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

• Published in: International journal of molecular sciences Vol. 20; no. 5; p. 1035
• Main Authors: Salazar, Alberto, Casanova-Méndez, Israel, Pacheco-Quito, Michele, Velázquez-Soto, Henry, Ayala-Balboa, Julio, Graue-Hernández, Enrique O, Serafín-López, Jeanet, Jiménez-Martínez, María C
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 27-02-2019; MDPI
• Subjects: Allergens; allergic conjunctivitis; Allergies; Animal models; Bregs; CD19 antigen; CD30 antigen; CD38 antigen; Cell surface; Children; Conjunctivitis; Cytokines; Hay fever; Helper cells; IL-10; Inflammation; Interleukin 10; Interleukin 4; Interleukin 5; Lymphocytes B; Lymphocytes T; Phenotypes; Phenotypic variations; tears; TNF-α; Tumor necrosis factor-α; γ-Interferon; allergic conjunctivitis; tears; TNF-α; Bregs; IL-10
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20051035

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⁺CD38
-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.