【摘要】 目的 在实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)模型中,比较常规T2加权成像(T2weighted imaging,T2WI)、钆二乙三胺五醋酸(gadoliniumdiethylenetriamine pentaacetic acid,GdDTPA)和超顺磁性氧化铁(superparamagnetic iron oxide,SPIO)增强图像之间的差异,探讨巨噬细胞在多发性硬化(multiple sclerosis,MS)炎性活动病灶中的细胞学标志。方法 在EAE模型临床症状的亚临床期、初发期、高峰期,13只复发缓解(relapsingremitting,RR)EAE大鼠模型组和13只正常对照组大鼠在注入对比剂之前均行常规T2WI扫描,接着分别在其尾静脉注入GdDTPA后5 min行T1加权成像(T1weighted imaging,T1WI),再注入SPIO,24 h后行T2WI扫描。扫描完毕后立即处死大鼠取脑,行脑组织切片的ED1免疫组织化学染色和Prussian blue染色。结果 EAE模型组大鼠在第11天出现临床症状(初发期),第14天达到高峰期;MRI检查:SPIO增强图像对EAE病灶的显示较常规T2WI和GdDTPA增强图像好。病理学检查:ED1染色,在SPIO显示为低信号的区域内出现了炎症细胞(以巨噬细胞为主)浸润;Prussian blue染色示病灶内巨噬细胞胞质内出现了蓝染颗粒,沉积部位与T2WI上低信号区对应。对照组大鼠均无异常。结论 SPIO较GdDTPA更好地显示EAE模型中炎性活动性病灶内血管周围以巨噬细胞为主的浸润。
PURPOSE:To measure the concentration changes of tumor necrosis factor a (TNF-alpha;)in vitreous during the development of experimental PVR induced by macrophages and explore the initial and mediated factors which stimulate the cellular proliferation. METHODS:Rabbit PVR model was induced by macrophages and the vitreous was taken at the 7th,14th,21st and 28th day and 4 eyes in each group. The TNF-alpha; levels in vivreous of the above examinated and control eyes were measured with an ELISA kit. RESULTS:The TNF-alpha; level in the vitreous reached its peak 434mu;g/ml at 21st day in the mod-el, then rappidly decreased to 122mu;g/ml at 28th day. CONCLUSION:The changes of TNF-a in the vitreous of the PVR model were parallel to the natrual phases of the development of PVR,indicating TNF-alpha; may play an important role in initiating and mediating the inflammation and cellular proliferation in the vitreous. (Chin J Ocul Fundus Dis,1997,13: 231-233)
PURPOSE: To produce monoclonal antibodies directed against tumor-associated antigens expressed of retinoblastoma-derived tissue culture cell line SO-RBS0. METHODS:Hybridization was performed and the specificity of the antibody was tested by immunofluorescent and immunohistochemical methods. RESULTS:Two hybridomas secreted specific monoclonal antibody against retinoblastoma cells were produced ,and the isotype of the monoclonal antibody was IgG2a CONCLUION:The monoclonal antibodies were specific and highly active against retinoblastoma cells and might be used as immunoconjugate.
Objective To observe the effect of diabetic retinopathy on endothelial progenitor cells (EPCs) from peripheral blood. Methods Sixty male Wistar rats were divided into control group and diabetes group. The rats in diabetes group were induced with streptozotocin (STZ) injection for diabetic retinopathy model. Flow cytometry was used to identify and count the number of EPCs from peripheral blood at 1 week, 1, 3 and 6 months after injection. All eyeballs were examined by hematoxylin and eosin (HE) staining, periodic acidSchiff's (PAS) staining of trypsin-digested retinal vessels flat preparation and transmission electron microscope. EPCs count, and the relationship between DR morphological changes and EPCs count were compared and analyzed. Results The quantity of EPCs from peripheral blood at 1 week, 1, 3 and 6 months after STZ injection were 25plusmn;7, 28plusmn;8, 39plusmn;7, 43plusmn;7 cells per 200 000 monocytes respectively, which decreased compared with the control group 45plusmn;4 cells per 200 000 monocytes (F=8.933,Plt;0.01). The quantity of EPCs was gradually increased at 1 week, 1, 3 and 6 months after STZ injection, accompanied with responsive pathological changes of retinal structure and vessels. The thickness of retina at 1 week and 1 month after injection were reduced slightly. The number of retinal ganglion cells reduced, with the time passing by. Endothelial cells were edema, mitochondrial was swollen, capillary basement membrane was thicken, lumen was significant stenosis, lumen occlusion and retinal artery aneurysm were observed at 6 months after STZ injection. Conclusion The number of EPCs increases gradually throughout the development of DR.
Objective To observe the inhibition effect of the hypoxia inducible factor-1alpha; (HIF-1alpha;) specific siRNA on the expression of vascular endothelial growth factor (VEGF) mRNA in retinal tissues in diabetic rat. Methods This is a randomized controlled study. HIF-1alpha; specific siRNA recombinant plasmid was built in pSilencer2.1-U6neo vector. Fifty-four healthy Sprague Dawley (SD) rats were divided into control group (15 rats) and experimental group (39 rats). The experimental rats were induced with streptozotocin injection for diabetic retinopathy model, and then randomly divided into diabetic retinopathy (DR) group (15 rats), vector group (12 rats) and gene therapy group (12 rats). LipofectamineTM2000 mixed with pSilencer2.1-U6neo plasmid or HiF-1alpha; siRNA plasmid were injected into the vitreous in the vector group and gene therapy group respectively. Nothing was transfected into DR and control group. The expression of VEGF mRNA in retinas was measured by real-time RT-PCR. The inhibition efficiency of VEGFmRNA was calculated at 24, 48, 72 hours and 1 week after injection respectively. Significant differences between groups were evaluated by oneway analysis and LSD-t analysis. Results HIF-1alpha; siRNA recombinant plasmid was confirmed by enzyme digestion and sequence analysis. Real-time RT-PCR revealed that the expression of VEGFmRNA was faint in the control group, increased obviously in the DR and vector group, decreased in the gene therapy group. There was no statistically significant between DR and vector group (t=0.669,0.142,0.151,0.025;P=0.514,0.889,0.882,0.980). The expression of VEGFmRNA in the gene therapy group were obviously decreased compared with DR and vector group (t=8.768, 13.695, 11.285, 8.253;P=0.000). The inhibition efficiency of VEGFmRNA was 32.76%, 43.60%, 47.70%, 50.86% at 24, 48, 72 hours and 1 week after injection. Conclusions The expression of VEGFmRNA can be efficiently inhibited by HIF-1alpha; siRNA recombinant plasmid.
Objective To observe the degradation regulation of ubiquitinproteasome inhibitor nuclear factor kappa;B(NF-kappa;B)and its inhibitory signal protein Ikappa;B kinase in earlier period diabetic retinopathy(DR),and the effects on retinal ganglion cells (RGC) apoptosis.Methods Forty healthy adult Wistar rats were randomly divided into control (group A),DR(group B),DR+lowconcentration MG132 treated (group C)and DR+high concentration MG132 treated(group D)groups,10 rats in each group.After 6 and 8 weeks,the results of body masses and fasting blood glucose (FBG) were detected,the expression of NF-kappa;B and Ikappa;B were observed by immunohistochemistry respectively.RGC apoptosis was assessed by the terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labelling (TUNEL) method.Results The expression of NF-kappa;B was upregulated in group B compared with group A,its expression decreased in group D compared with group B; but the expression of Ikappa;B was contrary to NF-kappa;B; RGC apoptosis was followed a similar pattern with the expression of NF-kappa;B; the differences among them were statistically significant (P<0.01).Compared the expression of NF-kappa;B,Ikappa;B and RGC apoptosis in group C and D, there were no statistically significant differences(P>0.05).Conclusion Ubiquitin-proteasome inhibitor MG132 can block the activation of NF-kappa;B,inhibit ubiquitination of Ikappa;B degradation and RGC apoptosis.