The IDO1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HAP1 human haploid fibroblast-like cell line. This product provides a loss-of-function model for the immunoregulatory enzyme IDO1 (indoleamine 2,3-dioxygenase 1), generated by CRISPR/Cas9-mediated gene disruption, and is supplied as a mixed population of edited cells to support diverse functional assays in immunology and cancer research.
HAP1 cells are a near-haploid human cell line originally derived from the KBM-7 chronic myeloid leukemia (CML) cell line, which harbors the BCR-ABL1 fusion gene. Their haploid karyotype simplifies genetic analysis by eliminating the complexity of heterozygous mutations, making them a robust model for CRISPR-based functional screens, gene essentiality studies, and pathway dissection. The fibroblast-like morphology and stable growth characteristics further enhance their utility in high-throughput and reproducible experimental setups.
IDO1 is a heme-containing enzyme that catalyzes the rate-limiting step of tryptophan catabolism along the kynurenine pathway, converting L-tryptophan into kynurenine and downstream metabolites such as kynurenic acid and quinolinic acid. Its expression is tightly regulated by inflammatory stimuli, including IFNG, TNF, IL-1, and TLR ligands, acting through STAT1 and IRF1. Elevated kynurenine activates the aryl hydrocarbon receptor (AhR), promoting T-cell anergy, regulatory T-cell differentiation, and immunosuppression via tryptophan depletion and mTOR inhibition. IDO1 also interacts with IDO2 and requires heme as a cofactor.
IDO1 knockout in HAP1 cells abolishes tryptophan catabolism and AhR-mediated immunosuppressive signaling, as the haploid genome permits complete gene disruption without diploid compensation. Combined with the BCR-ABL1 background, this model allows dissection of immune evasion pathways in a leukemia-relevant context, and it supports studies in cancer, autoimmunity, and infectious disease.
These polyclonal cells are ideal for immune checkpoint research, tumor immunology, kynurenine pathway metabolic analysis, and screening of IDO1 inhibitors. Typical assays include western blotting, RT-qPCR, kynurenine ELISA, tryptophan HPLC, AhR luciferase reporter, and enzymatic activity measurements. The model enables validation of CRISPR editing, AhR network dissection, and co-culture experiments with immune cells. For further technical information, contact Ascent Research.
