PTPRC and Platelet storage pool disease: In the blood, the proportion of CD45 + cells identified as M-MDSC were most reduced in the vehicle control group (1.8%) which was significantly lower compared to anti-mCTLA-4 (2.8%; p < 0.01) and combination treatment (3.2%; p < 0.0001), and SPD treatment alone was significantly reduced (p < 0.05) compared to combination treatment (Online Resource Figure S7b).