光动力学疗法治疗角膜新生血管后角膜的光电镜改变

目的观察应用国产光敏剂行光动力学疗法(PDT)治疗角膜新生血管后角膜的组织学改变。方法碱烧伤有色兔角膜制作角膜新生血管模型。血啉单醚5mg/kg自耳缘静脉注射,不同的能量密度61.2-52.8J/cm2的氲绿激光照射角膜新生血管根部,不注射血啉单醚并单纯行同等能量密度的激光照射组作为对照组,PDT治疗后3h、1周、1个月行角膜光电镜检查。结果PDT后3h可见角膜急性炎症反应,有大量中性粒细胞浸润和少量嗜酸性白细胞浸润,虹膜组织无损伤。PDT后1周角膜炎症反应大部分消失,可见新生血管腔内有无定形物质填塞和许多影子血管。透射电镜显示:PDT组角膜新生血管内皮细胞内线粒体显示出空泡样变,细胞形态不完整。结论血啉单醚作为光敏剂,应用氩绿激光对角膜新生血管行PDT治疗,导致新生血管内皮细胞损伤,能有效封闭角膜新生血管,对周围组织无明显损伤。     

培养角膜缘干细胞羊膜移植治疗碱烧伤动物的实验研究

目的 观察培养生长于羊膜的角膜缘干细胞移植的治疗角膜缘碱烧伤伤的效果。方法 将兔角膜缘干细胞在的代培养后接种于羊膜,对新西兰大白兔角膜缘碱烧伤动物模型行角膜缘干细胞羊膜移植术,并对治疗后的角膜进行临床及病理学检查。结果 体外培养的兔角膜缘士细胞可在羊膜上继续增殖、分化为密集的角膜上皮细胞层;角膜缘干细胞移植术后兔角膜缘轻度充血、角膜上皮完整基质细胞浸润减轻、新生血管减少。组织病理学染色证实,角膜缘     

培养角膜干细胞羊膜片移植治疗角膜缘功能障碍

目的：临床观察培养的角膜干细胞羊膜移植片治疗角膜缘功能障碍的效果。方法：人角膜缘干细胞原代培养后接种生长于羊膜上,临床选择角膜缘烧伤后（碱烧伤、酸烧伤、其他化学烧伤等）,角膜新生血管的患者进行干细胞羊膜片移植,术后观察角膜上皮、组织浸润和新生血管情况。结果：术后患者自觉症状轻,视力有一定提高,角膜缘移植片紧密贴附,角膜上皮完整,轻度基质炎性浸润,浅层新生血管减少,深层新生血管充盈减轻,睑球粘连得到     

早期自体角膜缘移植术治疗碱烧伤

目的探讨角膜缘移植术在眼碱烧伤中的治疗意义。方法新西兰兔１４只，１．０ｍｏｌ／ＬＮａＯＨ溶液眼前节烧伤１分钟。其中７只兔于烧伤后即实施自体角膜缘移植术，另７只兔为对照。术后观察１个月，取其角膜进行光镜及扫描电镜观察。结果手术组角膜上皮愈合快，角膜新生血管及角膜炎细胞浸润均较对照组轻。结论早期自体角膜缘移植术治疗碱烧伤可加速角膜上皮愈合、抑制角膜新生血管形成、减轻角膜炎症反应及预防角膜溃疡的发生。     

大鼠角膜新生血管模型中基质金属蛋白酶-2及其抑制物的表达

目的 探讨大鼠角膜碱烧伤后基质金属蛋白酶－2（MMP－2）及其组织型抑制剂（TIMP－2）在角膜中的表达和意义。方法 采用碱烧伤大鼠角膜建立角膜新生血管动物模型；应用免疫组织化学技术检测MMP－2及TIMP－2在角膜新生血管模型不同阶段的表达和变化。结果 实验鼠于伤后3－天开始形成大量新生血管，可见炎性细胞浸润，伤后14－21天新生血管和炎性细胞均明显减少。免疫组化显示MMP－2于伤后1天表达开始升高，3天达最高，以后逐渐下降。而TIMP－2则于早期变化不明显，7天表达开始升高，14天达高峰。结论 大鼠角膜新生血管形成早期MMP－2活性增高，继而TIMP－2分泌增多，MMP－2活性受抑，基底膜降解受阻，新生血管延伸停滞。     

大鼠角膜缘上皮细胞培养与同体移植的实验研究

目的：观察以明胶为载体培养的角膜缘上皮细胞移植治疗角膜缘干细胞缺乏症的疗效。 方法：大鼠角膜缘上皮细胞在铺有明胶载体的细胞培养板上进行培养5d后,角膜上皮细胞移植术前24h用3H胸腺嘧啶核苷标记培养的角膜缘上皮细胞,培养标记的角膜缘上皮细胞对角膜缘干细胞缺乏的大鼠动物模型行角膜缘上皮细胞同体移植术,对移植术后角膜进行观察、病理学检查及同位素检测。 结果：大鼠角膜缘上皮细胞可以在明胶载体上培养、增殖、分化为密集角膜上皮细胞层;角膜缘上皮细胞移植术后角膜上皮完整、基质细胞浸润减轻、新生血管减少。病理学检查角膜缘及周边部上皮细胞为多层结构,角膜新生血管消失及基质中炎性细胞浸润减轻。角膜缘上皮细胞移植术后4wk受眼角膜仍可测到3H胸腺嘧啶核苷。 结论：角膜缘上皮细胞移植治疗角膜缘干细胞缺乏症可恢复角膜缘干细胞缺乏病变角膜上皮结构的完整性,减少角膜新生血管的形成,维持角膜缘干细胞的屏障功能,为角膜移值提供更好的条件。     

培养兔自体角膜缘干细胞移植的实验研究

目的 观察以羊膜为载体的兔角膜缘于细胞膜片移植治疗兔角膜缘于细胞缺损的效果。方法 制造兔角膜缘干细胞缺损的动物模型,以右眼为实验眼,从兔左眼取角膜缘组织,将兔角膜缘干细胞消化下来,接种于铺有羊膜的无菌六孔培养板中,待细胞形成多层角膜上皮细胞后,对兔角膜缘干细胞缺损动物模型行角膜缘干细胞羊膜移植术,并对治疗后的角膜进行裂隙灯及病理学检查。结果 临床和组织病理学染色证实：体外培养的兔角膜缘干细胞可在羊膜上继续增生、分化为多层角膜上皮细胞;角膜缘干细胞移植术后兔角膜缘轻度充血、角膜上皮完整、基质细胞浸润减轻、新生血管减少或消失。结论 应用角膜缘干细胞羊膜移植术可恢复其角膜上皮结构的完整性,减少角膜新生血管的形成,维持角膜缘的细胞屏障功能。     

角膜碱烧伤白细胞介素-1ra基因治疗的实验研究

目的探讨阳离子聚合物包装IL-1ra重组质粒、角膜原位转染治疗角膜碱烧伤的疗效。设计实验性研究。研究对象角膜碱烧伤大鼠动物模型。方法制作Wistar大鼠角膜碱烧伤模型，随机分为2组，Ⅰ组为阴性对照（12只），结膜下注射生理盐水。Ⅱ组为IL-1ra基因治疗组（18只），以PeDNA3．1质粒作为IL-1ra基因表达载体，阳离子聚合物为转染介质，角膜基质显微注射20μg IL-1ra质粒。碱烧伤后不同时间点（3、7、21天）处死实验动物取下角膜，HE染色分析角膜组织病理变化，比较两组角膜透明性和新生血管生长情况，对角膜内浸润的炎性细胞进行计数。主要指标角膜透明性和新生血管情况，角膜组织病理变化及炎性细胞计数。结果碱烧伤造模后，对照组角膜浸润水肿明显，且随时间延长而加重，角膜基质内大量炎性细胞浸润和粗大新生血管形成。IL-1ra基因治疗组的角膜基质轻、中度水肿，角膜中性粒细胞、淋巴细胞等炎性细胞计数在不同时间点均少于对照组，角膜新生血管管径均较细。结论角膜基因原位转染可使IL-1ra在局部有效表达，抑制碱烧伤引起的角膜免疫炎症反应，为眼碱烧伤的治疗提供了新的选择。     

角膜干细胞与角膜表层新生血管

从干细胞角度探讨角膜碱烧伤后表层新生血管的成因。对大鼠角膜缘部进行碱性烧灼造成不同程度的损害，连续观察5周，结果，缘部基底细胞完全破坏者，角膜以新生血管化愈合，而保留缘部基底细胞者，角膜无新生血管化。本实验进一步证实了角膜干细胞缘部基底层定位的观点，提示干细胞对碱性烧伤后阻止角膜的新生血管化，并重建角膜表面的完整性具有重要意义。     

角膜碱烧伤后VEGF的表达与新生血管的关系

目的研究碱烧伤后角膜血管内皮生长因子（vascular endothelial growthfactor，VEGF）的表达与角膜新生血管化的关系。方法30只Sprague-Dawleg（SD）大鼠碱烧伤，诱导角膜新生血管模型。碱烧伤后不同时间形态学分析来评价角膜新生血管的情况，免疫组化及Westem blot评价角膜VEGF的表达。结果角膜碱烧伤后24hVEGF的表达开始增高，伤后4d达高峰，伤后7d VEGF的表达下降，14d后显著下降。碱烧伤后，角膜新生血管与VEGF的表达呈明显的平行关系。结论碱烧伤后大鼠角膜VEGF的表达水平与新生血管的形成有相关性，并在其中发挥重要作用。     

The relative contributions of each subset of ocular infiltrated cells in experimental choroidal neovascularisation

AIM: Choroidal neovascularisation (CNV) is a major cause of blindness in adults. The aim of this study was to investigate the role of infiltrating cells in the development of experimental CNV. METHODS: CNV was induced in C57BL/6 (B6) mice by laser photocoagulation (PC). After PC, the numbers of each subset of infiltrated cells were analysed by flow cytometry at multiple time points. Each subset (except for macrophages) was depleted by the specific antibodies in vivo. Thereafter, the area of CNV was compared between the control B6 mice and the specific antibody treated mice 7 days after PC. The CNV formation in neutrophil depleted CC chemokine receptor-2 (CCR2) knockout mice was also examined to minimise the effects of macrophages. RESULTS: In the early phase of CNV formation, a large number of neutrophils and macrophages infiltrated to the eyes. Natural killer (NK) cells and T lymphocytes were barely detected while no B lymphocytes were detected. The CNV areas did not significantly change compared between the control B6 mice and the specific antibody treated mice. However, the neutrophil depleted CCR2KO mice resulted in a reduction of CNV. CONCLUSION: Although lymphocytes and NK cells had little effect on CNV formation, neutrophils partially contributed to CNV in the absence of macrophages.     

Effect of anti-TNF-alpha on laser-induced choroidal neovascularization

OBJECTIVE: To investigate the role of TNF-alpha in the development of laser-induced choroidal neovascularization (CNV) in the mouse. METHODS: Laser photocoagulation was used to induce CNV in wild-type C57BL/6J mice by making four separate choroidal bums in each eye. Animals were treated 3 days before or after laser injury with recombinant TNF receptor P75 (etanercept, 5 microg/h, group 1, n = 12), chimeric monoclonal antibody (infliximab, 5 microg/h, group 2, n = 12) for 7 days by intraperitonealy implanted osmotic pumps. PBS was used as control (group 3, n = 12). The left eyes were removed for histopathologic examination and the right eyes were removed for flatmounts immunohistochemistry immediately after fluorescien angiography. In mice treated with medications 3 days before laser injury, left eyes were collected at 1 or 2 weeks after laser injury. In mice treated with medications 3 days after laser injury, left eyes were collected at 10 days after laser injury. CNV responses were compared by flatmount analysis of CNV-related fluorescence area and by determination of fluorescein angiographic leakage. The level of protein expression of TNF-alpha was semiquantitatively evaluated by Western blot analysis of the choroidal and RPE layer from mice with or without laser treatment. RESULTS: Western blotting demonstrated that TNF-alpha was highly expressed in choroidal and RPE cells of wild type mice 1 week after laser treatment as compared to the control mice without laser treatment. Etanercept and infliximab administrated 3 days before laser-damage significantly reduced CNV size and pathological fluorescein leakage in comparison to the control group one and two weeks after laser injury. Only etanercept administered 3 days after laser injury still significantly reduced the development of CNV lesions. Histopathological examination confirmed that CNV lesions in treated mice had smaller diameter and thinner center as compared to the control animals. CONCLUSIONS: Anti-TNF-alpha treatment reduces the size and leakage of laser-induced CNV. These results suggest the involvement of TNF-alpha in the development of laser-induced CNV and its potential use as a therapeutic agent in the age related macular degeneration.     

Expression of pigment epithelium-derived factor in experimental choroidal neovascularization

PURPOSE: To investigate the expression of pigment epithelium-derived factor (PEDF) in the rat laser-injury model of choroidal neovascularization (CNV). METHODS: Retinas were immunostained for PEDF at different times (1, 2, and 3 weeks) after laser injury. Levels of PEDF protein in the vitreous at 1, 3, 7, 14, and 28 days after laser injury were also assayed by Western blot. RESULTS: Protein levels of PEDF in the vitreous were increased during the first 7 days after CNV induction. Immunostaining for PEDF was observed throughout normal nonlasered control retinas, sham-lasered retinas, and areas remote to laser lesions, which were generally more intense in the outer nuclear layer (ONL) and less intense in the internal nuclear layer (INL). Decreased expression of PEDF was observed in flanking areas adjacent to the injury site and was confined mainly to the ONL. In the injury sites, immunostaining within the ONL was either absent or decreased for up to 3 weeks after laser injury (the duration of the study). Preadsorption of the anti-PEDF antibody with the immunizing peptide blocked specific labeling in the retina. CONCLUSIONS: These results demonstrate an inverse correlation of expression of PEDF and formation of CNV in the experimental model and suggest that decreased expression of PEDF plays a permissive role in the formation of CNV. PEDF analogues may be a reasonable treatment strategy for CNV.     

肿瘤坏死因子α抑制剂对激光诱导脉络膜新生血管的影响

目的 探讨肿瘤坏死因子α(TNF-α)在激光诱导的小鼠脉络膜新生血管(CNV)形成中的作用.方法 野生型C57BL/6J小鼠36只(72只眼),每只眼视网膜上做4个光凝斑诱导CNV生成.小鼠分别于光凝前3 d或后3 d腹腔内植入渗透泵,给予TNF-α抑制剂依那昔普(5μg/h,n=12)或英利西单抗(5μg/h,n=12),持续7 d,对照组给予PBS(n=12).光凝前3 d的用药组分别于光凝后1和2周,光凝后3 d的用药组于光凝后10 d做荧光素眼底血管造影(FFA),之后立刻取左眼行视网膜组织学检查,右眼制作脉络膜平片,免疫组化方法 标记内皮细胞,测定荧光素渗漏面积及脉络膜平片CNV相关荧光面积,比较CNV病变的大小及程度.用免疫印迹法分析比较小鼠光凝前后视网膜色素上皮层及脉络膜上TNF-α蛋白的表达.结果 光凝后1周,免疫印迹法结果 显示小鼠脉络膜及视网膜色素上皮层TNF-α表达增加.光凝前3 d用药,光凝后1周,荧光素渗漏面积为(0.74±0.33)×104 像素,2周时则为(0.63±0.20)×104 像素,与对照组[(2.61±0.80)×104 像素]比较均显著减少(t=3.69,3.56;P＜0.05).光凝后1周对照组、依那昔普组和英利西单抗组CNV面积分别为(3.61±0.93)×105、(1.89±0.62)×105和(2.14±0.72)×105像素,与对照组比较,差异均有统计学意义(t=3.10,2.51;P＜0.05.但光凝后3 d用药,则只有依那昔普能显著抑制CNV病变.组织病理学检查进一步证实,治疗组小鼠的CNV病变直径及厚度小于对照组.结论 TNF-α参与激光诱导的CNV的形成.TNF-α抑制剂能抑制激光诱导的CNV的形成及渗漏.(中华眼科杂志,2008,44:200-206)     

Choroidal neovascularization after accidental macular damage by laser

A 30-year-old male physics professor was examined 2 months after being accidentally hit by a laser beam in his left eye. He complained of abrupt vision loss and central scotoma after the laser accident,with stabilization of the vision thereafter. At presentation, he presented best-corrected visual acuity of 6/18 in the left eye. Fundoscopy disclosed a slightly elevated foveal brownish lesion,surrounded by a subtle subretinal haemorrhage. Fluorescein angiography demonstrated a hyperfluorescent foveal lesion with staining and a slight leakage in the late phase, characterizing a fibrovascular choroidal neovascularization (CNV). Optical coherence tomography showed a discrete increase in retinal thickness and a subretinal fibrotic CNV. Visual acuity remained stable during the follow up(4 months). CNV after laser injury is rare. The evolution of this case suggests that CNV, after an accidental laser injury,in a healthy macula of a young patient might have a self-limited course and a relatively good prognosis.     

Macrophage depletion inhibits experimental choroidal neovascularization

OBJECTIVE: To investigate the role of macrophages in the development of laser-induced choroidal neovascularization (CNV) by selective depletion with liposomal clodronate (Cl(2)MDP-LIP). METHODS: Laser photocoagulation was used to induce CNV in wild-type C57BL/6J mice. Animals were treated with intravenous (IV) and/or subconjunctival (SC) Cl(2)MDP-LIP or PBS-LIP at the following time points: 2 days before, immediately after, 2 days before and immediately after, or 2 days after laser injury. CNV responses were compared on the basis of en masse volumetric measurements and fluorescein angiography after laser photocoagulation. Macrophages were identified by immunostaining for F4/80, and vascular endothelial growth factor (VEGF) expression was quantified by ELISA. RESULTS: Macrophages invaded the site of laser injury within 1 day of photocoagulation and peaked at 3 days. IV Cl(2)MDP-LIP significantly decreased the volume of CNV and angiographic leakage when administered 2 days before and/or immediately after laser injury, but not when administered 2 days after injury. SC Cl(2)MDP-LIP significantly decreased lesion volume when coadministered with IV PBS-LIP but not IV Cl(2)MDP-LIP. IV Cl(2)MDP-LIP was significantly more beneficial when administered 2 days before laser injury than immediately after, but combining SC Cl(2)MDP-LIP with IV treatment eliminated this difference. Reduction in CNV volume correlated with VEGF protein levels and number of infiltrating macrophages. CONCLUSIONS: Generalized macrophage depletion reduced the size and leakage of laser-induced CNV and was associated with decreased macrophage infiltration and VEGF protein. These findings define the role of the macrophage as a critical component in initiating the laser-induced CNV response.     

Inhibition of TNF-alpha reduces laser-induced choroidal neovascularization

To investigate the role of the TNF-alpha in the development of laser-induced choroidal neovascularization (CNV) in a mouse model. Four separate laser burns were applied to induce ruptures of Bruch's membrane and subsequent choroidal neovascularization in C57BL/6J mice. TNF-alpha protein expression was semiquantitatively assessed by Western blot analysis of the choroidal and RPE layer from mice with or without laser treatment. To investigate the effect of TNF-alpha inhibition on CNV formation, animals were treated for 7 days via intraperitonealy implanted osmotic pumps either 3 days before or after laser injury with recombinant TNF receptor P75 (etanercept), a chimeric monoclonal antibody (infliximab), or a purified rat anti-mouse/rat TNF monoclonal antibody (TNF-mAb), respectively. Fluorescein angiography, flat-mount preparations, and histopathology were performed at day 7, 10, or 14 after laser treatment. Western blotting demonstrated that TNF-alpha expression was 4.57-fold higher in the choroid and RPE one week after laser injury compared to control mice without laser. When evaluated one and two weeks after laser injury, etanercept and infliximab given from the 3rd day before laser-damage significantly reduced CNV size and pathological fluorescein leakage compared to the control group after laser treatment only. The inhibitory effect of the monoclonal TNF-alpha antibody on CNV formation was evident two weeks after photocoagulation but not after one week. Only etanercept administered 3 days after laser injury still reduced significantly the development of CNV lesions. Histopathology confirmed that CNV lesions in treated mice were smaller in size compared to the control animals without TNF inhibitor treatment. In conclusion, anti-TNF-alpha treatment with different inhibitors reduces both the size and the leakage of laser-induced CNV. These results suggest the involvement of TNF-alpha in the development of laser-induced CNV and its potential use as a therapeutic agent in the age-related macular degeneration.     

外源性肿瘤坏死因子α对碱烧伤诱导角膜新生血管的影响及机制

目的探讨外源性肿瘤坏死因子α（TNF—α）局部干预对碱烧伤诱导角膜新生血管（CNV）形成的影响及内在机制。方法BALB／c小鼠45只,利用碱烧伤法制作左眼CNV模型。根据实验设计．分3组实验进行研究。①CNV模型小鼠15只,随机分为3组,每组5只。自伤后分别给予100、500μg／ml TNF—α（实验组）或0-2％透明质酸钠（HA,对照组）点眼1周。于碱烧伤后第14天处死小鼠取眼球,免疫组织化学法检测各组角膜组织中CD31的表达,计数微血管密度（MVD）,分析TNF-α对碱烧伤CNV形成的作用。②CNV模型小鼠20只．随机分为2组,每组10只。实验组给予100μg／mlTNF一仅点眼,对照组给予0．2％HA点眼。分别于伤后第2天和第4天随机取5只小鼠处死取角膜．RT—PCR法检测角膜组织中血管内皮生长因子（VEGF）mRNA的表达情况,分析TNF—α对碱烧伤角膜中VEGF表达的影响。③利用二氯亚甲二磷酸脂质体（Cl2MDP—lip）射制作小鼠巨噬细胞特异剔除模型,10只BALB／c小鼠随机分为Cl2MDP—lip实验组及PBS—lip对照组,每组5只。所有小鼠自碱烧伤后均给予100μg／mlTNF-α滴眼1周于.伤后第14天拍照记录CNV形成情况,图像分析软件测算CNV长度及面积,分析巨噬细胞在TNF—α调控碱烧伤后CNV形成中的作用。结果①碱烧伤后第14天,100μg／mlTNF-α组CNV形成较对照组明显增多．而500μg／ml TNF-α组CNV形成与对照组差异不明显。整张切片和热点区域MVD值,100μg／ml TNF-α组为63．25±9．75和114．94±12．93,500μg／ml TNF-α组为39．53±10．41和108．04±23．55．0．2％HA对照组为30．99±7．08和73．81±13．80和100μg／mlTNF—α组与对照组比较,差异有统计学意义（P〈0．05）,而500μg／mlTNF-α组与对照组相比差异无统计学意义（19〉0．05）。②碱烧伤后第2天和第4天VEGFmRNA与β—actin的比值,100μg／mlTNF-α组为0．40±0．12和1,51±0．21,0．2％HA对照组为0,31±0．10和0．58±0．30。两组差异均有统计学意义（P〈0．05）。⑧碱烧伤后第14天,Cl2MDP—lip组CNV形成较对照组明显减少,Cl2MDP—lip组的CNV长度和面积分别为（0．84±0．10）mm和（6．64±1．19）mm^2,PBS—lip对照组为f1．37±0．24）mm和（12．25±1．33）mm^2,两组差异有统计学意义（P〈0．01）.结论外源性TNF-α可通过上调碱烧伤角膜组织中VEGF表达来促进CNV的形成,其促进碱烧伤CNV形成机制主要是通过巨噬细胞起作用．     

Targeted disruption of the CD18 or ICAM-1 gene inhibits choroidal neovascularization

PURPOSE: To investigate the role of the leukocyte adhesion molecules CD18 and intercellular adhesion molecule (ICAM)-1 in the development of choroidal neovascularization (CNV). METHODS: Laser photocoagulation was used to induce CNV in wild-type C57BL/6J mice and species-specific counterparts with targeted homozygous disruption of the CD18 or ICAM-1 gene. Expression of CD18 and ICAM-1 after laser injury was assessed by immunostaining. CNV responses were compared on the basis of en masse volumetric measurements obtained by confocal microscopy 2 weeks after laser injury and by determination of fluorescein angiographic leakage at 1, 2, and 4 weeks after laser injury. RESULTS: The site of laser injury showed upregulation of ICAM-1 and invasion by CD18-positive leukocytes within 1 day of laser injury. Significantly fewer lesions exhibited fluorescein leakage defined to be pathologically significant in CD18-deficient mice at weeks 1, 2, and 4 weeks and in ICAM-1-deficient mice at 1 and 4 weeks, compared with the control. There were a significantly greater number of lesions without fluorescein leakage in CD18-deficient mice than in the other two groups at all time points. The volume of CNV in CD18- and ICAM-1-deficient mice was significantly less than in wild type. CONCLUSIONS: These data suggest a nonredundant role for leukocyte adhesion to vascular endothelium in the development of laser-induced choroidal neovascularization.