Multiplex Bead Analysis of Vitreous Humour in Uveitis and Vitreo-Retinopathies

Abstract

Abstract: : Purpose: We previously presented the results of multiplex bead analysis on aqueous humour from uveitis patients. We have now extended our work to vitreous humour and investigated the role of inflammatory cytokines and chemokines in the pathogenesis of uveitis and various vitreo-retinopathies. Methods: Vitreous samples were obtained from patients with uveitis (n=6), punctate inner choroidopathy (PIC, n=2), proliferative diabetic retinopathy (PDR, n=6), and idiopathic choroidal neovascular membranes (CNVM, n=3). Patients with macular holes were used as controls. Levels of IL-1ß, -2, -4, -5, -6, -8, -10, -12, -13, IFNγ, MCP-1, TNFα, Eotaxin, and RANTES were determined on each sample of vitreous by multiplexed bead analysis using a Luminex100^TM. The concentration of each molecule was determined from a standard curve of known concentrations of recombinant molecules. Results: Initial results showed MCP-1 to be present in all samples, but only elevated in patients with uveitis (range 0-1550 pg/ml, mean 385) and PDR (range 0-2125 pg/ml, mean 867). IL-6 and IL-8 were detected only in the uveitis (IL-6 range 7-2376 pg/ml, mean 439; IL-8 range 0-103 pg/ml, mean 37.3) and PDR (IL-6 range 0-167 pg/ml, mean 39.7; IL-8 range 0-40 pg/ml, mean 19.33) samples. Conclusions: Our results confirm the presence of MCP-1, IL-6 and IL-8 in uveitis vitreous. The finding of MCP-1 in all samples analysed may indicate a role for this molecule in continual recruitment of monocytes involved in immune surveillance. In PDR, elevated MCP-1, IL-6 and IL-8 levels suggest a possible role in pathogenesis. IL-6 and IL-8 were absent in vitreous from PIC and idiopathic CNVM, implying that inflammatory events may not extend to the vitreous in these conditions. We are currently expanding our analysis to a panel of 23 molecules, including angiogenic factors and other chemokines.

Keywords: cytokines/chemokines • vitreous • clinical (human) or epidemiologic studies: sys