A multiplex-gRNA-assisted CRISPR-Cas12a biosensor (MgCPA) enables amplification-free, quantitative detection of malathion using a glucometer. The system activates Cas12a's trans-cleavage upon malathion binding, releasing glucose signals for detection. With a sensitivity of 300 fM, it offers high selectivity, reproducibility, and stability, demonstrating practical use in food safety monitoring across various produce samples.

Reviews

• CRISPR integrated biosensors: A new paradigm for cancer detection. This review explores CRISPR-based biosensors for cancer diagnostics, highlighting their precision, sensitivity, and cost-effectiveness over conventional methods, with a focus on detecting lung, liver, colorectal, prostate, and cervical cancers.
• Application and development of CRISPR-Cas12a methods for the molecular diagnosis of cancer: A review. This review systematically explores the development, key technologies, and applications of CRISPR-Cas12a-based molecular diagnostics in cancer detection, highlighting its potential for clinical implementation.