Innate immune responsive inflammation in development of progressive myopia.

PURPOSE: Inflammation has been implicated for development of myopia. It is not clear when inflammation is kicked in during the course of myopia, and what characteristics of the inflammation. In this study, we tested for cytokines from aqueous humour of eyes with wide spectrum of refractive status for profiling the inflammation. METHODS: Aqueous humour of 142 patient eyes were tested for soluble intercellular adhesion molecule 1 (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), and transforming growth factor-beta 2 (TGF-ß2) using an enzyme-linked immunosorbent assay (ELISA). Eye globe axial length of these patients ranged from emmetropia to high myopia. RESULTS: Of 142 patients, an average axial length is 25.51 ± 3.31 mm, with a range of 21.56-34.37 mm. There are 36 cases in lower 25 percentile, 37 cases in upper 25 percentile, and 69 case in the middle 50 percentile. sICAM-1 and MCP-1 were significantly higher in the eyes with staphyloma (407.48 pg/mL, 312.31 pg/mL, n = 33) or macular schisis (445.86 pg/mL,345.33 pg/mL, n = 19) than that in the eyes without these changes (206.44 pg/mL, 244.76 pg/mL, n = 107). All three cytokines level was significantly associated with eye globe axial in a positive mode while adjusting for the age and sex. Strength of the association was the greatest for sICAM-1 and the weakest for TGF- ß2. MCP-1 was in between. CONCLUSION: sICAM-1 and MCP-1 in ocular fluid may be indicative biomarkers for progressive high myopia and the underneath autoimmune inflammation. sICAM-1 may be used as a monitoring biomarker for development of pathologic myopia.

Inflammatory cytokines in highly myopic eyes.

Currently, myopic retinopathy is the most common irreversible blinding disease but its pathophysiology is not completely clear. A cross-sectional, observational study was conducted in a single center to analyze aqueous samples from highly myopic eyes (axial length >25 mm, n = 92) and ametropic or mild myopic eyes (n = 88) for inflammatory cytokines. Vascular endothelial growth factor (VEGF), Interleukin 6 (IL-6), and matrix metalloproteinase-2 (MMP-2) were measured using an enzyme-linked immunosorbent assay. IL-6 and MMP-2 were significantly higher in the highly myopic eyes than in the non-high myopic eyes (IL-6: 11.90 vs. 4.38 pg/mL, p < 0.0001; MMP-2: 13.10 vs. 8.82 ng/mL, p = 0.0003) while adjusting for age, gender, and intraocular pressure. There was a significant positive association between levels of IL-6 and MMP-2 in aqueous humor and the axial lengths of the eye globes (IL-6, ß = 0.065, p < 0.0001, n = 134; MMP-2, ß = 0.097, p < 0.0001, n = 131). Conversely, VEGF in aqueous humor was significantly lower in the highly myopic eyes than in the non-high myopic eyes (45.56 vs. 96.90 pg/mL, p < 0.0001, n = 153) while age, gender, and intraocular pressure were adjusted. The results suggest that low-grade intraocular inflammation may play an important role in the development and progression of high myopia and myopic retinopathy.