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Background: Vernal keratoconjunctivitis (VKC) is a chronic, potentially blinding ocular allergic disease affecting children with uncertain pathogenic mechanisms., Objective: To identify differences in gene expression between VKC and normal subjects (CT) and to evaluate the expression of pattern recognition receptors (PRRs)., Methods: Conjunctival cells were collected by impression cytology device from 25 VKC patients and 10 CT. Isolated RNA was assayed with the NanoString human immunology codeset to evaluate the expression levels of immunology-related genes., Results: Of the 579 genes, 398 were detected and 58 were significantly differently expressed in VKC compared to CT. The number of significantly differentially expressed genes (DEG) in the 3 different phenotypes vs CT were 149 in tarsal, 17 in limbal and 68 in the mixed form of VKC. The list of the most overexpressed genes included several chemokines (CCL24, CCL18, CCL22, CXCL1), proinflammatory cytokines (IL-1β, IL-6, IL-8, TGFβ-1) and genes related to Th2- and Th17-signaling families. Toll like receptors (TLR)4 and TLR8, Dectin-1/CLEC7A, mincle/CLEC4E, MCR1, NOD2 and NLRP3 and several of their pathway-related genes were significantly overexpressed in VKC. The number of DEG increased with the disease severity either in IgE+ or IgE- patients. Immunohistochemistry analysis of VKC conjunctival tissues confirmed an increased expression of these molecules at protein level., Conclusions: The increased expression of several chemotactic factors and co-stimulatory signals required for T-cell activation, confirms that VKC is mostly cell-mediated with local eosinophilia. The multiple expression of PRRs suggests a role of host-pathogens interaction in VKC development., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: The aim of this study was to characterize the expression of inflammation-related genes on the ocular surface of Sjögren syndrome (SS) patients and to evaluate their correlations with clinical symptoms and signs., Methods: The study enrolled 30 patients with SS dry eye and 15 healthy controls. Symptoms were evaluated using OSDI questionnaire. The clinical signs were investigated using corneal fluorescein staining (CFS), tear breakup time (TBUT), Schirmer test and tear osmolarity measurement. Conjunctival superficial cells were collected using conjunctival impression cytology and total RNAs were extracted for analysis using the NanoString ® nCounter technology. The Mann-Whitney nonparametric statistical test and Spearman correlations were used to explore the correlations between the up/downregulated genes and the clinical signs and symptoms., Results: Twenty-seven genes were upregulated and 13 were downregulated with statistically significant fold changes ranging from 1.5 to 16.7 and 0.3 to 0.8, respectively. OSDI and CFS were the most significantly correlated parameters with 21 and 19 inflammatory genes, respectively. Among all the upregulated genes, 14 were positively correlated with both OSDI and CFS. Two downregulated genes (GNGT1, HSPB2) were negatively correlated with OSDI and CFS. IL1RN was the only gene positively correlated with the Schirmer test., Conclusions: These results highlight the differentially expressed genes in primary Sjögren syndrome and their relationships between the inflammatory genes expressed and the patient symptom score and corneal damage. The inflammatory genes implicated in SS-associated dry eye could be important tools to determine the pathophysiological profiles of SS and potentially useable as specific signatures., (Copyright © 2019. Published by Elsevier Inc.)