Analysis of Th17-associated cytokines in tears of patients with dry eye syndrome

Abstract

Purpose To determine the levels of Th17-associated cytokines, particularly interleukin (IL)-17 and IL-22 in tears of patients with dry eye syndrome. Methods Tear samples were collected from 20 healthy volunteers, 20 dry eye (DE) patients with non-Sjö gren's syndrome (NSSDE) and 20 DE patients with Sjö gren's syndrome (SSDE). Symptom questionnaire was self-administered and multiple dry eye disease (DED)-related clinical tests were performed. The levels of IL-17 and IL-22 in tears were measured by enzyme-linked immunosorbent assay. Results The levels of IL-17 and IL-22 were significantly increased in tears of DE patients compared with those of controls and also higher in SSDE patients compared with those of NSSDE patients (Po0.05). Moreover, the levels of IL-17 and IL-22 were positively correlated with questionnaire score and keratopathy score but negatively correlated with tear film break-up time and Schirmer I test in both NSSDE and SSDE patients (Po0.05). Conclusions The levels of IL-17 and IL-22 in tears were significantly increased in DE patients, which were associated with the disease severity. Therefore, Th17 cellassociated cytokines, particularly IL-17 and IL-22, may have important roles in the immunopathogenesis of the DED.

Analysis of Th17-associated cytokines and clinical correlations in patients with dry eye disease

“…Findings of Yoon et al[10] and Lam et al[17]showed that the level of IL-17 in tears from DED patients was increased. The correlation studies revealed associations between some of inflammatory mediators such as IL-6, IL-17 and IL-22 and ocular surface parameters[12, 13, 17]. However, few study specifically focused on Th17-associated cytokines and limited data have been published evaluating the expressions of cytokines in mRNA levels.…”

“…It is now recognized that CD4 + T cells including T helper 1 (Th1) cells and T helper 17 (Th17) cells are thought to be the effector T cells and moreover, Th17 cells are primarily responsible for maintaining the chronic and relapsing course of the disease[7, 8]. Several studies have shown that increased levels of inflammatory cytokines such as interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor (TNF)-α found in tears[9–12], and Tan et al showed that IL-17 and IL-22, the effective cytokines of Th17 cells, significantly increased in tears of patients with DED[13]. Thus, inflammatory cytokines particularly Th17-associated cytokines may play roles in the pathogenesis of the disease.…”

Unmasking the pathogenic role of IL-17 axis in primary Sjögren's syndrome: A new era for therapeutic targeting?

“…Due to ethical and technical problems in histological studies of human lacrimal glands, tears represent a powerful tool to investigate pSS-dry eye. Although lacrimal IL-17 is increased in dry eye syndrome of different etiology in humans and animal models [75][76][77] such increase is significantly more pronounced in pSS patients compared to those with non-pSS dry eye syndrome. In addition, a parallel elevation of IL-6 has been also observed in pSS tears, suggesting an underlying loop to maintain Th17 response in lacrimal glands [76].…”

Meibomian Gland Disease

“…2,69 A study examining the inflammatory cytokines IL-17 and IL-22 found that they were increased in patients with dry eye and positively correlated with dry eye questionnaire and keratopathy scores. 70 …”