Effect of olfactory ensheathing cell transplantation on myelin repair and motor function in a rat model of experimental allergic encephalomyelitis

BACKGROUND： Olfactory ensheathing cell transplantation can activate axonal regeneration and enhance myelin repair, which are beneficial for treating demyelinating diseases. OBJECTIVE： To explore the effects of olfactory ensheathing cell transplantation on myelin repair, synaptophysin expression, and motor function in a rat model of experimental allergic encephalomyelitis. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Laboratory of Provincial Hospital affiliated to Shandong University between August 2006 and September 2007. MATERIALS： Dibenzylamine （Hoechst 33342）, luxol fast blue, and rabbit anti-rat synaptophysin antibody were provided by Sigma, USA. METHODS： Olfactory ensheatbing cells extracted from neonatal Wistar rats were cultured for 10-14 days and labeled with dibenzylamine. Spinal cord extracted from a healthy guinea pig was homogenized and equally mixed with complete Freund＇s adjuvant; thereafter, the mixture was intracutaneously injected into two posterior voix pedis of healthy male Wistar rats to establish models of experimental allergic encephalomyelitis. Rats were randomly divided into a control encephalomyelitis group and an olfactory ensheathing cell transplantation group, 36 rats in each group. Physiological saline （2 μ L） or an olfactory ensheathing cell suspension （2 μ L） was separately injected along lateral cerebral ventricle at day 7 post-model induction. MAIN OUTCOME MEASURES： The migration and distribution of olfactory ensheathing cells were observed under fluorescence microscopy; myelin repair was detected using hematoxylin-eosin staining and luxol fast blue staining; synaptophysin expression was measured using immunohistochemical staining; motor function was evaluated using a motor function scale. RESULTS： Olfactory ensheatbing cells could survive in vivo and migrate to the distal end of the transplant focus and spinal cord, and survived 21 days. Hematoxylin-eosin staining and luxol fast blue staining indicated that myelin in the transplantation group was intact, and the inflammatory focus gradually disappeared. Transplantation increased synaptophysin expression （P 〈 0.05 versus control） and motor function （P 〈 0.05）. CONCLUSION： Olfactory ensheathing cell transplantation can promote myelin repair, increase synaptophysin protein expression, and ameliorate motor function in a rat model of experimental allergic encephalomyelitis.

Immunity phenomena following olfactory ensheathing cell transplantation into experimental allergic encephalomyelitis rat brain

Olfactory ensheathing cells （OECs） can promote axonal regeneration and remyelination for the treatment of spinal cord injury. OECs can also treat experimental allergic encephalomyelitis （EAE）, but it remains unclear whether OECs might be rejected by the immune system in the brain including the destruction of the blood-brain barrier under inflammation, the release of inflammatory factors, the activation of local antigen-presenting cells （e.g., microglia cells） and antigen drainage. We found that OECs expressed major histocompatibility complex （MHC）-I molecules on the cell surface, barely expressed MHC-II, but MHC-II could be induced by interferon-v, suggesting that OECs have certain immunogenicity. When OECs were transplanted into normal animal brains, no OECs were phagocytosed by dendritic cells in the cervical lymph node, and OECs did not induce lymphocyte proliferation, which indicates that OECs share some immune privilege under normal conditions. However, OECs in the rat EAE brain were phagocytosed by dendritic cells in the cervical lymph node and enhanced lymphocyte proliferation. These findings suggest that OECs are rejected because of increased immunogenicity in EAE brain, and that brain inflammation, in particular activated dendritic cells, may be a prerequisite for rejecting OECs.

PD-L1 is increased in the spinal cord and infiltrating lymphocytes in experimental allergic encephalomyelitis

Experimental allergic encephalomyelitis is a mouse model of human multiple sclerosis with similar pathology and pathogenesis. Thl cells play an important role in the pathogenesis of experimental allergic encephalomyelitis. This study determined the potential effect of programmed cell death 1 ligand 1 in the pathogenesis of experimental allergic encephalomyelitis induced by injecting myelin oligodendrocyte glycoprotein, complete Freund＇s adjuvant and Bordetella pertussis toxin into C57BL/6J mice. Experimental allergic encephalomyelitis mice developed disease and showed in- flammatory changes in the central nervous system by hematoxylin-eosin staining of spinal cord pathological sections, demyelination by Luxol fast-blue staining and clinical manifestations. The expression of programmed cell death 1 ligand 1 in mice was detected by immunohistochemistry, flow cytometry and western blot anatysis. The expression of programmed cell death 1 ligand 1 in the spinal cord and splenocytes of mice was significantly increased compared with normal mice. Our findings suggest the involvement of programmed cell death 1 ligand 1 in the pathogenesis of ex- perimental allergic encephalomyelitis and suggest this should be studied in multiple sclerosis.

Effect of neuropeptide Y on white matter demyelination and serum interleukin-4 and gamma-interferon levels in the guinea pig with experimental allergic encephalomyelitis

BACKGROUND： Neuropeptide Y （NPY） may influence differentiation of Th cells immunological pathology of experimental allergic encephalomyelitis （EAE） is differentiation of Th cells It is assumed that the related to abnormal OBJECTIVE： To investigate the effect of NPY on white matter demyelination, the serum levels interleukin-4 （IL-4） and gamma-interferon （IFN-γ ）, as well as EAE pathogenesis in an EAE guinea pig model following NPY injection into the lateral cerebral ventricle. DESIGN, TIME AND SETTING： A randomized controlled animal study, which was performed in the Infection Immunity Animal Laboratory, Affiliated Hospital of Luzhou Medical College, China, from October 2005 to April 2006. MATERIALS： Thirty healthy female guinea pigs of 8-12 weeks of age, and 10 healthy female rats of three months of age were used. NPY was provided by Sigma Company, USA. NPY kit was provided by Beijing Huaying Biotechnology Institute, China. METHODS： Thirty guinea pigs were randomly divided into three groups： normal control group, EAE model group, and NPY intervention group （n =10 per group）. Normal control group and EAE model group： Saline （10μ L, once） was injected into the lateral cerebral ventricle. After one week, the same volume of Freund＇s adjuvant complete was either injected subcutaneously into two post-palms or EAE was modeled. NPY intervention group： EAE was modeled after one week and NPY was injected （10 μ L of 6 nmol NPY, once） into the lateral cerebral ventricle. Myelin basic protein （MBP） antigen made from rat spinal cord homogenate and Freund＇s adjuvant complete were injected subcutaneously into both post-palms （0.2 mL per palm） to establish the EAE model. MAIN OUTCOME MEASURES： White matter demyelination of the cerebrum, cerebellum, brain stem, and spinal cord were observed by light microscopy after HE staining. Levels of serum IFN-γ and IL-4 were detected by the double antibody sandwich ABC-ELISA technique. NPY content was detected by radioimmunoassay. RESULTS： Pathological alterations in the NPY intervention groups were reduced compared to those in the EAE model group, suggesting a reduction and remission of white matter demyelination with NPY treatment. When compared to the model group, the serum IL-4 level was increased in the NPY intervention group during the high-frequent EAE stage （P 〈 0.01）, but the serum IFN-γ level was decreased （P 〈 0.01）. Furthermore, the EAE latency was prolonged （P 〈 0.01）, the neurological scores were decreased in the high-frequent EAE stage （P 〈 0.01）, and the death rate was decreased （P 〈 0.05）. NPY content and the serum IL-4 level at the peak stage were positively correlated with those in the latent phase （r =0.863-0.900, P 〈 0.01）, but negatively correlated with neurological scores at the peak stage （r=- -0.068 to -0.863, P 〈 0.05-0.01）. The IFN-γ level at the peak stage was negatively correlated to that in the latent phase （r = -0.683-0.650, P 〈 0.05）, but positively correlated to neurological scores at the peak stage （r =0.975, 0.845, P 〈 0.05）. CONCLUSION： NPY injection into the lateral cerebral ventricle can promote the secretion of IL-4, inhibit the production of IFN-γ, relieve white matter demyelination, and inhibit EAE attack in an experimental model of EAE.

EAE （Experimental Autoimmune Encephalomyelitis）, Corticotropin-Releasing Factor and the Blood Brain Barrier

EAE （experimental autoimmune encephalomyelitis） is an established, inducible animal model employed in the study of MS （multiple sclerosis） characterized by inflammation, BBB （blood brain barrier） malfunction, demyelination and neuronal disruption. CRF （corticotropin releasing factor） is a neuropeptide critically associated with immune function, BBB permeability, and the hypothalamic-pituitary-adrenal axis. Potential CRF targets in the brain include astrocytes, as well as endothelial cells of cerebral microvessels, since they have been reported to express CRFR （CRF receptors）. Further, both of these cell types function critically in regulating BBB permeability. CRF-BP （CRF binding protein） is also expressed in both neurons and glial cells. Changes in the cortical CRF system could be a contributing factor to the BBB disruption associated with MS/EAE and has been suggested to play a protective role against cytokine-induced inflammation. The current study assessed alterations associated with the C57BL/6 mouse model of EAE in the cortical CRF system and correlated these events with changes to the microvascular unit. Immunohistochemical confocal microscopy was used to analyze the distribution of CRF, CRF-BP, and CRFR in the mouse cerebral cortex. The authors observed a reduction in detectable CRF immunofluorescence in the EAE motor cortex, an increase in CRFBP immunoreactivity in EAE astrocytes and a concurrent reduction in astrocytic CRFR immunofluorescence. Staining techniques were used to visualize astrocytes/microvessels to document alterations in BBB integrity. Changes in the CRF system were associated with a modification of the blood brain barrier as manifested by a poorly defined astrocytic barrier in EAE microvessels. Evidence suggests that manipulation of CRF signaling pathways offers an intriguing target for interventional therapies designed to modify BBB permeability that may be beneficial for treating disease states such as MS.

Effect of oxymatrine on interferon-gamma and tumor necrosis factor-alpha serum levels in an experimental rat model of autoimmune encephalomyelitis

BACKGROUND： Studies have demonstrated that experimental autoimmune encephalomyelitis （EAE） onset correlates with increased interferon-v （IFN-γ） and tumor necrosis factor-α （TNF-α） expression. Oxymatrine （OM） has been shown to inhibit autoimmune responses, but there are no reports showing that it could prevent the development of EAE. OBJECTIVE： To observe the effect of OM on serum levels of IFN-γ and TNF-α in a rat model of EAE.DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the Experimental Animal Center of Henan Academy of Chinese Medicine and at the Key Disciplines Laboratory Clinical Medicine of Henan Province between July and December 2008. MATERIALS： OM was purchased from Chia-tai Tianqing Pharmaceutical, China; complete Freund＇s adjuvant was purchased from Sigma, USA. METHODS： Forty female Wistar rats were randomly assigned to four groups： EAE model （M）, low-dose OM treatment （OM-L）, high-dose OM treatment （OM-H）, and normal control （N, no immunization）, with 10 rats in each group. EAE was established in the M, OM-L, and OM-H groups following immunization with Guinea pig spinal cord homogenate and complete Freund＇s adjuvant. The M and N groups were intraperitoneally injected with normal saline （6.7 mL/kg per day）, the OM-L group received an intraperitoneal injection of OM （100 mg/kg per day）, and the OM-H group received OM （150 mg/kg per day）. MAIN OUTCOME MEASURES： At 16 days after immunization, the degree of histopathological changes in the spinal cord was assessed by hematoxylin-eosin stanining. Enzyme-linked immunosorbent assay was used to detect serum levels of IFN-γ, and radioimmunoassay was utilized to determine serum TNF-α level. Neurological scores were measured on a daily basis according to a 0-5 scale. RESULTS： Daily injections of OM, both high and low doses, resulted in decreased neurological scores in EAE rats （P〈0.01）, as well as reduced cellular infiltration in the spinal cord and decreased levels of serum IFN-γ and TNF-α （P〈 0.01）. CONCLUSION： OM reduced the onset and severity of EAE, which correlated with decreased IFN-γ and TNF-α expression.

Eotaxin-2 blockade ameliorates experimental autoimmune encephalomyelitis

AIM： To study the effect of blocking the eo-2 pathwaon the development and severity of experimental autoimmune encephalomyelitis （EAE）. METHODS： We produced mAb directed against eo-2named D8. MOG35-55 induced-EAE mice were dailintravenously injected with either 25 μg or 100 μg D8or with vehicle control alone [phosphate-buffered saline（PBS）], starting from day 0 post immunization and weremonitored for EAE clinical score （n = 10 in each group）Mice were sacrifced on day 58 and their sera were assessed for the presence of anti-myelin oligodendrocyteglycoprotein （anti-MOG） antibodies autoantibodies, awell as for the profle of pro-infammatory cytokines andchemokines. Histological analysis of brain sections waperformed by hematoxylin and eosin staining.RESULTS： Daily treatment of EAE induced mice with D8 signifcantly decreased the severity of EAE symp-toms. Treatment with both concentrations of D8 ame-liorated EAE symptoms compared to PBS treated mice, starting from day 42 post immunization （0.89 ± 0.35 in D8 25 μg and D8 100 μg treated groups vs 2.11 ± 0.38 in the PBS treated group, P = 0.03）. A signifcant im-provement in EAE clinical score compared to total IgG treated mice was observed with the higher concentra-tion of D8 （0.81 ± 0.38 in D8 100 μg treated group vs 2.11 ± 0.31 in IgG1 treated group, on day 56 post immunization, P = 0.04）. D8 treated mice with EAE did not signifcantly exhibit lower sera levels of anti-MOG autoantibodies compared to IgG-treated mice. How-ever, they expressed lower sera levels of the pro-in-fammatory cytokines： tumor necrosis factor （7.8 ± 0.2 pg/mL in D8 100 μg treated mice vs 19.9 ± 3.4 pg/mL in IgG treated mice, P = 0.005） and interferon-gamma （1.4 ± 0.6 pg/mL in D8 100 μg treated mice vs 3.6 ± 0.4 pg/mL in IgG treated mice, P = 0.02）, as well as reduced levels of the chemokine macrophage che-moattractant protein-1 （27.2 ± 3.1 pg/mL in D8 100 μg treated mice vs 63.7 ± 12.3 pg/mL in IgG treated mice, P = 0.03）. These fndings indicate that blocking the eo-2 pathway in EAE may affect not only eosino-phil infltration into the central nervous system （CNS）, but also have an effect on monocytes and T cells, but not humoral, mediated responses. Histological analysis of the brains of D8 treated mice with EAE support that this treatment decreases immune cells infltrates in the CNS.CONCLUSION： Taken together, these fndings suggest a role for eo-2 in EAE pathogenesis and consequen-tially may support a therapeutic potential of anti-eo-2 neutralizing mAb in multiple sclerosis.

新型重组免疫毒素DT390-mRantes治疗小鼠EAE的初步研究

目的:构建一种含有重组免疫毒素DT390-mRantes(白喉杆菌外毒素390片段-活化T细胞表达与分泌调节因子)的真核表达质粒,并用于治疗小鼠实验性自身免疫性脑脊髓炎(EAE)。方法:利用自提的MBP诱导C57BL/6小鼠产生EAE,将mRantes导入含有DT390的真核表达质粒SRα中,经阳离子纳米脂质体包被后,治疗小鼠EAE,同时对其临床症状、脑部病理改变、外周血相关细胞因子及T/B细胞比例进行检测,了解该重组免疫毒素的治疗效果。结果:成功构建真核表达质粒DT390-mRantes-SRα,治疗组小鼠临床症状减轻,脑部特异性淋巴细胞浸润减少,外周T细胞相关细胞因子表达降低,T/B细胞比例降低。结论:新型重组免疫毒素DT390-mRantes治疗小鼠EAE有较为明显的效果,为治疗人的多发性硬化(MS)提供有益的借鉴。

EAE大鼠SFO血红素氧合酶-1基因和蛋白表达的变化

目的:探讨实验性变态反应性脑脊髓炎(EAE)时,大鼠血红素氧合酶-1(HO-1)在穹隆下器(SFO)中的变化,为证明SFO是感受外周信息物质的早期位点之一提供依据。方法:分别用免疫组化和原位杂交方法,观察了完全福氏佐剂-豚鼠脊髓匀浆(CFA-GPSCH)诱导大鼠EAE1d、7d、14d、21d时SFO部位HO-1基因和蛋白表达的动态变化,并分析了与症状之间的相关性。结果:对照组大鼠脑仅有少量HO-1基因和蛋白表达;实验组大鼠诱导EAE后,伴随着大鼠EAE症状及脑组织病理损伤的出现和进行性加重,其HO-1基因和蛋白表达量逐渐增高;在诱导后1d,SFO部位即出现HO-1mRNA和蛋白表达,而其他脑区变化不明显;7d时进一步增多;14d时,HO-1蛋白表达至高峰。HO-1阳性细胞主要位于脉络丛、穹隆下器、血管“套袖样”病灶的周围,与EAE病变部位一致,此时大鼠EAE病情最重、体重减轻最显著、脑组织病理改变最明显;21d时脑组织HO-1基因和蛋白表达量逐渐下降,大鼠EAE症状也逐渐恢复。应用HO-1特异性抑制剂Snpp9后,大鼠EAE症状和脑组织病变明显减轻,说明脑组织HO-1的动态变化与EAE症状及脑组织损伤密切相关。结论:在EAE发病早期,SFO即已经感受到外界的氧化应激变化,SFO可能是外周免疫信息物质向中枢神经系统传递的重要而早期的通道之一;其次,应用HO-1抑制剂可能成为防治该病的有效方法之一。

EAE大鼠脑中ICAM-1、VCAM-1的检测及意义

目的:实验性变态反应性脑脊髓炎(experimentalallergicencephalomyelitis ,EAE)是研究多发性硬化(multiplesclerosis,MS)发病机制及探索治疗的理想动物模型。本实验通过检测急性EAE模型大鼠脑中细胞间粘附分子- 1(intercellularadhe sionmolecule - 1,ICAM - 1)、血管细胞间粘附分子- 1(vascularcelladhesionmolecule -l,VCAM - 1)的表达以探讨粘附分子在EAE发病过程中的作用及意义。方法:以豚鼠脊髓匀浆加完全福氏佐剂作为抗原,给予Wistar大鼠四足皮内注射,建立EAE模型。应用免疫组织化学技术检测EAE大鼠脑中ICAM - 1、VCAM - 1的表达。与对照组对比作成组t检验来分析其表达是否具有统计学意义。结果:ICAM - 1,VCAM - 1在EAE大鼠脑血管内皮细胞的表达与正常对照组比较有显著性差异(P <0 .0 1)。结论:EAE模型建立方法稳定、可靠。ICAM - 1、VCAM -

雷公藤多苷联合地塞米松对EAE中TLRs/NF-κB信号通路的作用

目的:探讨雷公藤多苷联合地塞米松对实验性变态反应性脑脊髓炎(EAE)的治疗效果及其作用途径。方法:所有实验动物被分为空白对照组、EAE组、治疗组1(地塞米松)和治疗组2(雷公藤多苷联合地塞米松)。比较各组平均临床评分;分别采用实时定量RT-PCR和免疫组化法检测不同组别脑组织中TLR4和TLR9mRNA和蛋白含量,免疫组化法检测NF-κB p65蛋白的表达;采用ELISA法检测外周血中TNF-α、IL-1β和IL-6含量的变化。结果:各治疗组平均临床评分较EAE组均降低(P<0.05);治疗组2较治疗组1平均临床评分降低(P<0.05)。在发病高峰期,EAE组TLR4和TLR9 mRNA及蛋白表达较空白对照组增高,而各治疗组较EAE组降低(均P<0.05);EAE组NF-κB p65阳性表达率较各治疗组升高(P<0.05);各治疗组炎症细胞因子TNF-α、IL-1β和IL-6含量较EAE组降低(P<0.05)。治疗组2与治疗组1比较,上述各指标差异显著(均P<0.05),且雷公藤多苷与地塞米松具有交互作用(F=75.749,P<0.01)。结论:TLRs/NF-κB信号通路可能参与了EAE的发病过程;雷公藤多苷联合地塞米松具有明显改善EAE临床症状的效果,其可能通过抑制TLRs/NF-κB信号通路发挥抗炎及免疫抑制双重疗效。

右归丸对EAE小鼠Th17细胞分化的影响

目的探讨右归丸对实验性自身免疫性脑脊髓炎小鼠(experimental autoimmune encephalomyelitis,EAE)Th17细胞分化的影响。方法建立髓鞘少突胶质细胞糖蛋白35-55(myelin oligodendrocyte glycoprotein peptide 35-55,MOG35-55)诱导C57BL/6小鼠EAE模型,随机分为模型组、泼尼松龙组,右归丸组,并设正常对照组。观察小鼠的发病情况、神经功能评分及体重变化,HE染色观察CNS病理损伤程度,ELISA法检测外周血IL-4、IL-6、TGF-β、IL-17含量。结果与正常对照组比较,模型组IL-6、IL-17含量升高(P<0.05或P<0.01);IL-4、TGF-β含量降低(P<0.05或P<0.01);泼尼松龙及右归丸组小鼠IL-6、IL-17含量降低(P<0.05或P<0.01);IL-4、TGF-β含量升高(P<0.05或P<0.01)。结论右归丸能够抑制EAE小鼠Th17细胞分化而起到抗感染治疗作用。

EAE大鼠临床病变与胸腺损伤关系探讨

目的:研究EAE大鼠发病后不同时期临床病变与胸腺损伤之间关系。方法:观察正常及EAE发病后3天、5天及恢复期大鼠临床神经功能状态,测量各组大鼠体重、胸腺重量、计算胸腺指数,光镜下观察脑组织及胸腺病理变化,采用流式细胞术检测各组胸腺细胞凋亡率。结果:发病3天及5天大鼠肢体瘫痪,神经功能评分分别为2.60±1.22和1.50±0.512,两组之间无统计学差异。光镜HE染色显示发病3天胸腺显著萎缩,淋巴细胞数减少,发病5天较3天细胞数量有所恢复,恢复期组细胞数明显增多;发病3天脑组织大量炎细胞浸润,发病5天有多数袖套样改变,血管周围围绕较多炎细胞,恢复期炎细胞明显减少。发病3天组胸腺指数较其他组明显下降(P<0.05),其余组胸腺指数相比无统计学意义(P>0.05)。流式细胞术显示发病3天大鼠胸腺细胞凋亡率显著升高(P<0.05),其他组相比无统计学意义(P>0.05)。结论:发病3天大鼠临床神经功能评分及胸腺损伤均较严重,大量胸腺细胞凋亡。随病情发展,胸腺呈现先萎缩、后恢复的动态过程,早于临床症状的恢复,说明胸腺具有自我恢复性,可以促使疾病缓解,可能参与EAE的发病过程。

益肾达络饮对EAE小鼠NgR、Gap-43表达的影响

目的:运用形态学检测技术,探讨益肾达络饮对EAE小鼠中枢神经损伤后神经再生的作用。方法:采用免疫组化方法测定各组小鼠脑组织中NgR、Gap-43的含量,旨在了解NgR在EAE发生后的作用和益肾达络饮对神经再生的作用情况。结果:NgR表达正常组和中药组差异有统计学意义(P<0.05),与其余组差异有极显著统计学意义(P值均<0.01);模型组和激素组、中药组均差异有极显著统计学意义(P值均<0.01);激素组和中药组差异无统计学意义,提示模型组神经再生受抑制程度明显;Gap-43表达在正常组和模型组差异无统计学意义,正常组和激素组、中药组差异有极显著统计学意义(P值均<0.01);模型组和中药组、激素组差异有极显著统计学意义(P值<0.01);激素组和中药组差异有极显著统计学意义(P值<0.01)。结论:益肾达络饮有一定程度促进轴突再生的作用且优于激素组。

火把花根片对EAE大鼠模型VCAM-1和L-选择素的影响

目的探讨火把花根片对实验性自身免疫性脑脊髓炎(EAE)大鼠模型的治疗作用以及对VCAM-1和L-选择素的影响。方法模型组采用豚鼠髓鞘蛋白匀浆和福氏完全佐剂诱发大鼠急性EAE模型;治疗组在模型组基础上予以火把花根(300mg·kg-1·d-1,每日2次),观察动物表现并评分,HE染色和Loyez氏髓鞘染色观察病理和髓鞘改变,免疫组化技术测定脑和脊髓的VCAM-1和L-选择素(L-selectin)水平。结果治疗组未出现临床症状,VCAM-1为(2.13±0.99),L-selectin为(1.88±0.64),与模型组比较差异有统计学意义(P<0.05);脑和脊髓小血管周围炎症细胞浸润明显减少,髓鞘结构完整。结论火把花根片对EAE有治疗作用,其作用机制与抑制VCAM-1及L-selectin表达有关。

火把花根片对EAE大鼠治疗作用及VCAM-1影响的实验研究

目的:探讨火把化根片对实验性自身免疫性脑脊髓炎(EAE)大鼠的治疗作用及VCAM-1的影响。方法:模型组采用豚鼠髓鞘蛋白匀浆和福氏完全佐剂诱发大鼠急性EAE;治疗组在模型组基础上予以火把化根片(600mg.kg-1.d-1,日2次口服),观察临床表现并评分;HE染色和Loyez氏髓鞘染色观察病理和髓鞘改变;免疫组化技术测定脑和脊髓的VCAM-1水平。结果:治疗组未出现临床症状;VCAM-1为(2.13±0.99),与模型组比较P<0.05;脑和脊髓小血管周围炎症细胞浸润明显减少;髓鞘结构完整。结论:火把化根片对EAE有治疗作用,其作用机制与抑制VCAM-1表达有关。

火把花根片对EAE大鼠脑和脊髓L-选择素表达的影响

目的:探讨火把化根片对实验性自身免疫性脑脊髓炎(EAE)大鼠的治疗作用及L-选择素的影响。方法:模型组采用豚鼠髓鞘蛋白匀浆和福氏完全佐剂诱发大鼠急性EAE;治疗组在模型组基础上予以火把化根(600mg.kg-1.d-1)治疗,观察临床表现并评分;HE染色和Loyez氏髓鞘染色观察病理和髓鞘改变;免疫组化技术测定脑和脊髓的L-选择素水平。结果:治疗组未出现临床症状,L-选择素为1.88±0.64,与模型组比较P<0.05;脑和脊髓小血管周围炎症细胞浸润明显减少;髓鞘结构完整。结论:火把化根片对EAE有治疗作用,其机制与抑制L-选择素表达有关。

糖皮质激素受体阻断剂对Wistar大鼠EAE的影响

目的:观察糖皮质激素受体阻断剂(RU486)对EAE大鼠的影响。方法:雌性Wistar大鼠23只分成三组:对照(Control)组、模型(EAE)组、RU486组,采用豚鼠脊髓匀浆/完全弗氏佐剂(GPSCH/CFA)免疫Wistar大鼠建立EAE模型,采用行为学变化观察动物的发病情况,常规HE和Kluver&Barrera染色法观察中枢神经系统(CNS)的病理变化情况。结果:①EAE组7/8大鼠出现典型的EAE行为学改变、CNS炎性细胞浸润(Okuda评分)和髓鞘脱失。②RU486组3/9大鼠出现行为学改变、CNS炎性细胞浸润和髓鞘脱失,均重于模型组(P<0.01)。结论:RU486未增加大鼠EAE的发病率,但可使EAE大鼠的行为学改变、CNS炎性细胞浸润和髓鞘脱失加重。

来氟米特对EAE豚鼠外周血CD28/CTLA-4共刺激分子表达的影响

目的通过观察来氟米特对实验性变态反应性脑脊髓炎(experimental allergic encephalomyelitis,EAE)豚鼠外周血CD28/CTLA-4共刺激分子表达的影响,探讨来氟米特对EAE的防治作用及免疫学机制。方法将50只成年雌性豚鼠随机分为5组,每组各10只,分别为正常对照组、EAE对照组、低剂量、治疗组、中剂量治疗组和高剂量治疗组。低、中、高剂量治疗组于造模前7 d始按体质量分别予来氟米特10、20、40 mg/(kg·d)灌胃,均1次/天,至实验终止。流式细胞术检测各组外周血CD4+T细胞膜上CD28、CTLA-4共刺激分子表达情况并记录豚鼠发病情况。结果高、中剂量治疗组较EAE对照组潜伏期延长、进展期缩短、神经功能障碍评分降低,差异有统计学意义(P<0.05),以高剂量治疗组最明显(P<0.05)。EAE对照组较正常对照组发病高峰期外周血CD4+T细胞膜上CD28分子表达升高(P<0.05),而CTLA-4表达下降(P<0.05);高、中剂量治疗组较EAE对照组CD28分子表达下调(P<0.05),而CTLA-4表达升高(P<0.05);各治疗组间CD28分子的表达以高剂量治疗组下调最显著(P<0.05),CTLA-4分子的表达以高剂量治疗组上调显著(P<0.05)。相关分析显示EAE对照组、各治疗组外周血CD28/CTLA-4比值与神经功能障碍评分均呈正比(r=0.85,P=0.002;r=0.77,P=0.000)。结论来氟米特可减轻EAE豚鼠神经功能缺损症状,且剂量越高效果越好。其作用机制可能是通过下调外周血CD4+T细胞上CD28分子,上调CTLA-4分子的表达,使EAE豚鼠免疫失衡重新达到平衡,从而减轻炎性反应,调节免疫应答,减轻临床症状。

NPY对EAE豚鼠发病及血清IL-4、IFN-γ含量影响的研究

[目的]探讨神经肽Y(NPY)对EAE豚鼠发病潜伏期、神经功能障碍评分及对血清IL-4、IFN-γ含量的影响,研究NPY对EAE发病的保护作用及其可能的免疫调节机制。[方法]将30只豚鼠随机分为正常对照组、EAE对照组、NPY干预组。观察3个组豚鼠血清IL-4、IFN-γ的含量,观察EAE对照组、NPY干预组发病潜伏期、神经功能障碍评分情况。[结果]正常对照组豚鼠未发病,EAE对照组、NPY干预组豚鼠发病后神经功能障碍明显。与EAE对照组相比较,NPY干预组发病潜伏期明显延长(P﹤0.001),发病高峰期神经功能障碍评分明显降低(P﹤0.001),死亡率降低(P﹤0.05),高峰期血清IL-4含量明显增高(P﹤0.001),血清IFN-γ含量明显降低(P﹤0.001)。豚鼠高峰期血清IFN-γ水平与发病潜伏期成负相关,与高峰期神经功能障碍评分成正相关;血清IL-4水平与发病潜伏期成正相关,与高峰期神经功能障碍评分成负相关。[结论]侧脑室注射NPY对EAE能起到保护作用,其保护机制可能是通过促进IL-4分泌,抑制IFN-γ的产生而发挥。