title: Scavenger receptors for oxidized lipoprotein in age-related macular degeneration.
abstract: OBJECTIVE
  The accumulation of macrophages is known to be involved in the pathogenesis of age-related macular degeneration (AMD), but the reasons why macrophages accumulate in AMD lesions have not been determined. Because the histopathology of AMD has some factors common with those of atherosclerosis, the authors hypothesized that macrophages accumulate to take up oxidized lipoproteins in the eyes of patients with AMD, as has been demonstrated in atherosclerosis.
  
  
  METHODS
  Immunohistochemistry was performed on 10 surgically excised choroidal neovascular (CNV) membranes from eyes with AMD. An antibody against oxidized lipoprotein and antibodies against the scavenger receptors SR-PSOX and LOX-1 were used. Antibodies against cytokeratin, CD68, and von Willebrand factor were used to identify retinal pigment epithelium (RPE), macrophages, and vascular endothelial cells, respectively. RT-PCR was performed to detect the mRNAs of the scavenger receptors in the CNV membranes.
  
  
  RESULTS
  Oxidized lipoproteins were immunohistochemically detected in the CNV membranes. Intense immunostaining was observed at the surface of the CNV membranes with the SR-PSOX antibody, whereas LOX-1 immunostaining was weak. Cells expressing scavenger receptors were found to be predominantly macrophages with a minority of RPE. Both SR-PSOX and LOX-1 mRNAs were detected in CNV membranes.
  
  
  CONCLUSIONS
  Oxidized lipoproteins are present in AMD lesions. Macrophages and RPE in the CNV membranes express cell surface scavenger receptors for oxidized lipoproteins. These findings suggest that macrophages may accumulate to take up oxidized lipoproteins in AMD and that the control of oxidative stress and macrophage responses may therefore be potential treatments for AMD.
authors: Department of Ophthalmology, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan. mkamei@ophthal.med.osaka-u.ac.jp
authors: Motohiro
authors: M
authors: Kamei
authors: Kazuhito
authors: K
authors: Yoneda
authors: Noriaki
authors: N
authors: Kume
authors: Mihoko
authors: M
authors: Suzuki
authors: Hiroyuki
authors: H
authors: Itabe
authors: Ken-Ichi
authors: K
authors: Matsuda
authors: Takeshi
authors: T
authors: Shimaoka
authors: Manabu
authors: M
authors: Minami
authors: Shin
authors: S
authors: Yonehara
authors: Toru
authors: T
authors: Kita
authors: Shigeru
authors: S
authors: Kinoshita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D000075743:Chemokine CXCL16; D019743:Chemokines, CXC / Q000235:genetics / Q000378:metabolism*; D020256:Choroidal Neovascularization / Q000378:metabolism / Q000601:surgery; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007633:Keratins; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism; D008268:Macular Degeneration / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051116:Receptors, Scavenger / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051127:Scavenger Receptors, Class E / Q000235:genetics / Q000378:metabolism*; D014841:von Willebrand Factor; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D000075743:Chemokine CXCL16; D019743:Chemokines, CXC; D007633:Keratins; D008077:Lipoproteins, LDL; D012333:RNA, Messenger; D051116:Receptors, Scavenger; D051127:Scavenger Receptors, Class E; D014841:von Willebrand Factor; C067980:CD68 antigen, human; D000097382:CD68 Molecule; C423727:CXCL16 protein, human; C495137:OLR1 protein, human; C099252:oxidized low density lipoprotein