Expression and significance of toll-like receptors in peripheral blood mononuclear cells of patients with wet age-related macular degeneration

Abstract:

Objective：To investigate whether the toll-like receptors（TLRs） 3/4 are associated with wet form age-related macular de－generation（AMD）. Methods：Blood samples were collected from 25 wet AMD patients and 24 age-matched healthy controls. Peripher－al blood mononuclear cells（PBMCs） were isolated by Ficoll-Hypaque density gradient centrifugation. Expression of TLR3 and TLR4 mRNA was assessed by real-time PCR. TLR3 protein level was measured with flow cytometry. After stimulating PBMCs with specific ligands PolyI∶C，cytokines IL-6，IL-8 and MCP-1 protein productions were assessed. Results：TLR3 mRNA and protein expression was significantly higher in the PBMCs of wet AMD patients than those in controls. However，the differences of TLR4 mRNA expression between the two groups were not significant. The PBMCs of wet AMD patients produced more IL-6 protein than the controls in response to PolyI∶C，the ligand for TLR3. But there was no significant difference in MCP-1 production between wet AMD group and control group when stimulating PBMCs with PolyI∶C. Conclusion：Our data suggest that upregulation of TLR3 signal pathways maybe a critical link in the pathogenesis of wet AMD.