Nunc cyrotubes cryoline system internal thread

Each vaccine consisted of 300 μg ARG1: a combination of three 20-amino acid peptides with the sequences: AKDIVYIGLRDVDPGEHYIL (ARG1-18), DVDPGEHYILKTLGIKYFSM (ARG1-19), and KTLGIKYFSMTEVDRLGIGK (ARG1-20) (PolyPeptide, France). 100 μg of each ARG1 peptide was dissolved in sterile water, filtered, and frozen at −20°C in NUNC™ CyroTubes™ CryoLine System Internal Thread, Sigma-Aldrich. A maximum of two hours before administration, peptides were thawed for injection. Shortly before injection, the dissolved peptides were emulsified 1:1 with the adjuvant Montanide ISA-51 (SEPPIC) to a volume of 1 ml. The vaccines were administered subcutaneously every three weeks, repeatedly until reaching a total of 16 vaccines.

Each vaccine was composed of 100 µg IO102, a 21-amino-acid peptide (DTLLKALLEIASCLEKALQVF) from IDO, and 100 µg IO103, a 19-amino-acid peptide (FMTYWHLLNAFTVTVPKDL) from the signal peptide of PD-L1 (PolyPeptide Laboratories). Peptides were dissolved separately in 50 µl DMSO, filtered for sterility and frozen at −20 °C (NUNC CyroTubes CryoLine System Internal Thread, Sigma-Aldrich). At <24 h before administration, peptides were thawed. The PD-L1 peptide was diluted in 400 µl sterile water and, immediately before injection, mixed with the IDO peptide solution and 500 µl Montanide ISA-51 (SEPPIC) to achieve a total volume of 1 ml.