B and T lymphocytes interactions via VISTA-PSGL1 is associated with tumor recurrence in early-stage NSCLC.

Purpose: Among the diverse array of immune cells populating the tumor microenvironment, B cells have emerged as key orchestrators of immune responses. Despite their evident involvement, there is a lack of data regarding the characterization of B cell phenotypes, bioenergetic profiles, and potential interactions with T cells within the context of resectable non-small cell lung (rNSCLC). Methods: Thirty-seven individuals with rNSCLC were enrolled in the study, and the phenotype of tumor-infiltrating B and T cells was analyzed using two flow cytometry panels (18 and 21 markers for B and T cells, respectively). Special attention was paid to recently discovered immune checkpoints such as CD226, CD96, PSGL1, and VISTA. A 45-parameter mass cytometry panel was employed to obtain the metabolic profile of these cells (single-cell metabolic regulome profiling, scMEP by CyTOF). NicheNet and NSCLC spatial transcriptomics datasets (CosMX, Nanostring) were utilized to map the ligand-receptor interactions and their effects on interacting cells. Intracellular cytokine staining (ICS) was employed to measure cellular responses after in vitro stimulation with PMA/ionomycin. Prediction of cancer relapse was performed using PENCIL. Results: The examination of memory T cells revealed that both CD4+ and CD8+ subsets express PSGL1 and exhibit metabolic profiles varying from heightened metabolic activation to limited glycolytic capacity alongside an intensified effector profile. Conversely, B cells exhibited an increased presence of a specific type of B regulatory (Bregs) cell expressing VISTA and IL-10 within tumor environments. These cells displayed augmented metabolic activity across various pathways including amino acid metabolism, glycolysis, pentose phosphate pathway, fatty acid oxidation, and the tricarboxylic acid cycle, coupled with elevated production of GM-CSF, TNF, IL-6, IL-10, IFN-γ, and TGF-β. Computational modeling of T and B cell interactions identified VISTA-PSGL1 as a likely ligand-receptor pair in rNSCLC specimens. Spatial analysis of rNSCLC data revealed close proximity between T and B cells within tertiary lymphoid structures. Predictive analysis indicated that the presence of high infiltrate of VISTA+ Bregs and PSGL1+ CD8+ T might be associated with lung cancer recurrence. Conclusion: Our results indicate a possible interaction between Bregs and T cells via the VISTAPSGL1 axis, capable of impacting the recurrence of NSCLC.