Aqueous humor cytokine levels through microarray analysis and a sub-analysis based on optical coherence tomography in wet age-related macular degeneration patients

Abstract

Background: To identify disease-specific cytokine and growth factor profile differences in the aqueous humor between wet age-related macular degeneration (AMD) patients and age-matched controls and to correlate their levels with the optical coherence tomography (OCT) findings. Methods: Aqueous humors were obtained from 13 wet AMD eyes and 10 control eyes. Twenty cytokines and growth factors were measured using a RayBio antibody microarray technology in wet AMD and control eyes. Results: The samples obtained from wet AMD patients exhibited a significantly increased expression of MCP-1, MIP-1α, MIP-1β, and vascular endothelial growth factor (VEGF). Subretinal fluid (SRF) patients showed significantly lower levels of proinflammatory cytokines, such as IL-1α and GM-CSF, than those without SRF. Pigment epithelial detachments (PED) patients showed lower levels of inflammatory cytokines, such as GM-CSF, IFN-γ, and TNF-α, than those without PED. Subretinal tissue (SRT) patients showed a higher level of IFN-γ than those without SRT. Compared with the controls, type 1 macular neovascularization (MNV) patients showed increased levels of MCP-1, MIP-1α, and MIP-1β, but not VEGF (p = 0.083). However, type 2 MNV patients showed increased levels of MCP-1 and VEGF (p = 0.040 and p = 0.040). Conclusion: Inflammatory cytokines varied according to the type of AMD- and OCT-based parameters. Our observation of low levels of VEGF in patients with type 1 MNV implies that the inhibition of VEGF alone appears to be insufficient treatment for these patients and that cytokines such as MCP-1, MIP-1α, and MIP-1β should be modulated. And the presence of SRF in MNV may be associated with a positive prognosis because we found relatively low levels of proinflammatory cytokines.