ArticleMethods in enzymology2019
Quantification of IDO1 enzyme activity in normal and malignant tissues.
Article in Methods in enzymology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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Who cites it
13 citing papers in PubMed, 21 citations in OpenAlex.
- Tryptophan metabolism in tumor microenvironment and therapeutic implications.Journal of advanced research · 2026Review
- Modulating IDO1 and TDO Inhibition Through Structural Modification of Diaryl Hydroxylamines.ChemMedChem · 2026Article
- Electrochemical Analysis and Inhibition Assay of Immune-Modulating Enzyme, Indoleamine 2,3-Dioxygenase.Pharmaceuticals (Basel, Switzerland) · 2025Article
- Rational Design and Optimization of a Potent IDO1 Proteolysis Targeting Chimera (PROTAC).Journal of medicinal chemistry · 2025Article
- Cytokine priming enhances the antifibrotic effects of human adipose derived mesenchymal stromal cells conditioned medium.Stem cell research & therapy · 2024Article
- Low indoleamine 2, 3 dioxygenase (IDO) activity is associated with psycho-obstetric risk.Pregnancy hypertension · 2024Article
- The tryptophan-kynurenine pathway in immunomodulation and cancer metastasis.Cancer medicine · 2023Review
- Beyond CTLA-4 and PD-1 Inhibition: Novel Immune Checkpoint Molecules for Melanoma Treatment.Cancers · 2023Review
- L-Kynurenine participates in cancer immune evasion by downregulating hypoxic signaling in T lymphocytes.Oncoimmunology · 2023Article
- Identification and Characterization of a Novel Indoleamine 2,3-Dioxygenase 1 Protein Degrader for Glioblastoma.Journal of medicinal chemistry · 2022Article
- Unbalanced IDO1/IDO2 Endothelial Expression and Skewed Keynurenine Pathway in the Pathogenesis of COVID-19 and Post-COVID-19 Pneumonia.Biomedicines · 2022Review
- Reliable chromatographic assay for measuring of indoleamine 2,3-dioxygenase 1 (IDO1) activity in human cancer cells.Journal of enzyme inhibition and medicinal chemistry · 2021Article
- Association of serum kynurenine/tryptophan ratio with poor glycemic control in patients with type2 diabetes.Journal of diabetes and metabolic disorders · 2021Article
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Authors and funding
8 authors at 2 institutions in 1 country.
Funding
Abstract
Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first and rate-limiting reaction of l-tryptophan (Trp) conversion into l-kynurenine (Kyn). The depletion of Trp, and the accumulation of Kyn have been proposed as mechanisms that contribute to the suppression of the immune response-primarily evidenced by in vitro study. IDO1 is therefore considered to be an immunosuppressive modulator and quantification of IDO1 metabolism may be critical to understanding its role in select immunopathologies, including autoimmune- and oncological-conditions, as well as for determining the potency of IDO1 enzyme inhibitors. Because tryptophan 2,3-dioxygenase (TDO), and to a significantly lesser extent, IDO2, also catabolize Trp into Kyn, it's important to differentiate the contribution of each enzyme to Trp catabolism and Kyn generation. Moreover, a great variety of detection methods have been developed for the quantification of Trp metabolites, but choosing the suitable protocol remains challenging. Here, we review the differential expression of IDO1/TDO/IDO2 in normal and malignant tissues, followed by a comprehensive analysis of methodologies for quantifying Trp and Kyn in vitro and in vivo, with an emphasis on the advantages/disadvantages for each application.
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Registered trials
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