title: Correlation of cytokine levels and microglial cell infiltration during retinal degeneration in RCS rats.
abstract: Microglial cells, which are immunocompetent cells, are involved in all diseases of the central nervous system. During their activation in various diseases, a variety of soluble factors are released. In the present study, the correlation between cytokine levels and microglial cell migration in the course of retinal degeneration of Royal College of Surgeons (RCS) rats was evaluated. MFG-E8 and CD11b were used to confirm the microglial cells. In the retina of RCS rats, the mRNA expression of seven genes (MFG-E8 and its integrins αυ and ß5, CD11b and the cytokines TNF-α, IL-1ß, and MCP-1) formed almost similar bimodal peak distributions, which were centred at P7 and P45 to P60. In contrast, in rdy rats, which comprised the control group, a unimodal peak distribution centred at P14 was observed. The gene expression accompanied the activation and migration of microglial cells from the inner to the outer layer of the retina during the process of degeneration. Principal component analysis and discriminant function analysis revealed that the expression of these seven genes, especially TNF-α and CD11b, positively correlated with retinal degeneration and microglial activity during retinal degeneration in RCS rats, but not in the control rats. Furthermore, linear regression analysis demonstrated a significant correlation between the expression of these genes and the activation of microglial cells in the dystrophic retina. Our findings suggest that the suppression of microglial cells and the blockade of their cytotoxic effects may constitute a novel therapeutic strategy for treating photoreceptor death in various retinal disorders.
authors.affiliation: Southwest Hospital, Southwest Eye Hospital, Key Laboratory of Visual Damage and Repair of Chongqing, Third Military Medical University, Chongqing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Tropical Medicine, Third Military Medical University, Chongqing, China.
authors.forename: Xuesen
authors.initials: X
authors.lastname: Yang
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America ; Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway.
authors.forename: Tor Paaaske
authors.initials: TP
authors.lastname: Utheim
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Chenying
authors.initials: C
authors.lastname: Guo
authors.affiliation: College of Life Sciences, Southwest University, Chongqing, China.
authors.forename: Mingchun
authors.initials: M
authors.lastname: Xiao
authors.affiliation: Institute of Tropical Medicine, Third Military Medical University, Chongqing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Southwest Hospital, Southwest Eye Hospital, Key Laboratory of Visual Damage and Repair of Chongqing, Third Military Medical University, Chongqing, China.
authors.forename: Zhengqin
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000235:genetics / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics; D048430:Cell Shape / Q000235:genetics; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D007249:Inflammation / Q000235:genetics / Q000473:pathology; D016023:Integrins / Q000235:genetics / Q000378:metabolism; D008297:Male; D017628:Microglia / Q000378:metabolism* / Q000473:pathology*; D008894:Milk Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D012160:Retina / Q000378:metabolism / Q000473:pathology; D012162:Retinal Degeneration / Q000378:metabolism* / Q000473:pathology*; D012165:Retinal Ganglion Cells / Q000378:metabolism / Q000473:pathology
chemical_list: D000954:Antigens, Surface; D016207:Cytokines; D016023:Integrins; C499941:MFGE8 protein, rat; D008894:Milk Proteins; D012333:RNA, Messenger