Monoclonal antibody protocol for CTLA-4 and PD-L1

The following antibodies were used: anti-CTLA-4 ipilimumab mAb (Yervoy, Bristol Myers Squibb, NY, USA), anti-PD-L1 Atezolizumab mAb (InvivoGen, San Diego, CA, USA); commercial human anti-PD-L1 (G&P Biosciences, Santa Clara, CA, USA) and anti-CTLA-4 (R&D Systems, Minneapolis, MN, USA) Abs; anti-human IgG (H+L) HRP-conjugated Ab (Promega, Madison, WI, USA); anti-human IgG (Fab’)2 goat HRP-conjugated monoclonal antibody (Abcam, Biomedical Campus, Cambridge, UK).
ID-1 (anti-CTLA-4) and PD-L1_1 (anti-PD-L1) mAbs were produced and purified, as previously described [32 (link),33 (link),34 (link),35 (link)], taking advantage of the enhanced cell line HEK293_ES1 expressing a long non-coding SINEUP RNA [36 (link),37 (link)].