Purpose:
To investigate the morphological and functional changes of microglia/macrophage in the retina of rat model of glaucoma immunized by Cop-1 and speculate the potential effect of activated microglia.
Methods:
Randomized controlled trials.96 female Wistar rats,of each glaucoma model established,were divided into 2 groups randomly.There are 48 rats with elevated IOP immunized by Cop-1(Cop-1 group), 48 rats with elevated IOP immunized by PBS (PBS group).Activation and distribution of microglia/ macrophages were observed by immunohistochemisty and Western-blot was used to measure the MHC-II expression on microglia/macrophages in the retina.Co-culturing of Cop-1-specific Tcells and microglia to evaluate the activation of microglia and determine its relationship with Cop-1 specific T cells.Supernatant of co-cultured medium was collected on the 12h, 24h and 48h,then BDNF, IL-10 and TNF-α Elisa kits were used to explore the probable function of activated microglia.All data collected were compared among groups using T test and multiple comparisons test.
Results:
The number of microglia/macrophages in the retina increased in the experimental eyes.The amount of microglia/macrophages in Cop-1 group was higher than PBS group on the 7th and 10th day (P<0.001).The results of Western-blot also showed the activation of microglia in Cop-1 group.Co-culturing of Cop-1 specific T cells and microglia in vitro proved that microglia were activated with morphological and functional changes while culturing of microglia alone with Cop-1 didn’t show significant activation.The secretion of BDNF, TNF-α in Cop-1 specific T cell-microglia supernatant were higher than normal T cell-microglia group.Secretion of TNF-α was the highest in the co-cultured group on the 12h and BDNF,IL-10 reached the highest on 48h.
Conclusions:
Microglia/macrophages were activated in the retina of the rat model of glaucoma immunized by Cop-1 and this procedure is Cop-1 specific T cells mediated.The interaction between Cop-1 specific T cells and microglia made the secretion of some cytokines change,suggesting the underlying neuroprotective reaction and immune regulation.
Keywords: microglia • neuroprotection • protective mechanisms