Four human glioma cell lines, U251, H37, D2159 and D270, Fig. 1A, expressed EGFR protein probed by a commercial EGFR antibody with immunofluorescence assay, Fig. 1B. NIR fluorescent labeled EGFR antibody, panitumumab-IRDye800, detected EGFR protein expression in the same cell lines, Fig. 1C. EGFR protein was found on the cytoplasmic membrane of individual cells (Fig. 1B,C insets) with 293 T as negative control. Here, EGFR is linked to glioma.