Reference - Detail
|Author||Kataoka K, Nishiguchi KM, Kaneko H, van Rooijen N, Kachi S, Terasaki H.|
|Title||The roles of vitreal macrophages and circulating leukocytes in retinal neovascularization.|
|Journal||Invest Ophthalmol Vis Sci|
PURPOSE:To analyze the roles of vitreal macrophages and circulating leukocytes in retinal vascular growth.
METHODS:Bone marrow (BM) cells from green fluorescent protein (GFP) transgenic mice were transplanted into postnatal day (P)1 mice after irradiation. The mice were exposed to 76% to 78% oxygen (P7-P12), to initiate oxygen-induced retinopathy (OIR). The eyes were collected at P8, P17, and P30, to analyze the engraftment of GFP-positive cells in the retina. GFP-positive peritoneal macrophages, clodronate liposomes, or control liposomes were injected into the eyes at P5 or P12 to examine the effects at P8 or P17. The number of Iba1-positive vitreal macrophages was quantified from histologic sections at P12 and P17.
RESULTS:Few transplanted GFP-positive cells were found in the retina at P8 in both wild-type and OIR mice. However, their number increased at P17 during retinal neovascularization in OIR. Most GFP-positive cells were Iba1-positive microglia, which comprised a minority of the total retinal microglia. Intravitreal injection of peritoneal macrophages showed only incidental migration of these cells into the wild-type retinas (P8), whereas the engraftment was more robust, typically around the neovascularization, in OIR mice (P17). Furthermore, native macrophages in the vitreous cavity became fewer (37.7% reduction) during neovascularization in OIR at P17. The selective depletion of vitreal macrophages by clodronate liposomes at P12 reduced retinal neovascularization in OIR mice by 59.0% at P17.
CONCLUSIONS:Vitreal macrophages are attracted to the site of pathologic angiogenesis triggered by retinal ischemia, where they actively participate in vascular development.
|MeSH||Animals Bone Marrow Transplantation Calcium-Binding Proteins / metabolism Cell Movement / physiology Clodronic Acid / toxicity Disease Models, Animal* Green Fluorescent Proteins / genetics Intravitreal Injections Leukocytes / physiology* Lymphocyte Depletion Macrophages, Peritoneal / drug effects Macrophages, Peritoneal / physiology* Mice Mice, Inbred C57BL Mice, Transgenic Microfilament Proteins Microglia / metabolism Oxygen / toxicity Phagocytosis / physiology Retinal Neovascularization / metabolism* Retinal Neovascularization / pathology Retinal Vessels / metabolism* Retinal Vessels / pathology Vitreous Body / cytology*|