High dimensional profiling and immune monitoring of Uveitis patients

Abstract

Purpose : Uveitis is a significant cause of severe visual handicap. Evidence links induction of experimental autoimmune uveitis to T cell mediated pathogenesis which is believed to be regulated, at least in part, by natural killer (NK) cells. Here we present the unsupervised multimodal omics of the circulating NK cell compartment in a large cohort of 160 non-infectious uveitis patients (48% with systemic treatement and 52% with no systemic treatement at baseline) and 51 healthy controls.

Methods : Cases and controls were recruited and clinically phenotyped under a prospective clinical study (NCT02656381). We conducted 38-parameter flow cytometry [BD LSR-Fortessa] on freshly collected blood samples, bulk RNA sequencing and single cell RNAseq (scRNAseq) analysis of purified periperhal blood mononuclear cells (PBMCs) [Illumina NovaSeq 6000, 10x Genomics Chromium], and serum targeted proteomics using the Somascan array (SOMAlogic].

Results : Bulk RNA sequencing analysis revealed a clear distinction of PBMCs transcriptome between healthy donors and uveitis patients which was driven by a significant upregulation of NK biology gene (NCAM1, P = 0.012). At the single cell level, scRNAseq analysis could attribute these changes to the enrichment of a distinct subset of NK cells (P < 0.05) characterized by high FCGR3A gene expression in uveitis cases. Flow cytometric analysis confirmed a significant increase of CD16+ NK cells (P = 0.003), and a concomitant decrease of CD56^bright NK subsets (P = 0.002) in the PBMCs of uveitis patients. SOMAlogic analysis revealed a significant decrease (P = 0.028) of NK-inhibitory soluble protein Thrombospondin-1 in the serum of uveitis patients.

Conclusions : The current data are in line with a role for NK cells as an active modulator of autoimmune responses in uveitis patients. A previous study involving blockade of IL2Ra (daclizumab) in uveitis patients showed expansion of CD56^bright NK cells. Our current observation indicates expansion of activated NK cells and decrease in regulatory NK cells in uveitis patients. Further studies are needed to examine the role of NK cells in the development, progression and treatment of uveitis.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.