Abstract
Purpose:
To investigate proinflammatory cytokine levels in the aqueous humor in patients with secondary glaucoma, and to compare those with cataract cases and open-angle glaucoma (OAG) cases.
Methods:
Aqueous humor samples were collected from 70 cataract cases, 110 OAG cases, 14 uveitic glaucoma (UG) cases and 22 neovascular glaucoma (NVG) cases at the beginning of surgery. Anti-vascular endothelial growth factor (VEGF) antibodies were injected into vitreous cavity one or two days prior to the surgery in NVG cases. Aqueous levels of cytokines were determined by multiplex immunoassay. The data were analyzed using the Tukey-Kramer HSD test.
Results:
In the cataract cases, mean (±SD) interleukin (IL)-6, IL-8, monocyte chemotactic protein (MCP)-1, tumor necrosis factor (TNF)-α, platelet-derived growth factor (PDGF)-AA, PDGF-AB/BB, and VEGF levels were 36.2 ± 108.3, 6.1 ± 9.2, 975.1 ± 497.6, 0.9 ± 0.4, 30.0 ± 15.7, 1.2 ± 3.0 and 75.3 ± 34.5 pg/ml, respectively. In OAG cases, the corresponding values were 98.1 ± 568.1, 25.0 ± 41.7, 1502.4 ± 636.1, 0.7 ± 0.6, 45.9 ± 27.9, 3.1 ± 8.4 and 104.3 ± 458.8 pg/ml, respectively. In UG cases, the corresponding values were 44.7 ± 104.4, 86.0 ± 174.2, 1964.6 ± 1107.1, 1.6 ± 1.0, 22,1 ± 4.6, 0.4 ± 1.5 and 55.2 ± 38.9 pg/ml, respectively. In NVG cases, those were 2284.1 ± 3570.0, 329.6 ± 531.8, 3143.7 ± 1209.9, 2.2 ± 0.9, 66.2 ± 43.2, 5.7 ± 9.8 and 137.7 ± 365.7 pg/ml, respectively. In UG cases, the levels of MCP-1 and TNF-α were higher than those in cataract cases (P <0.001 for both cytokines). In NVG cases, the levels of IL-6, IL-8, MCP-1, TNF-α and PDGF-AA were higher than those in cataract cases (P <0.001 for all cytokines). Compared with OAG cases, the levels of TNF-α and PDGF-AA were higher in uveitic cases (P <0.001 and P = 0.007, respectively), and the levels of IL-6, IL-8, MCP-1, TNF-α and PDGF-AA were higher in NVG cases (P <0.001, <0.001, <0.001 and P = 0.005, respectively).
Conclusions:
Patients with secondary glaucoma, especially NVG, showed simultaneous cytokine level increases, suggesting that the aqueous humor microenvironment is altered by the causative ocular diseases of glaucoma.