Low Expression of IL-10 in Circulating Bregs and Inverted IL-10/TNF-α Ratio in Tears of Patients with Perennial Allergic Conjunctivitis: A Preliminary Study

Abstract

Allergic conjunctivitis (AC) is one of the most common ophthalmological disorders seen in clinical practice. Growing evidence from recent years suggests that a subset of IL-10-expressing B cells is involved in inflammatory allergic diseases. In this study, we aimed to evaluate the potential involvement of blood Bregs cells in perennial allergic conjunctivitis (PAC), and interleukins (IL)-1β, IL-6, IL-8, IL-10, and IL-12, and tumor necrosis factor (TNF)-α, were measured in tear samples and compared with healthy controls (HC) using flow cytometry. Non-significant differences in CD19+IL-10+ cell frequency between PAC patients and healthy controls (HC) were observed. Nevertheless, when we analyzed the mean fluorescence intensity (MFI) of IL-10 on CD19+CD38Lo/Med/Hi-gated cells, we observed a significant decrease in MFI in all Bregs subsets in PAC patients. Additionally, tear cytokines showed 2.8 times lower levels of IL-10 than TNF-α in PAC patients when compared to HC. Our findings demonstrate an immunological dysregulation in patients with allergic conjunctivitis, characterized by the low expression of IL-10 in circulating CD19+CD38+ Bregs subsets and an inverted tear IL-10/TNF-α ratio, promoting a local pro-inflammatory microenvironment. These findings highlight the novel pathologic changes involved in ocular allergic diseases. Understanding systemic and local mechanisms will aid the design of immunomodulating therapeutics at different levels.

The correlation between tic disorders and allergic conditions in children: A systematic review and meta-analysis of observational studies

“…TNF-α monoclonal antibody significantly improves nasal symptoms in AR mice ( 20 , p. 517–523). Patients with allergic conjunctivitis demonstrate an immunological dysregulation, characterized by the low expression of IL-10 and an inverted tear IL-10/TNF-α ratio ( 21 ). A systematic review concluded that TNF-α and IL-6 may influence the risk of asthma ( 22 ).…”

Increased Expression of TLR4 in Circulating CD4+T Cells in Patients with Allergic Conjunctivitis and In Vitro Attenuation of Th2 Inflammatory Response by Alpha-MSH

“…The ophthalmological investigation was systematically documented by biomicroscopy, according to [ 39 ]. Schirmer test was performed without instillation of topical anesthetic, folding a Schirmer paper strip (AMCON Tear Flow Test Strips Nomax, Inc, MO, USA) over the temporal one-third of the lower lid margin inserted in the conjunctival sac for 5 min to measure the production of tears in millimeters.…”