indolamine-2,3-dioxygenase

initialism: IDO
https://doi.org/10.1351/goldbook.13329
Enzyme catalyzing the initial rate-limiting step of tryptophan degradation.
Note: Tryptophan is required for T-cell proliferation. Local degradation of tryptophan thus modulates T-cell activity.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1193 [Terms] [Paper]