A. MEF-1 and PEA-13 cells were analyzed for CD91 expression using RT-PCR. All samples were tested for DNA contamination using a paired transcriptase-deficient (RT-) reaction, and were examined for off-target effects to 18S rRNA. B & C. MEF-1 and PEA-13 cells were incubated with 10 μg/mL RAP (B) or 25 μg/mL GRP94.NTD (C), washed, and analyzed by flow cytometry: unstained cells (thin lines), stained cells (bold lines), MEF-1 cells (black lines), and PEA-13 cells (grey lines). D. MEF-1 cells were incubated with 10μg/mL RAP in the absence or presence of 100-fold molar excess unlabeled RAP, GRP94.NTD, or BSA. Cells were then washed and analyzed by flow cytometry: unstained cells (thin grey line), RAP (bold black line), unlabeled RAP (thin black line), unlabeled GRP94.NTD (bold grey line), and unlabeled BSA (shaded grey line). Data presented are representative of three independent replicates.