CD274 and myeloproliferative disorder: To determine the expression levels of PD‐L1 and PD‐L2 in MPN cells, we analyzed the whole‐transcriptome RNA‐sequencing data set of a well‐characterized cohort of 104 patients with chronic phase MPN, 9 patients with post‐MPN sAML, and 14 healthy controls (Figures 1A,B and S1,2).27