Tryptophan Catabolism as Immune Mechanism of Primary Resistance to Anti-PD-1

Conclusion: Serum kyn/trp ratio could have both prognostic and predictive values in patients with solid tumor treated with immunotherapy, probably reflecting a primary immune-resistant mechanism regardless of the primary tumor histology. Its relative weight is significantly related to gender, site of metastasis, NSCLC, and squamous histology, although these suggestive data need to be confirmed in larger studies.
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research