Localization of PD‐L1 on single cancer cells by iSERS microscopy with Au/Au core/satellite nanoparticles

• Published in: Journal of biophotonics 2020-03, Vol.13 (3), p.e201960034-n/a
• Main Authors: Stepula, Elzbieta, König, Matthias, Wang, Xin‐Ping, Levermann, Janina, Schimming, Tobias, Kasimir‐Bauer, Sabine, Schilling, Bastian, Schlücker, Sebastian
• Format: Article
• Language: English
• Subjects: Antibodies; Apoptosis; Biomarkers; Cancer; Cell death; Excitation; Full; Gold; gold nanoparticles; Image processing; Immunotherapy; Infrared lasers; Localization; Microscopy; Nanoparticles; PD-L1 protein; PD‐L1; Raman; SERS
• ISSN: 1864-063X; 1864-0648
• DOI: 10.1002/jbio.201960034

Programmed cell death‐ligand 1 (PD‐L1) is an important predictive biomarker. The detection of PD‐L1 can be crucial for patients with advanced cancer where the use of immunotherapy is considered. Here, we demonstrate the use of immuno‐SERS microscopy (iSERS) for localizing PD‐L1 on single cancer SkBr‐3 cells. A central advantage of iSERS is that the disturbing autofluorescence from cells and tissues can be efficiently minimized by red to near‐infrared laser excitation. In this study we employed Au/Au core/satellite nanoparticles as SERS nanotags because of their remarkable signal brightness and colloidal stability upon red laser excitation. False‐color iSERS images of the positive and negative controls clearly reveal the specific localization of PD‐L1 with SERS nanotag‐labeled antibodies. iSERS (SERS=surface‐enhanced Raman scattering) microscopy is an emerging Raman‐based staining technique for the selective localization of target proteins on cells and tissues using antibody‐SERS nanotag conjugates. In this contribution we demonstrate the feasibility of iSERS for imaging of programmed cell deathligand 1 (PD‐L1), an important predictive biomarker, on single SkBr‐3 breast cancer cells.