The IDO1 Knockout KYSE-30 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human esophageal squamous cell carcinoma line KYSE-30, engineered to harbor a functional disruption of the indoleamine 2,3-dioxygenase 1 (IDO1) gene. This polyclonal pool contains a heterogeneous mixture of edited cells, each carrying distinct gene-disrupting events, providing a robust loss-of-function model without selecting for a single clonal genotype. The CRISPR/Cas9-mediated gene disruption eliminates IDO1 enzymatic activity, enabling researchers to dissect its roles in tryptophan metabolism and immune regulation directly in the esophageal carcinoma context.
The parental KYSE-30 cell line was established from a poorly differentiated invasive esophageal squamous cell carcinoma and serves as a widely used in vitro model for esophageal cancer biology. These adherent epithelial cells retain aggressive growth properties and responsiveness to inflammatory cytokines, making them particularly relevant for investigating tumor?Cimmune interactions, metabolic adaptations, and therapeutic sensitivities in a tumor type with limited treatment options.
IDO1 is the rate-limiting enzyme in the kynurenine pathway of tryptophan degradation, catalyzing the oxidative cleavage of tryptophan to N-formylkynurenine. Its expression is strongly induced by inflammatory stimuli such as interferon-gamma (IFN-??), tumor necrosis factor-alpha (TNF-??), interleukin-6 (IL-6), and Toll-like receptor (TLR) ligands, often via JAK/STAT signaling. This leads to local tryptophan depletion and generation of kynurenine and downstream metabolites, including kynurenic acid and quinolinic acid. Kynurenine acts as an endogenous ligand for the aryl hydrocarbon receptor (AhR), triggering a signaling cascade that promotes differentiation of regulatory T cells (Tregs), suppresses mTORC1 activity, and activates the GCN2 kinase pathway, collectively dampening effector T cell responses and fostering immune tolerance. IDO1 activity requires heme as a cofactor and is negatively regulated by suppressor of cytokine signaling 3 (SOCS3). Although the related enzyme TDO2 also participates in tryptophan catabolism, IDO1 dominates extrahepatic immune-regulatory functions.
In the KYSE-30 esophageal cancer context, IDO1-mediated kynurenine-AhR signaling may contribute to an immunosuppressive tumor microenvironment, aiding immune escape. Disruption of IDO1 in this polyclonal knockout system enables direct interrogation of how loss of IDO1 alters tryptophan metabolism, kynurenine secretion, and the ability of cancer cells to influence T cell function. This model is valuable for dissecting cancer cell?Cimmune crosstalk and evaluating the impact of IDO1 ablation on tumor cell proliferation, survival, and sensitivity to chemotherapeutic or targeted agents.
Researchers can use this polyclonal pool in cancer immunotherapy research, tumor microenvironment immune profiling, T cell proliferation assays, checkpoint inhibitor combination studies, and AhR signaling modulation. Representative assays include Western blotting and RT-qPCR for IDO1 expression analysis, kynurenine quantification by ELISA or HPLC, co-culture systems with T cells, flow cytometry for immune markers, AhR reporter assays, and metabolomics profiling of tryptophan catabolism. Drug sensitivity studies with IDO1 inhibitors such as epacadostat are also possible. For technical specifications, ordering details, or further assistance, please contact Ascent Research.
