Autoimmunity Against Surfactant Protein B Is Associated with Pneumonitis During Checkpoint Blockade.

RATIONALE: Immune checkpoint inhibitor-related pneumonitis is a serious autoimmune event affecting up to 20% of patients with non-small cell lung cancer, yet the factors underpinning its development in some patients and not others are poorly understood. OBJECTIVES: To investigate the role of autoantibodies and autoreactive T cells against surfactant-related proteins in the development of pneumonitis. METHODS: The study cohort consisted of non-small cell lung cancer patients who gave blood samples before and during immune checkpoint inhibitor treatment. Serum was used for proteomics analyses and to detect autoantibodies present during pneumonitis. T cell stimulation assays and single-cell RNA sequencing were performed to investigate the specificity and functionality of peripheral autoreactive T cells. The findings were confirmed in a validation cohort comprising patients with non-small cell lung cancer and patients with melanoma. MEASUREMENTS AND MAIN RESULTS: Across both cohorts, patients who developed pneumonitis had higher pre-treatment levels of immunoglobulin G autoantibodies targeting surfactant protein-B. At the onset of pneumonitis, these patients also exhibited higher frequencies of CD4+ interferon-gamma-positive surfactant protein B-specific T cells, and expanding T cell clonotypes recognizing this protein, accompanied by a pro-inflammatory serum proteomic profile. CONCLUSIONS: Our data suggest that the co-occurrence of surfactant protein-B-specific immunoglobulin G autoantibodies and CD4+ T cells is associated with the development of pneumonitis during ICI therapy. Pre-treatment levels of these antibodies may represent a potential biomarker for elevated risk of developing pneumonitis and on-treatment levels may provide a diagnostic aid. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Clinicopathological characterization of next-generation sequencing detected mutations in lung cancers-a single-center experience.

Background: Despite many advances in molecular procedures many lung cancer patients do not receive full panel testing. This can limit the comprehensive understanding of their disease and potentially hinder personalized treatment options. Methods: In this retrospective analysis, we used results from next-generation sequencing (NGS) testing of 154 patients with adenocarcinoma (AC) or squamous cell carcinoma (SCC) of the lung treated at the University Hospital, Ludwig-Maximilians Universität (LMU) Munich between 2018 and 2021. We compared different clinicopathological features and patients' baseline characteristics with results of NGS testing. We used t-test and analysis of variance (ANOVA) to compare metric- and χ2-test and Fisher's exact test to compare categorical variables. Results: NGS testing found mutations in 107 (69.5%) patients; 44 patients (28.6%) had more than one mutation. The majority (79.2%) of patients had AC and 64.9% were metastasized at diagnosis. Patients with detected mutations had significantly higher PD-L1 expression than those without mutations (36.4% vs. 19.2%, P=0.005). Mean PD-L1 expression also differed between different mutations ranging from 24.0% in EGFR to 56.8% in patients with MET alterations, and increased with the number of different mutations (P=0.07). EGFR mutations were significantly more common in females compared to males (22.9% vs. 9.5%, P=0.04) and PIK3CA mutations significantly more common in SCC (21.9% vs. 2.5%, P=0.004). We found 23 different mutations in AC and 13 different gene mutations in SCC. Conclusions: Mutation profiles differed by histological type and metastases status and were significantly associated with PD-L1 expression. In the context of limited resources, our results may help prioritize patient for testing when tissue material and funding is limited.