The IDO1 Knockout 143B Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population engineered to disrupt the IDO1 gene in the human 143B osteosarcoma cell line. This product offers a mixed population of cells with targeted gene disruption, providing a robust loss-of-function model to explore IDO1-dependent tryptophan catabolism and immune suppression. The polyclonal nature preserves the heterogeneity of the parental line, enabling reproducible experimental conditions without the confounding effects of clonal drift.
The parental 143B cell line is a human osteosarcoma model derived from a 10-year-old female, carrying a TP53 mutation that abrogates p53 function. Widely utilized in cancer biology and mitochondrial research, 143B cells exhibit rapid growth and are permissive to genetic manipulation. Their p53-deficient status makes them particularly relevant for studying tumorigenic processes, including metabolic reprogramming and resistance to apoptosis, providing a pertinent background for IDO1 knockout studies in a malignant context.
IDO1 catalyzes the initial and rate-limiting step of tryptophan degradation to kynurenine, a reaction strongly induced by IFN-?? through JAK-STAT signaling and further modulated by TNF-??, IL-6, and TGF-??. The resultant tryptophan depletion triggers the GCN2?CeIF2???CATF4 stress pathway, inhibiting T cell proliferation, while kynurenine ligates AhR to drive Treg differentiation. IDO1 requires heme as a cofactor and is subject to proteasomal turnover. Downstream effects also encompass mTORC1 suppression and IL-2 downregulation, collectively fostering an immunosuppressive milieu.
Within the TP53-mutant 143B osteosarcoma background, IDO1 disruption provides a platform to examine the intersection of tumor-driven immune escape and intrinsic stress responses. The loss of IDO1 is expected to relieve tryptophan-dependent T cell inhibition and alter kynurenine-AhR signaling, potentially restoring anti-tumor immunity. This model facilitates studies on how IDO1 cooperates with p53 loss to sustain growth and evade immune surveillance, and can be integrated with mitochondrial dysfunction investigations given the 143B line’s established use in that domain.
Key research applications include tumor immune evasion studies, immune checkpoint inhibitor resistance, and drug screening for IDO1 inhibitors. Representative assays comprise Western blotting for IDO1 protein, RT-qPCR for transcript levels, HPLC-based kynurenine/tryptophan quantitation, flow cytometric analysis of T cell proliferation and Treg markers in co-cultures, and AhR reporter assays. The model also supports investigations into autoimmune diseases, transplantation tolerance, and chronic inflammation. For additional details, please contact Ascent Research.
