The clear path to small molecule visualization & quantification

Contact Distributors

“Kynurenine/Kynurenic Acid/Quinolinic Acid ELISA pack (3-KYNs ELISA pack)” has been added to your cart. View cart

kynurenine tryptophan ratio ELISA kit ISE-2227

Kynurenine/Tryptophan ratio ELISA in IDOi-treated micePlasma samples were collected from MCA205 tumor-bearing mice treated with either vehicle or IDO inhibitor (GDC-0919) and determination of kynurenine to tryptophan ratio (KTR)

L-Kynurenine/ L-Tryptophan ratio ELISA in CT26 tumor cell linesMurine CT26 colorectal cancer cell line was modified to stably express indoleamine 2,3 dioxygenase (IDO1). Its empty-vector counterpart cell-line (Mock) was used as a negative control for the transfection, while WT was the parental CT26 cell line. These different cell lines were cultured in 24-well plates for 48 hours. Kynurenine and Tryptophan were then measured with dedicated ELISA kits and KTR ratio.

Kynurenine / Tryptophan in cell culture supernatantsMature human dendritic cells (mDCS) were cultured together with HLA-mismatched CD4+ T cells (mixed lymphocyte reaction context) and exposed for 72 hours with increasing concentrations of a reference IDO1 inhibitor. Supernatants were then collected for kynurenine and tryptophan content measurement by mean of ELISA (ISE-2227 Kynurenine/tryptophan ELISA pack). Kynurenine content (through KTR) is dose-dependently decreased by IDO inhibition.

Kynurenine – Tryptophan ELISA standard curves

Key features

Sample type	Plasma, Serum, Cell culture supernatant, Urine
Capacity	2 x 96 tests
Sensitivity	LoD KYN: < 47.5 ng/mL LoD TRP: < 1.2 µg/mL
Range	KYN: 0/100 – 10 000 ng/mL TRP: 2.5 – 250 µg/mL
Assay time	Sample preparation (90-135 min), ELISA overnight
Reactivity	Reacts with all species
Application	Research use only or IVD (EU only)

Citations

2025 Fernández-Pinteño et al., - Age-Related Changes in Gut Health and Behavioral Biomarkers in a Beagle Dog Population, Animals, Species : Dog ; Sample type : Serum ;
2025 Lim et al., - Single-cell transcriptomics of bronchoalveolar lavage during PRRSV infection with different virulence, Nat Commun., Species : Pig ; Sample type : Serum ;
2025 Ueda et al., - Tryptophan-sensing receptor GPR142 expression levels are directly regulated by proinflammatory cytokines in ghrelin-producing cells, FEBS Open Bio. , Species : Human ; Sample type : Plasma ;
2025 Zurmühl et al., - The role of peripheral blood dendritic cell subsets in the house dust mite-allergic immune response, Dissertation, Species : Human ; Sample type : Serum ;
2025 Nas et al., - Sodium benzoate may reduce appetite in Drosophila melanogaster through serotonin upregulation, Arch Biol Sci, Species : Insects ; Sample type : Whole animal ;
2024 Wang Z. et al., - Camptothesome-based combination nanotherapeutic regimen for improved colorectal cancer immunochemotherapy, Biomaterials, Species : Mouse ; Sample type : Plasma ;
2024 Shu G. et al, - PABPC1L induces IDO1 to promote tryptophan metabolism and immune suppression in renal cell carcinoma, Cancer Res, Species : Human ; Sample type : Cell culture supernatant ;
2024 Vaughan et al., - Derangements of immunological proteins in HIV-associated diffuse large B-cell lymphoma: the frequency and prognostic impact, Front. Cell. Infect. Microbiol., Species : Human ; Sample type : Serum ;
2024 Gillies et al., - Effects of a flavonoid-rich blackcurrant beverage on markers of the gut-brain axis in healthy females: Secondary findings from a 4-week randomized crossover control trial., Current Developments in Nutrition, Species : Human ; Sample type : Serum ;
2024 Fongsaran C. et al., - VEEV TC-83 Triggers Dysregulation of the Tryptophan–Kynurenine Pathway in the Central Nervous System That Correlates with Cognitive Impairment in Tg2576 Mice, Pathogens, Species : Mouse ; Sample type : Brain ;
2024 Valera et al., - Surface-Enhanced Raman Scattering Monitoring of Tryptophan Dynamics in 3D Pancreatic Tumor Models, ACS Sensors, Species : Human ; Sample type : Organoid ;
2024 Dellink et al., - Continuous theta burst stimulation for bipolar depression: A multicenter, double-blind randomized controlled study exploring treatment efficacy and predictive potential of kynurenine metabolites, Journal of Affective Disorders, Species : Human ; Sample type : Plasma ;
2024 Ros-Lucas et al., - Transcriptomic evidence of immune modulation in subjects with chronic Trypanosoma cruzi infection, J Infect Dis., Species : Human ; Sample type : PBMC ;
2024 Choi et al., - Light-Triggered PROTAC Nanoassemblies for Photodynamic IDO Proteolysis in Cancer Immunotherapy, Adv Mater., Species : Human ; Sample type : Cell culture ;
2024 Gliozzi M et al., - The dangerous “West Coast Swing” by hyperglycaemia and chronic stress in the mouse hippocampus: Role of kynurenine catabolism, Pharmacological Research, Species : Mouse ; Sample type : Serum ;
2023 Das et al., - Citrulline and kynurenine to tryptophan ratio: potential EED (environmental enteric dysfunction) biomarkers in acute watery diarrhea among children in Bangladesh, Scientific Reports, Species : Human ; Sample type : Plasma ;
2023 Mrstna et al., - Advances in kynurenine analysis, Clinica Chimica Acta, Species : Human ; Sample type : Plasma ;
2023 Mystakeli et al., - An open label randomized controlled trial of atorvastatin versus aspirin in elite controllers and antiretroviral-treated people with HIV, AIDS, Species : Human ; Sample type : Plasma ;
2023 Kaneko Y. et al, - Pathogenetic associations of anti-ribosomal P protein antibody titres and their subclasses in patients with systemic lupus erythematosus, Rheumatology (Oxford), Species : Human ; Sample type : Serum ;
2023 Munoz et al., - Effects of Supplementation with the Standardized Extract of Saffron (affron®) on the Kynurenine Pathway and Melatonin Synthesis in Rats, Antioxydants, Species : Rat ; Sample type : Serum ;
2023 Lysandrou et al., - Hypomethylation-induced regulatory programs in T cells unveiled by transcriptomic analyses, Frontiers in Immunology, Species : Human ; Sample type : Cell culture supernatant ;
2023 Wang et al., - Sphingomyelin-derived nanovesicles for the delivery of the IDO1 inhibitor epacadostat enhance metastatic and post-surgical melanoma immunotherapy, Nat Commun., Species : Mouse ; Sample type : Tumor tissues ;
2023 Onning et al., - Intake of Lactiplantibacillus plantarum HEAL9 Improves Cognition in Moderately Stressed Subjects: A Randomized Controlled Study, Nutrients, Species : Human ; Sample type : Plasma ;
2023 Letenneur et al., - Effects of a Lacticaseibacillus Mix on Behavioural, Biochemical, and Gut Microbial Outcomes of Male Mice following Chronic Restraint Stress, Nutrients, Species : Mouse ; Sample type : Serum ;
2023 Dongen et al., - Atheroma plaque microenvironment stimulates kynurenine production by macrophages to induce endothelial adhesion molecules in the context of atherogenesis, bioRxiv, Species : Human ; Sample type : Plasma ;
2023 Mougin et al., - Dietary Marine Hydrolysate Improves Memory Performance and Social Behavior through Gut Microbiota Remodeling during Aging, Foods, Species : Mouse ; Sample type : Plasma ;
2023 Yoshioka S., - Discovery of a novel dual inhibitor of IDO1 and TDO by phenotypic screening, Doctoral Thesis, Species : ; Sample type : ;
2023 Girithar et al., - Involvement of the kynurenine pathway in breast cancer: updates on clinical research and trials, British Journal of Cancer, Species : Human ; Sample type : Plasma ;
2023 Silvano et al., - Tryptophan degradation enzymes expression in the placenta and the Kynurenine/Tryptophan ratio in maternal plasma after elective cesarean section, Journal of Reproductive Immunology, Species : Human ; Sample type : Plasma ;
2022 Lischka et al., - Tryptophan Metabolism Is Associated with BMI and Adipose Tissue Mass and Linked to Metabolic Disease in Pediatric Obesity, Nutrients, Species : Human ; Sample type : Plasma ;
2022 Struckmeier et al., - IDO1 is highly expressed in macrophages of patients in advanced tumour stages of oral squamous cell carcinoma, J of cancer research & clinical oncology, Species : Human ; Sample type : Blood ;
2022 Sugisawa et al., - Nociceptor-derived Reg3γ prevents endotoxic death by targeting kynurenine pathway in microglia, Cell reports, Species : Mouse ; Sample type : Brain ;
2021 Francikowski et al., - The effects of high-monosaccharide diets on development and biochemical composition of white-eyed mutant strain of house cricket (Acheta domesticus), Scientific reports, Species : Insects ; Sample type : Hemolymph ;
2021 Adu-Gyamfi et al., - Plasma Kynurenine-to-Tryptophan Ratio, a Highly Sensitive Blood-Based Diagnostic Tool for Tuberculosis in Pregnant Women Living With Human Immunodeficiency Virus (HIV), Clinical Infectious Diseases, Species : Human ; Sample type : Plasma ;
2021 Wang et al., - Abnormal Tryptophan Metabolism in HIV and Mycobacterium tuberculosis Infection, Front Microbiol., Species : Monkey ; Sample type : Plasma ;
2021 MacDowell et al., - Paliperidone Reversion of Maternal Immune Activation-Induced Changes on Brain Serotonin and Kynurenine Pathways, Frontiers in Pharmacology, Species : Mouse ; Sample type : Brain ;
2021 Wood et al., - Apathy is not associated with a panel of biomarkers in older adults with HIV disease, J of Psychosomatic Research, Species : Human ; Sample type : Plasma ;
2021 Pospíšková et al., - Circulating concentrations of citrulline, neopterin, kynurenine, and tryptophan during chemoradiation in patients with cervical carcinoma, Pteridines, Species : Human ; Sample type : Plasma ;
2021 Kim et al., - Deep learning model enables the discovery of a novel immunotherapeutic agent regulating the kynurenine pathway, OncoImmunology, Species : Mouse ; Sample type : Tumor tissues ;
2021 Eleftheriadis et al., - The Role of Indoleamine 2,3-Dioxygenase in Renal Tubular Epithelial Cells Senescence under Anoxia or Reoxygenation, Biomolecules, Species : Mouse ; Sample type : Cell culture supernatant ;
2021 Jung Cho et al., - Decreased IDO1-dependent tryptophan metabolism in aged lung during influenza, European Respiratory Journal, Species : Human ; Sample type : Cell culture supernatant ;
2020 Baumgartner et al., - Evidence that a deviation in the kynurenine pathway aggravates atherosclerotic disease in humans, Journal of Internal Medicine, Species : Human ; Sample type : Plasma ;
2020 Adu-Gyamfi et al., - Diagnostic accuracy of plasma kynurenine/tryptophan ratio, measured by enzyme-linked immunosorbent assay, for pulmonary tuberculosis, International Journal of Infectious Diseases, Species : Human ; Sample type : Plasma ;
2020 Bekki et al. , - Serum kynurenine levels are a novel biomarker to predict the prognosis of patients with hepatocellular carcinoma, PLoS One, Species : Human ; Sample type : Serum ;
2020 Nafia et al., - IDO Targeting in Sarcoma: Biological and Clinical Implications, Front. Immunol, Species : Human ; Sample type : Cell culture ;
2020 Nimii et al., - Effect of repetitive transcranial magnetic stimulation on the kynurenine pathway in stroke patients, Neuroreport. , Species : Human ; Sample type : Serum ;
2020 Watanabe et al., - Adding Indoximod to Hypofractionated Radiotherapy with Anti-PD-1 Checkpoint Blockade Enhances Early NK and CD8+ T-Cell-Dependent Tumor Activity, Clinical Cancer Research, Species : Human ; Sample type : Cell culture supernatant ;
2020 Walker et al., - Leucine competes with kynurenine for blood-to-brain transport and prevents lipopolysaccharide-induced depression-like behavior in mice, Molecular Psychiatry, Species : Mouse ; Sample type : Brain ;
2020 Muller-Thomas et al., - Prognostic value of indoleamine 2,3 dioxygenase in patients with higher-risk myelodysplastic syndromes treated with azacytidine, British Journal of Haematology, Species : Human ; Sample type : Cell culture ;
2019 Agullo-Ortuno et al., - Blood Predictive Biomarkers for Patients With Non-small-cell Lung Cancer Associated With Clinical Response to Nivolumab, Clinical Lung Cancer, Species : Human ; Sample type : Plasma ;
2018 Ziklo et al., - Dysbiosis of the Vaginal Microbiota and Higher Vaginal Kynurenine/Tryptophan Ratio Reveals an Association with Chlamydia trachomatis Genital Infections, Front. Cell. Infect. Microbiol, Species : Human ; Sample type : Cervical secretion ;
2018 Martiin-Hernandez et al., - Chronic Mild Stress Alters Kynurenine Pathways Changing the Glutamate Neurotransmission in Frontal Cortex of Rats, Molecular Neurobiology, Species : Rat ; Sample type : Brain ;
2018 Zhang et al., - Traumatic Injury Leads to Inflammation and Altered Tryptophan Metabolism in the Juvenile Rabbit Brain, Journal of Neurotrauma, Species : Rabbit ; Sample type : Brain ;
2018 Gautam et al., - In vivo inhibition of tryptophan catabolism reorganizes the tuberculoma and augments immune-mediated control of Mycobacterium tuberculosis, Proc Natl Acad Sci U S A, Species : Monkey ; Sample type : Lung ;
2017 Toulmonde et al., - Use of PD-1 Targeting, Macrophage Infiltration, and IDO Pathway Activation in Sarcomas: A Phase 2 Clinical Trial, JAMA Oncology, Species : Human ; Sample type : Plasma ;
2017 Perez Guzman et al., - The Functional Relationship Between The Gut Microbiota And Generalized Anxiety Disorder in The Murine Model, Thesis - McMaster University, Species : Mouse ; Sample type : Serum ;

Frequently asked questions

ISE-2227R

Kynurenine to Tryptophan ratio ELISA pack

This Kynurenine to Tryptophan ratio ELISA pack provides a reliable, quantitative method for measuring tryptophan catabolism via the kynurenine pathway across a large number of samples. The pack includes two ready-to-use, highly sensitive kits that require only 20 µL of sample per test. Compatible with any species, the kit allows the performance of longitudinal studies in small animals, such as mice.

€1049 ~~€1198~~

Number of citations :

Pay by online or by purchase order

Pay by credit/debit card or generate a quote at checkout (your products will be sent once you provide us with the purchase order)

Fast Worldwide Shipping with Fedex

We ship your order door-to-door in all countries with FedEx International Priority^®.

Worry-free Warranty

Made a mistake ordering ? 30-day free return & refund.

Product damaged during shipping ? Free replacement.

Not getting satisfactory results ? If product did not meet quality standards, customer support offers replacement or refund.

Direct Customer Support

For questions, protocol recommendations, and troubleshooting, you have direct access to the scientist that developed the antibody or ELISA kit you’re using.

Direct customer support is available all business days.

A knowledge base containing protocols, Frequently Asked Questions, and troubleshooting tips is also available online.

They published with this product

Johns Hopkins University School f Medicine

Niigata University Graduate School of Medical and Dental Sciences

The University of Texas MD Anderson Cancer Center

L-Tryptophan Antibody – Mouse Monoclonal

Used for IF in rodent brain & renal tissues, and human cell cultures. Cited in…

€449

-17%

Kynurenine/Kynurenic Acid/Quinolinic Acid ELISA pack (3-KYNs ELISA pack)

KYN / KYNA / QA ELISA pack - Standard curves

Add to cart / quote

ELISA kits

Kynurenine/Kynurenic Acid/Quinolinic Acid ELISA pack (3-KYNs ELISA pack)

High Sensitivity. Plasma, Serum. Min. Vol. 25-50µL. Cited in literature

€1499~~€1797~~

Immunohistochemical analysis reveals accumulation of L-Kynurenine within tumor cells of human colorectal cancer (CRC) tissue.

Add to cart / quote

Antibodies

L-Kynurenine Antibody – Mouse Monoclonal

Used for IF & IHC in brain, heart, and tumor tissues I Cited in 10+…

€449

L-Kynurenine accumulation in human colorectal tumor by IHC

Add to cart / quote

Antibodies

L-Kynurenine Antibody – Rabbit Polyclonal

Used for IHC in FFPE lung & tumor tissues. Cited in literature

€449

L-tryptophan ELISA kit high sensitive any sample

Select options

Amino acids

L-Tryptophan ELISA kit

High sensitivity, biological fluids (≥ 20µL), cited in 50+ papers

€599

L-kynurenine ELISA kit assay immusmol BA-E-2200

Determination of L-Kynurenine levels in cell cultures through microdialysis collection and by ELISA quantification

Select options

ELISA kits

L-Kynurenine ELISA kit

High Sensitivity, biological fluids (≥ 20µL), cited in 68 papers

€599

ISE-2227R

Kynurenine to Tryptophan ratio ELISA pack

Kyrurenine to Tryptophan ELISA pack composed of :

– BA-E-2200 – Kynurenine ELISA kit – Research test for the detection of L-Kynurenine (RUO or IVD)
– BA-E-2700 – Tryptophan ELISA kit – Research test for the detection of L-Tryptophan (RUO or IVD)

Specifications

Product name	Kynurenine/Tryptophan ratio ELISA pack – composed of 1 x BA-E2200 kit and 1 x BA-E-2700 kit
Description	Two enzyme immunoassays (ELISA) allowing the quantitative determination of L-Kynurenine to L-Tryptophan ratio in urine, plasma and serum samples
Format	2x 96-well plates
Samples	Plasma, serum, Cell culture supernatant, Urine
Minimal sample volume	20µL
Reactivity	Reacts with all species
Standard range	KYN: 0/100 – 10 000 ng/mL TRP: 2.5 – 250 µg/mL
Sensitivity	LoD KYN: < 47.5 ng/mL LoD TRP: < 1.2 µg/mL
Specificity	No significant cross-reactivity was observed with L-Tryptophan and L-Kynurenine analogs. See product pages for L-Kynurenine ELISA and L-Tryptophan ELISA
Assay time	Sample preparation (90min- 2h15min), Serum incubation overnight, revelation and read steps (1h)

Instructions

Storage	Store at 2-8°C for up to 6 months
Sample collection & storage	Plasma/Serum: EDTA-, Heparin- or Citrate- samples stored at 2-8°C for up to 48h, or -20°C for longer period (up to 6 months)
Sample preparation	KYN: Sample acylation (90 min) TRP: Sample precipitation (15 min) and derivatization (2h)
ELISA	Antiserum overnight incubation, revelation and read steps (1h)