Various whole cell extracts (30 μg) were separated by 10% SDS-PAGE, and the membrane was blotted with SIRP alpha antibody [HL3149] (GTX640659) diluted at 1:1000. The HRP-conjugated anti-rabbit IgG antibody (GTX213110-01) was used to detect the primary antibody. Corresponding RNA expression data for the same cell lines are based on Human Protein Atlas program.