L kynurenine l kyn

Peptides used in this investigation (Table 1) were >95% pure. They were generously provided by Drs. Jack Bennink and Jonathan Yewdell (National Institutes of Health). Stock solutions of all peptides were prepared at 1 mM in DMSO and stored at −30°C. Each peptide was used at a final concentration of 500 nM in our assays. 1-Methyl-D-tryptophan (1-D-MT) was purchased from Sigma (Mississauga, ON). The powder was dissolved at 5 mg/mL in 0.1 M NaOH followed by drop-wise addition of 12 M HCl to generate a neutral solution, which was then filter-sterilized and injected as indicated. L-kynurenine (L-Kyn), also from Sigma, was dissolved at 10 mg/mL in PBS shortly before injection.

L-Kynurenine (L-Kyn) was purchased from Sigma (K8625), dissolved in DMSO, and used at 100μM. Cyclosporin A was purchased form Selleckchem (S2286), dissolved in DMSO, and used at 300nM. FK506 was purchased from Selleckchem (S5003) resuspended in DMSO, and used at 300nM. Anti-IgG (Sigma I5260) was used at 10μg/mL for 30 minutes to overnight. Control conditions were treated with equal amounts of DMSO.