Journal Article

P251 Investigation of myeloid-derived suppressor cells as a biomarker for the differential diagnosis of lung diseases

Symvoulaki, K, Apostolidou, A, Liapikou, A, Bizymis, A P, Antoniou, K M, Matthaiou, A M, Tomos, I, Tzanakis, N, Bizymi, N, Pitsidianakis, G

2025

Overview

Introduction and ObjectivesMyeloid-derived suppressor cells (MDSCs) are immature cells with immunosuppressive properties, divided into polymorphonuclear (PMN-) and monocytic (M-) subpopulations. Based on a limited number of disease-specific studies, they appear to be involved in a wide spectrum of lung diseases. We aimed to standardise a simple measuring protocol of MDSCs in the lungs and the systemic circulation and to comparatively investigate their differences among distinct lung diseases.MethodsIn 16 patients with lung diseases, MDSCs were measured in peripheral blood (PB) and bronchoalveolar lavage (BAL) via flow cytometry and immunophenotypically defined as CD45+CD3−CD19−CD20−CD56−CD16−HLA-DR−CD33+CD11b+CD15+Lox-1+ PMN-MDSCs and CD45+CD3−CD19−CD20−CD56−CD16−HLA-DR−CD33+CD11b+CD14+ M-MDSCs, as shown in figure 1a. Total MDSCs were calculated as the sum of the two subpopulations. Their suppressive character was confirmed via T-cell suppression assay. BAL cell populations were also defined. Further clinical and laboratory data were collected, including diagnosis, stage of disease, findings from microbiological, cytological, and histological examinations, disease course, and end outcomes. The data were analysed with the non-parametric Wilcoxon signed ranks test for paired samples and the Kruskal-Wallis test for comparison between multiple groups.ResultsOur study population included 4 patients with bronchiectasis, 6 patients with lung cancer, and 6 patients with interstitial lung diseases (ILD). MDSCs from all study subgroups showed normal capacity to suppress T cells. All MDSC subsets, including total MDSCs, M-MDSCs, and PMN-MDSCs, were statistically significantly increased in BAL compared to PB, as depicted in figure 1b, indicating the lung accumulation of these cells (p-value: <0.05 in all disease groups). Interestingly, total MDSCs in the BAL were statistically significantly differentiated between the three patient groups, as depicted in figure 1c, with the group of patients with ILD presenting the higher counts (p-value: 0.001).Abstract P251 Figure 1[Image Omitted. See PDF.]ConclusionsOur preliminary data show for the first time that MDSCs could potentially be used as differential diagnostic biomarkers in lung diseases. Additional data are needed to develop disease- and sample-specific reference values of MDSCs and further investigate their quantitative alterations in different entities.

• Publisher: BMJ Publishing Group LTD
• Subject: Biomarkers / Diagnostics / Investigations / Lung diseases