Sodium stibogluconate

99.1% pure TCDD dissolved in dimethyl sulfoxide (DMSO) was purchased from AccuStandard Inc., (New Haven, CT). Tissue culture grade DMSO was purchased from Sigma Aldrich (St. Louis, MO). Sodium Stibogluconate (SSG) (EMD Millipore, Billerica, MA) also known as sodium antimony gluconate is a potent inhibitor of SHP-1 phosphatase (Pathak and Yi, 2001 ) and was used at a final concentration of 10µg/ml in vitro. SSG was dissolved in water at 70°C and was freshly prepared for all experiments involving the inhibitor.

The SHP-1 inhibitor sodium stibogluconate (SSG) was purchased from EMD Millipore (567565). Two different inhibitors of DGK were purchased from Sigma (DGKinh1 (nonspecific inhibitor), D5919; DGKinh2 (alpha isoform specific), D5794). Functional antibody against PD-L1 was a generous gift from Dr. Gordan Freeman. ^{29 (link)} Human IL2 (Proleukin, Prometheus) was acquired through the Hospital of the University of Pennsylvania pharmacy. Dose response curves were performed for both DGK inhibitors and for SSG, and the highest doses which did not induce direct tumor cell killing were used. 1uM of both DGK inhibitors and 25ug/ml of SSG were also demonstrated to be appropriate in other published investigations. ^{30 (link), 31 (link)} All inhibitory studies were done twice in independent fashion with comparable results.