MicroRNA Profiling in Extracellular Vesicles from Vitreous Humor and Serum of Patients with Ocular Sarcoidosis and Vitreoretinal Lymphoma

Abstract

Purpose : To investigate the microRNA (miRNA) profiles in extracellular vesicles (EVs) isolated from vitreous and serum of patients with ocular sarcoidosis and vitreoretinal lymphoma (VRL).

Methods : This study analyzed vitreous and serum samples from two cohorts: an exploratory cohort comprising three patients each diagnosed with ocular sarcoidosis, vitreoretinal lymphoma, and controls (vitreous from patients with macular hole or preretinal membrane, serum from patients with cataract), and a validation cohort consisting of 16 patients from each group. EVs in vitreous and serum were isolated using ultracentrifugation method, and the collected particles were confirmed using nanoparticle tracking analysis and Western blotting. Subsequently, miRNAs were extracted from the EVs and subjected to comprehensive miRNA sequencing to compare the miRNA expression profiles among the groups in the exploratory cohort. Next, we performed a comparative analysis using quantitative PCR (qPCR) on several miRNAs that demonstrated significant differences in the exploratory cohort, evaluating their expression in the validation cohort.

Results : Nanoparticles approximately 100 nm in size expressing CD9 and CD63 were detected in the vitreous and serum of all groups. In the miRNA sequencing analysis, a total of 2,697 miRNAs were extracted from vitreous EVs, and 2,713 miRNAs from serum EVs across all groups. Compared to the control group, ocular sarcoidosis showed significant changes in expression level in 25 miRNAs in the vitreous and 36 miRNAs in serum, while VRL exhibited significant expression changes in 52 miRNAs in the vitreous and 77 miRNAs in serum. In addition, the results of qPCR conducted in the validation cohort revealed that in VRL, miR-15a-3p and miR-8069 were significantly upregulated in the vitreous. In contrast, in ocular sarcoidosis, let-7i-5p and miR-21-5p were significantly upregulated, while miR-517-5p was significantly downregulated.

Conclusions : This study revealed the miRNA profiles in EVs isolated from the vitreous and serum of patients with ocular sarcoidosis and VRL. Our findings suggest that the observed differences in these miRNA profiles may be associated with the development of ocular sarcoidosis and VRL. These results may provide valuable insight into the pathogenesis of these conditions and contribute to the development of novel biomarkers.

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