Fig. 5
Analysis of programmed death ligand 1 (PD-L1) protein expression in patient-derived xenograft (PDX) tumor samples engrafted in both nonhumanized and humanized nonobese diabetic/severe combined immunodeficiency IL2Rγnull (hNSG) mice performed by Western blotting (a, MC1) or IHC (b, upper panels, MC1; lower panels, BCM-4913). In Western blotting experiments, samples were blotted with an anti-β-actin antibody as a loading control. The blots were processed in parallel, and they were all sourced from the same experiment. c Comparative analysis of PD-L1 levels was performed using four different PDX tumor lines (MC1, BCM-4913, BCM-4664, BCM-5471) engrafted in hNSG mice. Three independent tumors (animals) of each PDX line were evaluated by Western blot analysis. Samples were blotted with an anti-β-actin antibody as a loading control. d PD-L1 analysis performed by IHC of BCM-4664 and BCM-5471 PDXs engrafted in hNSG mice. 4× magnifications are shown; counterstain, hematoxylin