PD-L1 expression in melanoma: A quantitative immunohistochemical antibody comparison

Joel C. Sunshine, Peter L. Nguyen, Genevieve J. Kaunitz, Tricia R. Cottrell, Sneha Berry, Jessica Esandrio, Haiying Xu, Aleksandra Ogurtsova, Karen B. Bleich, Toby C. Cornish, Evan J. Lipson, Robert A. Anders, Janis M. Taube

Research output: Contribution to journalArticlepeer-review

Abstract

Purpose: PD-L1 expression in the pretreatment tumor microenvironment enriches for response to anti-PD-1/PD-L1 therapies. The purpose of this study was to quantitatively compare the performance of five monoclonal anti-PD-L1 antibodies used in recent landmark publications. Experimental Design: PD-L1 IHC was performed on 34 formalin-fixed paraffin-embedded archival melanoma samples using the 5H1, SP142, 28-8, 22C3, and SP263 clones. The percentage of total cells (including melanocytes and immune cells) demonstrating cell surface PD-L1 staining, as well as intensity measurements/H-scores, were assessed for each melanoma specimen using a computer-assisted platform. Staining properties were compared between antibodies. Results: Strong correlations were observed between the percentage of PD-L1(þ) cells across all clones studied (R2 = 0.81–0.96). When present, discordant results were attributable to geographic heterogeneity of the melanoma tissue section rather than differences in PD-L1 antibody staining characteristics. PD-L1 intensity/H-scores strongly correlated with percentage of PD-L1(þ) cells (R2 > 0.78, all clones). Conclusions: The 5H1, SP142, 28-8, 22C3, and SP263 clones all demonstrated similar performance characteristics when used in a standardized IHC assay on melanoma specimens. Reported differences in PD-L1 IHC assays using these antibodies are thus most likely due to assay characteristics beyond the antibody itself. Our findings also argue against the inclusion of an intensity/H-score in chromogenic PD-L1 IHC assays.

Original languageEnglish (US)
Pages (from-to)4938-4944
Number of pages7
JournalClinical Cancer Research
Volume23
Issue number16
DOIs
StatePublished - Aug 15 2017

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint Dive into the research topics of 'PD-L1 expression in melanoma: A quantitative immunohistochemical antibody comparison'. Together they form a unique fingerprint.

Cite this