Peripheral Blood B-Cell Subsets Frequency and Distribution and the BSF-2(IL-6) to CSIF:TGIF(IL-10) Ratio as Severity-Associated Signatures in Primary Open-Angle Glaucoma: A Case-Controlled Study

Abstract

Although primary open-angle glaucoma (POAG) is a major cause of blindness worldwide, patients’ immune response and its relation to the disease course have not been fully unraveled in terms of analyses of circulating B-cell subsets, as well as the association of these subsets with the severity of POAG clinical features. Subjects and Methods: Flow cytometry was used to determine B-cell subset frequencies from 30 POAG patients grouped by hierarchical cluster analysis or the mean deviation (MD) of the visual field (VF) and correlated with the patients’ clinical and pathological data, as well as with BSF-2(IL-6) and CSIF:TGIF(IL-10), which were quantified in peripheral blood samples of patients and controls by ELISA. Results: The total B-cell frequency was increased in the POAG group in comparison to the control group (n = 30). Frequencies of specific B-cell subsets, such as double-negative (DN) and naïve B-cell subsets, were increased in relation to the severity of the POAG disease. However, the unswitched memory B compartment subset decreased in the POAG group. Other non-typical B-cell subsets such as DN B cells also showed significant changes according to the POAG disease severity course. These differences allow us to identify POAG severity-associated inflammatory clusters in patients with specifically altered B-cell subsets. Finally, ocular parameters, biomarkers of inflammation, and other glaucoma-related or non-clinical scores exhibited correlations with some of these B-cell subpopulations. Conclusion: The severity of the POAG disease course is accompanied by changes in the B-cell subpopulation, namely, DN B cells. Furthermore, the existing relationship of the B-cell subset frequencies with the clinical and the inflammatory parameters BSF-2(IL-6), CSIF:TGIF(IL-10), and the BSF-2(IL-6) to CSIF:TGIF(IL-10) ratio suggests that these B lymphocyte cells could serve as potential molecular bio-markers for assessing POAG disease severity and/or progression.