IL18 Knockout DLD-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human DLD-1 colorectal adenocarcinoma cell line. This product provides a loss-of-function model for the IL18 gene, achieved through CRISPR/Cas9-mediated gene disruption, yielding a heterogeneous pool of knockout cells suitable for pooled functional studies. The polyclonal format preserves population-level variability, enabling robust assessment of IL18-dependent phenotypes in colorectal cancer biology. This model system allows researchers to interrogate the functional consequences of IL18 loss without the confounding effects of clonal selection, making it ideal for studying heterogeneous tumor cell populations.
The DLD-1 cell line is an extensively characterized model of colorectal adenocarcinoma, originally isolated from a 47-year-old male with Dukes’ type C disease. These epithelial cells exhibit high microsatellite instability (MSI-H) and harbor key oncogenic mutations in APC, KRAS, TP53, and PIK3CA, recapitulating the genetic landscape of sporadic colorectal cancers with mismatch repair deficiency. DLD-1 cells are widely used for investigating tumor cell-intrinsic signaling, drug response, and tumor-immune interactions in the colorectal cancer microenvironment. The well-defined mutational profile provides a genetically tractable platform for studying oncogenic signaling crosstalk.
IL18 encodes a potent proinflammatory cytokine belonging to the IL-1 superfamily. Synthesized as an inactive precursor, IL-18 is proteolytically activated by caspase-1 upon assembly of the NLRP3 inflammasome, which responds to Toll-like receptor (TLR) ligands and danger signals. Mature IL-18 binds to its heterodimeric receptor complex comprising IL18R1 and IL18RAP, recruiting MyD88, IRAK4, and TRAF6 to propagate downstream signals. This cascade activates NF-kB and MAP kinases, including JNK and p38, driving transcription of IFN-gamma, TNF-alpha, and IL-6 that orchestrate Th1 immune responses. Negative regulation is provided by the decoy receptor IL18BP.
In DLD-1 cells, abrogation of IL-18 expression provides a powerful system to dissect its dichotomous functions in colorectal cancer. While IL-18 can enhance anti-tumor immunity by promoting IFN-gamma production and NK cell cytotoxicity, it may also foster a tumor-permissive inflammatory milieu characterized by sustained NF-kB and MAPK pathway activity. The polyclonal IL18 knockout in DLD-1, with its MSI-H background and activating KRAS and PIK3CA mutations, enables investigation of cytokine crosstalk that directly interfaces with oncogenic signaling. This model is particularly pertinent for studying how inflammasome-derived IL-18 influences tumor-intrinsic processes such as proliferation, migration, and drug sensitivity, as well as for evaluating how loss of IL-18 alters the secretome that shapes the immune microenvironment.
These IL18 knockout cells are suited for advanced applications including Western blotting, RT-qPCR, and ELISA to quantify cytokine and signaling proteins. Flow cytometry and NF-kB reporter assays can evaluate immune activation and transcription factor dynamics. Co-immunoprecipitation experiments explore inflammasome component interactions, while migration/invasion and drug sensitivity assays reveal tumor cell contributions. The cells also support preclinical evaluation of IL-18-neutralizing agents or pathway inhibitors in colorectal cancer and inflammatory bowel disease-associated carcinogenesis. For further information or technical support, please contact Ascent Research.
