{"title":"Single-cell transcriptome sequencing reveals the immune microenvironment in bronchoalveolar lavage fluid of checkpoint inhibitor-related pneumonitis.","authors":"Linpeng Zheng, Fenglin Lin, Dingqin Cai, Longyao Zhang, Chenrui Yin, Yaxian Qi, Lingyou Sun, Lingchen Li, Xiewan Chen, Jianbo Zhu, Jianguo Sun","doi":"10.1007/s00262-025-03983-8","DOIUrl":null,"url":null,"abstract":"<p><strong>Background and objectives: </strong>Immune checkpoint inhibitors (ICIs) bring cancer patients tumor control and survival benefits, yet they also trigger immune-related adverse effects (irAEs), notably checkpoint inhibitor-related pneumonitis (CIP), affecting about 5% of patients among whom 1-2% experiencing severe grade 3 or higher pneumonitis. Current research points to potential links with T cell subset dysfunction and autoantibody increase, but the specific mechanisms underlying different grades of CIP are understudied.</p><p><strong>Methods: </strong>Herein, we employed single-cell RNA sequencing (scRNA-seq) on bronchoalveolar lavage fluid (BALF) from CIP patients across varying severity levels, aiming to elucidate underlying immune environment and mechanisms of CIP progression at cellular and molecular levels.</p><p><strong>Findings: </strong>Totally, 121,409 high qualified cells from BALF of 11 patients were annotated and categorized into five major cell types. Severe CIP (CIP-S) cases have a significant increase in the percentage of unreported epithelial cells in their bronchoalveolar lavage fluid compared with mild CIP (CIP-M) cases. These cells were defined as aberrant basaloid cells. They upregulated SOX9, increased the expression of CXCL3/5, recruited neutrophils, and activated the immune system. Additionally, macrophages in the CIP-S group had stronger antigen-presenting abilities and resulted in more CD8 + effective T cells infiltrated.</p><p><strong>Conclusions: </strong>Utilizing single-cell sequencing of BALF, we discovered an enriched population of aberrant basaloid cells in CIP-S patients, which had not been previously reported. Aberrant basaloid cells may upregulate SOX9 via CXCL3/5-CXCR2 to recruit and activate neutrophils, and further activate the immune system, resulting in CIP-S. This finding could identify new targets for stratified treatment of CIP patients, holding promise of a novel approach for clinical guidance.</p>","PeriodicalId":9595,"journal":{"name":"Cancer Immunology, Immunotherapy","volume":"74 4","pages":"128"},"PeriodicalIF":4.6000,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11872840/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cancer Immunology, Immunotherapy","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s00262-025-03983-8","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"IMMUNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background and objectives: Immune checkpoint inhibitors (ICIs) bring cancer patients tumor control and survival benefits, yet they also trigger immune-related adverse effects (irAEs), notably checkpoint inhibitor-related pneumonitis (CIP), affecting about 5% of patients among whom 1-2% experiencing severe grade 3 or higher pneumonitis. Current research points to potential links with T cell subset dysfunction and autoantibody increase, but the specific mechanisms underlying different grades of CIP are understudied.
Methods: Herein, we employed single-cell RNA sequencing (scRNA-seq) on bronchoalveolar lavage fluid (BALF) from CIP patients across varying severity levels, aiming to elucidate underlying immune environment and mechanisms of CIP progression at cellular and molecular levels.
Findings: Totally, 121,409 high qualified cells from BALF of 11 patients were annotated and categorized into five major cell types. Severe CIP (CIP-S) cases have a significant increase in the percentage of unreported epithelial cells in their bronchoalveolar lavage fluid compared with mild CIP (CIP-M) cases. These cells were defined as aberrant basaloid cells. They upregulated SOX9, increased the expression of CXCL3/5, recruited neutrophils, and activated the immune system. Additionally, macrophages in the CIP-S group had stronger antigen-presenting abilities and resulted in more CD8 + effective T cells infiltrated.
Conclusions: Utilizing single-cell sequencing of BALF, we discovered an enriched population of aberrant basaloid cells in CIP-S patients, which had not been previously reported. Aberrant basaloid cells may upregulate SOX9 via CXCL3/5-CXCR2 to recruit and activate neutrophils, and further activate the immune system, resulting in CIP-S. This finding could identify new targets for stratified treatment of CIP patients, holding promise of a novel approach for clinical guidance.
期刊介绍:
Cancer Immunology, Immunotherapy has the basic aim of keeping readers informed of the latest research results in the fields of oncology and immunology. As knowledge expands, the scope of the journal has broadened to include more of the progress being made in the areas of biology concerned with biological response modifiers. This helps keep readers up to date on the latest advances in our understanding of tumor-host interactions.
The journal publishes short editorials including "position papers," general reviews, original articles, and short communications, providing a forum for the most current experimental and clinical advances in tumor immunology.