Structural and Functional Characteristics of Autoimmune Pathology in POAG

Abstract

Purpose : Our previous study showed that primary open-angle glaucoma (POAG) patients have elevated autoimmune biomarkers compared to controls. Here we provide the structural and functional characteristics associated with autoimmune pathology.

Methods : In this cross-sectional study, blood samples from 32 patients with POAG were analyzed. Peripheral blood monocytes (PBMC) were stimulated with HSP27, and IFN-γ+ CD4+ T helper type 1 cells (Th1) were identified through flow cytometry. IFN-γ serum levels were determined using enzyme-linked immunosorbent assay. The extent of glaucoma damage was evaluated by right eye total deviation (TD) values for 52 points from Humphrey visual field (VF) tests, and retinal nerve fiber layer thickness (RNFLT) for 12 clock hours via optical coherence tomography. For both HSP27-specific Th1 cells and IFN-γ, age-adjusted tertiles were established. Pearson's correlation (r) was then employed to explore the relationship between autoimmune biomarkers and structural and functional characteristics.

Results : Of the 32 participants, 62.5% were males and 78.1% identified as White. Mean age was 68.8±11.1 years, and mean VF MD was -5.2dB±5.8 dB. The top tertile for IFN-γ showed negative correlations with TD points 23 and 24 representing a superior paracentral defect (p<0.004, Figure 1) while the low tertile showed negative correlation with TD points 52, 53, 54 representing an inferior peripheral visual field defect (p<0.03). Significant positive correlation was found for clock hour 12 in the low HSP27-specific Th1 tertile while no significant correlation was found for any clock hours for any IFN-γ tertiles.

Conclusions : Our results show that patients with high level of IFN-γ tend to have superior paracentral VF loss, while patients without serum level IFN-γ upregulation have inferior peripheral loss. Structurally, patients with low HSP27-specific Th1 counts have superior RNFL preserved. While a larger sample size is needed, these preliminary findings suggest that autoimmune pathology in POAG is associated with specific patterns of VF and RNFL defects.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Association of Autoimmune Biomarkers with VF TD Points and RNFL Clock Hours in POAG.