Proteome analysis of retinal glia cells-related inflammatory cytokines in the aqueous humour of diabetic patients.
OBJECTIVE
Retinal glia cells (RGC) activation and release of inflammatory cytokines have been associated with development of diabetic retinopathy (DR). In this study, we evaluated by protein array the presence of aqueous humour (AH) cytokines secreted by RGC in patients with diabetes without DR and with mild DR.


METHODS
This is a cross-sectional, case-control study. Thirty-five subjects (diabetics and controls) underwent full ophthalmic examination and AH samples collection before cataract surgery at the Department of Ophthalmology University of Padova. AH samples were analysed for total protein concentration (Bradford method) and RGC-related inflammatory cytokines using glass chip protein arrays.


RESULTS
Twelve diabetic patients without DR, 11 diabetic patients with mild DR and 12 non-diabetic controls were included. There was no significant difference in total protein concentration among the 3 groups. Interleukin IL-1β, IL-3, interferon gamma (IFN-ɣ), (IFN-ɣ)-induced protein (IP)-10 and monocyte chemotactic protein (MCP)-2 were significantly increased in diabetics versus controls. IFN-ɣ, IL-1α, IL-3 and MCP-2 were significantly increased in diabetics without DR versus controls, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF), IFN-ɣ, IL-10, IP-10, regulated and normal T cell expressed and secreted (RANTES), and soluble tumour necrosis factor receptor (sTNF-R)II were significantly increased in diabetics with mild DR versus controls. Macrophage inflammatory protein (MIP-1β), GMCSF, RANTES and sTNF-RII were significantly increased in diabetics with mild DR versus diabetics without DR (p < 0.05 at least for all).


CONCLUSIONS
Differences in expression profile of AH cytokines between diabetics, without and with mild DR, and controls have been documented. Retinal neuroinflammatory biomarkers of RGC activation evaluated in AH by protein array analysis could guide in detecting specific phenotypes with potential for personalized management.
Department of Ophthalmology, University of Padova, Padova, Italy.
Stela
S
Vujosevic
Fondazione G. B. Bietti, IRCCS, Roma, Italy.
Alessandra
A
Micera
Department of Ophthalmology, University of Padova, Padova, Italy.
Silvia
S
Bini
Department of Ophthalmology, University of Padova, Padova, Italy.
Marianna
M
Berton
Fondazione G. B. Bietti, IRCCS, Roma, Italy.
Graziana
http://orcid.org/0000-0002-8777-197X
G
Esposito
Department of Ophthalmology, University of Padova, Padova, Italy.|Fondazione G. B. Bietti, IRCCS, Roma, Italy.
Edoardo
E
Midena
D000368:Aged; D001082:Aqueous Humor / Q000378:metabolism*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009457:Neuroglia / Q000378:metabolism*; D011446:Prospective Studies; D040081:Protein Array Analysis; D020543:Proteome / Q000378:metabolism*; D055351:Retinal Neurons / Q000378:metabolism*
D016207:Cytokines; D020543:Proteome
Muller cells; aqueous humour; diabetic retinopathy; inflammation; microglia; proteomic; retinal glia cells