CRISPR Gene Knockout Through Direct Nuclear Delivery

CRISPR knockout is a genome editing technique that permanently disables gene expression. It uses guide RNA to direct Cas9 nuclease to specific DNA sequences adjacent to PAM motifs, creating double-strand breaks. These breaks are repaired through error-prone NHEJ, generating insertions or deletions that cause frameshift mutations, introducing premature stop codons and triggering nonsense-mediated decay of mRNA.

Key challenges include delivering CRISPR-Cas to the nucleus across membrane barriers, limited control over nuclear RNP dose leading to variable editing, risk of random vector integration, and delivery-associated cytotoxicity especially in sensitive cells like iPSCs. These issues result in heterogeneous editing outcomes and reduced cell viability.

FluidFM uses a hollow cantilever with nanoscale aperture to directly inject femtoliter volumes of Cas RNP into the nucleus, bypassing membrane barriers and minimizing cytosolic degradation. This enables controlled stoichiometry for dual-gRNA editing, supports multiplex knockout, and maintains higher cell viability compared to bulk transfection methods.

The CellEDIT workflow includes: initial feasibility discussion and reagent design, cell line QC and optimization, low-density cell plating (300 cells), direct nuclear injection of CRISPR RNP into all cells, singulation and monoclonal expansion, PCR and Sanger sequencing screening, and final quality control for viability and contamination.

CellEDIT can create knockouts through frameshift mutations, deletion of specific genetic regions, editing of regulatory regions, multiplex editing targeting multiple loci, large deletions using double gRNA approach, and small knock-ins including point mutations or insertions under 120bp in dedicated cell lines.

Vector-free delivery through direct intra-nuclear injection eliminates risks of random genomic integration that can confound phenotypes and introduce insertional mutagenesis. It provides precise control over RNP concentration and stoichiometry in target cells, reduces off-target effects, and is particularly effective for delicate and hard-to-transfect cell lines.

Knockout cell lines are used for understanding disease mechanisms by creating models that mimic disease states, determining gene function through loss-of-function studies, identifying therapeutic targets, validating drug specificity and efficacy, assessing treatment toxicity, and supporting pathway analysis in drug discovery research.

CellEDIT provides knockout monoclonal cell lines for selected cell lines. This timeline includes the complete workflow from initial consultation through cell line engineering, validation, and quality control, delivering 2 genome-engineered and 2 control cell lines.

CRISPR knockout is a gene editing technology that uses CRISPR-Cas9 to permanently disable specific genes in cells. This allows researchers to study gene function, understand disease mechanisms, identify therapeutic targets, and validate drug candidates by observing what happens when a particular gene is removed.

Vector-free delivery minimizes off-target effects by delivering CRISPR-Cas9 RNP complexes directly into the nucleus without viral vectors or plasmid DNA. This approach avoids random genomic integration and reduces CRISPR component exposure time in the cell, limiting opportunities for unintended edits at similar genomic sequences.

CellEDIT knockout services support multiple cell lines including U2OS, CHO, HeLa, MCF-7, C2C12, HEK293, MDA MB 231, A549, and KPC cells. The service is particularly effective for hard-to-transfect cells that resist traditional transfection methods and also accepts user-supplied cells for custom engineering projects.

CellEDIT generates custom monoclonal knockout cell lines in approximately 10 weeks from project initiation. This accelerated timeline is enabled by efficient direct intra-nuclear delivery using FluidFM technology, which bypasses many challenges associated with traditional transfection approaches.

CellEDIT knockout services provide comprehensive deliverables including edited monoclonal cell clones, gRNA design reports documenting the targeting strategy, sequencing results confirming genetic modifications, and genotype verification. Customers retain full intellectual property rights to the edited cell lines.

Knockout technology is critical for drug discovery because it enables target identification and validation by revealing which genes are essential for disease processes. By creating cells with specific genes disabled, researchers can validate whether a gene is a viable therapeutic target, assess potential drug efficacy, and understand mechanism of action.