The IDO1 Knockout A-549 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from Homo sapiens A-549 lung adenocarcinoma epithelial cells. This product disrupts the IDO1 gene through targeted genome editing, generating a heterogeneous pool of cells with loss-of-function mutations. The polyclonal format avoids clonal bias and provides a robust model for studying IDO1-dependent pathways.
The parental A-549 cell line is a well-established model of alveolar type II pulmonary epithelium, widely used in lung cancer research and drug metabolism studies. These cells exhibit low basal IDO1 expression but can be potently induced by inflammatory stimuli such as interferon-gamma. Their epithelial origin and characterized signaling networks make them an ideal host for investigating tumor-intrinsic immune evasion mechanisms.
IDO1 functions as the rate-limiting enzyme of the kynurenine pathway, catalyzing the conversion of tryptophan to N-formylkynurenine. This reaction leads to local tryptophan depletion and production of immunosuppressive kynurenine metabolites. IDO1 is transcriptionally upregulated by IFN-??, IFN-??, IFN-??, TNF-??, TLR ligands, and IL-1. Downstream, its activity promotes signaling through the aryl hydrocarbon receptor (AhR), activates GCN2 kinase stress response, and suppresses mTOR pathway activity. IDO1 also interacts with SHP-1, SHP-2, and TRAF6, and participates in non-catalytic signaling via Src family kinases, collectively fostering T-cell anergy and regulatory T-cell expansion.
In A-549 lung adenocarcinoma cells, IDO1 knockout eliminates a critical immunosuppressive mechanism inherent to the tumor microenvironment. Ablation of tryptophan catabolism prevents the accumulation of kynurenines, thereby alleviating T?cell suppression and enabling anti?tumor immunity. This model is particularly valuable for dissecting cancer cell-intrinsic contributions to immune checkpoint resistance and for evaluating combinatorial strategies with checkpoint inhibitors. Co?culture with primary T cells allows direct assessment of functional immune recovery.
Research applications include tumor immunology, immune checkpoint research, and autoimmune disease modeling. Key assays for knockout validation encompass RT?qPCR and western blotting for IDO1 expression, kynurenine quantitation, T?cell proliferation and flow cytometry analyses, and tumor xenograft studies. The polyclonal composition is suitable for pooled screening workflows. For further details, please contact Ascent Research.
