实验性自身免疫性肝炎小鼠的口服耐受诱导研究

口服耐受是一种治疗全身性炎症疾病的潜在手段。在一些动物模型中,口服自身抗原可抑制自身免疫反应。目的:观察在实验性自身免疫性肝炎(EAH)小鼠中诱导口服耐受对肝脏病变的影响。方法:在实验第1天和第7天,将新鲜制备的蛋白质浓度为0.5-2 g/L的肝抗原S-100 0.5 ml和等体积的弗氏完全佐剂(CFA)充分乳化后,予C57BL/6小鼠腹腔注射,以诱导EAH的产生。诱导:EAH前5天起,每天分别予小鼠插管喂饲1 mg和10mg的肝抗原S-100、肝抗原S-100第1峰、第2峰和第3峰,对照组以PBS 1 ml灌胃。结果:仅肝抗原S-100第1峰抗原高剂量组小鼠的肝组织学病变程度较对照组显著减轻(P<0.05),血清丙氨酸转氨酶(ALT)水平也较对照组显著下降(P<0.05)。肝抗原S-100总抗原高剂量组的血清.ALT水平较对照组显著下降(P<0.05),肝组织学病变程度呈下降趋势,但与对照组的差异无显著性。结论:口服肝抗原S-100第1峰抗原可诱导EAH小鼠的免疫耐受。     

自身免疫性肝炎小鼠肝组织神经细胞粘附分子的表达

目的观察实验性自身免疫性肝炎(EAH)肝组织中神经细胞粘附分子(NCAM)的表达,并探讨其表达强度与肝组织学分级的相关性。方法以同种系S-100肝抗原与弗氏完全佐剂充分乳化后于第1和第7天于C57BL/6小鼠腹腔注射诱导EAH模型。分别于首次免疫后第7、14和21天处死小鼠。以免疫组织化学和RT-PCR法研究NCAM表达。结果EAH模型组小鼠肝内NCAM表达逐渐增强,淋巴细胞浸润和肝细胞破坏逐渐加重。强的松龙可改善肝组织学分级,并抑制NCAM的表达。NCAM的表达强度与肝组织学分级呈正相关(r＝0.71,Ｐ＜0.01)。结论NCAM作为移行信号而便于淋巴细胞的肝内浸润,从而诱导肝细胞的损伤。     

辅助性T淋巴细胞22及其效应因子IL-22在自身免疫性肝炎小鼠模型中的表达及意义

目的研究自身免疫性肝炎(AIH)小鼠模型中辅助性T淋巴细胞(Th)22细胞水平及其功能因子IL-22的表达情况,探索其在AIH发病中的意义。方法选取30只4周龄雄性C57BL/6小鼠随机分为对照组(n=6)、AIH组(n=14),剩余10只用于提取肝脏特异性抗原S100。在实验第1天和第7天通过腹腔注射法将新鲜提取的S100与等体积弗氏完全佐剂混合液注射到小鼠腹腔内,第28天成功建立AIH小鼠模型(造模期间AIH组有7只小鼠因注射不当、出现腹水、感染等原因死亡)后,将小鼠经腹腔注射5%水合氯醛(0.1 ml/10 g)麻醉后摘取眼球取血,收集小鼠脾脏采用流式细胞术检测Th22细胞数,RT-PCR检测AHR mRNA水平;收集肝组织用于HE染色观察肝脏病理变化,RT-PCR和免疫印迹法检测肝组织IL-22、IL-22R表达情况;ELISA法检测血清中IL-22细胞因子水平。2组间比较采用t检验。结果对照组小鼠肝组织排列整齐,肝小叶结构清晰,AIH组小鼠汇管区有大量炎症细胞浸润,肝组织出现点状甚至碎片状坏死。AIH组Th22细胞数较对照组明显升高[(0.083±0.052)%vs(1.555±0.812)%,t=-4.405,P0.05]。AIH组小鼠脾脏中Th22转录因子AHR mRNA的相对表达量较对照组有明显升高(0.485±0.096 vs 1.268±0.366,t=-5.452,P0.05)。AIH组肝组织中IL-22 mRNA和IL-22R mRNA的相对表达量均较对照组明显升高(IL-22 mRNA:1.146±0.227 vs 3.813±0.478,t=-12.458,P0.001;IL-22R mRNA:0.276±0.037 vs 1.734±0.248,t=-15.333,P0.001);AIH组肝组织的IL-22及IL-22R的蛋白相对表达量均明显高于对照组(1.040±0.261 vs 0.410±0.077,t=-6.324,P0.05;1.432±0.304 vs 0.830±0.146,t=-6.316,P0.05)。AIH组血清IL-22水平较对照组升高,且差异有统计学意义(t=-15.799,P0.05)。结论 AIH小鼠Th22细胞及IL-22因子的表达水平均明显升高,其可能在AIH的发病中起重要作用。     

商陆抗病毒蛋白在急性人乙型肝炎病毒感染小鼠体内的抑制作用

目的 探讨商陆抗病毒蛋白(PAP)在急性HBV感染小鼠模型体内抗HBV的效果.方法 通过尾静脉注射具有复制能力的HBV真核表达质粒来建立小鼠急性HBV感染模型.根据注射后第1天小鼠血清HBsAg和HBeAg水平,从35只小鼠中选出24只进行配对,分为PAP治疗组(腹腔注射0.25 mg/kg PAP)和对照组.于PAP注射前、注射后第1、3、5、7天,时间分辨免疫荧光分析法检测小鼠血清HBsAg、HBeAg和抗-HBc水平,荧光定量PCR检测小鼠血清HBV DNA水平.注射后第7天HE染色检测肝组织病理变化,免疫组织化学检测肝组织HBsAg、HBeAg表达.采用配对t检验进行统计学分析.结果 与对照组相比,在PAP腹腔注射后第1、3、5天对HBsAg的抑制率分别为23%(t=116.3,P<0.05)、47%(t=38.2,P<0.05)、68%(t=23.7,P<0.05),对HBeAg的抑制率分别为36%(t=34.2,P<0.05)、55%(t=61.6,P<0.05)、83%(t=98.8,P<0.05),对HBV DNA的抑制率分别为70.7%(t=6.6,P<0.05)、86.9%(t=5.9,P<0.05)、95.2%(t=36.6,P<0.05)、95.3%(t=19.7,P<0.05).结论 0.25 mg/kg剂量的PAP在急性HBV感染小鼠模型体内对血清和肝组织的HBsAg、HBeAg的表达及HBV DNA的复制均有明显的抑制效果.     

左氧氟沙星联合CD_(25)单克隆抗体治疗小鼠结核病的初步研究

目的 研究CD_4~+CD_(25)~+调节性T细胞(Treg细胞)消除与左氧氟沙星联合治疗对小鼠结核病细胞免疫作用的影响.方法 3～4周龄C57BL/6雌性小鼠76只,体重17～19 g,随机数字表法分为对照组、CD_(25)单克隆抗体(PC61)消除组、左氧氟沙星组和联合治疗组,每组19只.PC61消除组和联合治疗组小鼠腹腔注射含50 μg PC61的PBS,0.2 ml/只,对照组和左氧氟沙星组小鼠腹腔注射含50μg小鼠IgG同型对照的PBS,0.2ml/只.全部小鼠3 d后尾静脉注射0.1 ml的H_(37)Rv(1×10~6 CFU)造模,左氧氟沙星组和联合治疗组小鼠于攻毒后第2天每只给予左氧氟沙星200 mg·kg~(-1)·d~(-1)连续灌胃45 d.分析小鼠体内不同组织中Treg细胞百分率及其对特异性细胞免疫、肺组织病理变化的影响.应用单因素方差分析对4组连续变量进行检验,组间比较采用q检验,组内不同时间点比较采用t检验.结果 感染MTB第10天和第30天小鼠脾细胞中Treg细胞百分率:对照组分别为(30±4)%和(17.3±1.6)%,PC61消除组分别为(21±4)%和(16.1±1.3)%,左氧氟沙星组分别为(44±6)%和(24.7±2.0)%,联合治疗组分别为(24±3)%和(10.4±1.0)%,除第10天联合治疗组与PC61消除组比较无明显差别外,其他各组间比较均差异有统计学意义(q值为3.62～5.56,均P<0.05).联合治疗组小鼠的肺组织病变较轻,死亡数量较少.结论 Treg细胞消除联合左氧氟沙星治疗可促进结核病小鼠的特异性细胞免疫,使肺内病变有所改善,并可降低小鼠的病死率.     

灭活血吸虫卵预防小鼠实验性结肠炎的实验研究

目的 研究血吸虫卵对小鼠三硝基苯磺酸(TNBS)所致结肠炎的预防作用及其机制.方法 TNBS灌肠诱导小鼠结肠炎模型.60只小鼠均分为对照组(不予任何处理)、干预组及模型组.干预组小鼠于造模前第14天和第3天分别腹腔内注射冰冻灭活的血吸虫卵10000个.模型组小鼠造模前腹腔内注射0.9%氯化钠溶液.造模后第7天处死存活小鼠,统计小鼠死亡率.观察结肠形态和病理特征.实时PCR法测定结肠组织中干扰素(IFN)-γ及白细胞介素(IL)-10 mRNA表达.ELISA法测定血清中IFN-γ及IL-10活性.结果 干预组小鼠死亡率较模型组显著下降(20%比50%,P＜0.05),结肠组织炎性反应显著减轻(Ameho-criteria评分:1.58±0.5比4.18±0.8,P＜0.05),结肠组织及血清中IFN-γ活性显著下降[血清:(29.79±6.97)pg/ml比(48.33±16.59)pg/ml,结肠:(2.31±1.08比7.23±3.52)P＜0.053、IL-10活性显著升高[血清:(38.22±9.96)pg/ml比(28.87±5.74)pg/ml,结肠:7.44±3.04比3.68±1.58 P＜0.05].结论 腹腔内注射血吸虫卵能减轻TNBS所致小鼠实验性结肠炎肠道炎性反应,可能与血吸虫卵提高结肠组织和血清中IL-10活性、降低INF-γ活性有关.     

砒石对支气管哮喘小鼠T淋巴细胞周期及Bcl-2基因表达的影响

为观察砒石对过敏性支气管哮喘(简称哮喘)小鼠体内T淋巴细胞周期和Bcl 2基因表达的影响,我们探讨了砒石治疗哮喘的机制。材料与方法　5周龄昆明种雄性小鼠4 9只,体重(2 0±2 )g ,购自广东医学院实验动物中心。将4 9只小鼠按随机分配法分为7组。(1)对照组(A组) 7只:第1、7、14天给予生理盐水0 5ml腹腔注射,第2 1天开始用生理盐水雾化吸入,每天1次,每次1h ,连续5d ,每天雾化吸入前0 5h用生理盐水(10ml/kg)灌胃;(2 )哮喘模型组(B组) 7只:第1、7、14天给予卵蛋白(OVA) 15 μg和氢氧化铝凝胶2mg ,用生理盐水稀释至0 5ml腹腔注射,第2 1天开…     

NOD/Lt小鼠腹腔注射1,25-(OH)2D3诱发免疫耐受的机制

目的　探讨1, 25 (OH)2D3 阻断NOD/Lt小鼠发生1型糖尿病的免疫机制。方法　60只4周龄NOD/Lt小鼠(25g)分为2组,组1隔天腹腔注射1, 25 (OH)2D3 (5μg/kg),组2腹腔注射花生油作为对照。所有小鼠在第1天和第15天腹腔注射环磷酰胺以加速糖尿病的发生,第30天处死并观察。免疫组化检测Bcl 2,Bax在胰岛和T淋巴细胞的表达;流式细胞仪检测T淋巴细胞亚群分布及凋亡率;RT PCR检测Th1 /Th2 亚群的漂移。结果　1, 25 (OH)2D3 处理组糖尿病发病率下降,脾T淋巴细胞凋亡率增加〔(55. 8±5. 4)% vs(28. 9±3. 6)%,P<0. 05〕;CD4 Th2 亚群增加(IL 4和IL 10mRNA显著增加, P<0. 01)。结论　1, 25 (OH)2D3 通过加速T淋巴细胞的凋亡以减轻细胞免疫反应并最终延缓胰岛β细胞的凋亡,并使CD4 Th1 亚群向CD4 Th2 亚群漂移,导致NOL/Lt小鼠1型糖尿病发病率下降。     

1,6-二磷酸果糖对病毒性心肌炎小鼠心肌烟酰胺腺嘌呤二核苷酸磷酸氧化酶p22phox亚基蛋白表达的影响

目的 观察1,6-二磷酸果糖(FDP)对病毒性心肌炎小鼠心肌还原型烟酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶p22phox亚基蛋白表达的影响,探讨FDP对病毒性心肌炎的保护作用.方法 4周龄雌性BALB/c小鼠30只,体质量(12±2)g.按体质量将小鼠随机分为病毒组和治疗组,每组15只.两组小鼠同时1次性腹腔注射柯萨奇B3病毒(CVB3) 0.1 ml,治疗组在注射CVB3后的第1天,每日腹腔注射1次FDP,连续注射7d,注射剂量为300 mg/kg.在注射结束后的第4、8、21天,两组分别各处死5只小鼠,取心脏做心肌病理检查,Western免疫印迹法检测病毒性心肌炎小鼠心肌细胞内NADPH氧化酶p22phox亚基蛋白表达,图像分析系统测量p22phox亚基蛋白阳性表达区域平均吸光度(A)值,并进行定量分析.结果 感染后第4天,光镜下病毒组小鼠心肌间可见少量炎症细胞浸润,心肌细胞肿胀;治疗组小鼠心肌间仅有少量炎性细胞浸润.感染后第8天,病毒组小鼠心肌出现坏死性崩解,大量炎症细胞浸润;治疗组小鼠心肌间可见稀疏的散在炎性细胞浸润.感染后第21天,病毒组小鼠心肌坏死灶中有慢性炎症细胞浸润,出现结缔组织增生;治疗组小鼠心肌可见少量慢性炎症细胞浸润.病毒组在第8天炎症浸润最严重.在病毒感染后第4、8、21天,治疗组心肌病变积分[(0.88±0.23)、(2.20±0.24)、(1.56±0.17)分]低于病毒组[(1.32±0.12)、(3.0±0.25)、(2.04±0.17)分,t值分别为3.793、5.1645、4.457,P均＜0.01].Western免疫印迹法分析结果显示,在病毒感染后第4、8、21天,治疗组NADPH氧化酶p22phox亚基蛋白表达(0.776±0.017、0.751±0.018、0.689±0.034)明显低于病毒组(1.052±0.015、0.952±0.019、0.907±0.025,t值分别为3.391、6.716、2.750,P均＜0.01或＜0.05).结论 FDP能下调NADPH氧化酶p22phox亚基蛋白表达,FDP可能通过改变NADPH酶的表达对心肌发挥保护性作用.     

Growth hormone accelerates immune recovery following allogeneic T-cell-depleted bone marrow transplantation in mice

OBJECTIVE: To test in a murine model whether recombinant human growth hormone can promote immune recovery after allogeneic T-cell-depleted bone marrow transplantation. MATERIALS AND METHODS: Lethally irradiated (8.5 Gy) BALB/c mice (H2(d)) were transplanted with 5 x 10(6) T cell-depleted bone marrow cells from C57BL/6 mice (H2(b)). Recipient mice were injected intraperitoneally with recombinant human growth hormone (20 microg/dose/day) or saline for the first 4 weeks after transplantation. These animals were followed for phenotypic and functional immune recovery. RESULTS: Administration of human recombinant growth hormone improved the CD4(+) T-cell counts in peripheral blood on day +14 (44+/-14 vs 33+/-7/microL blood, p<0.05) and day +21 (281+/-109 vs 187+/-76/microL blood, p<0.01) compared with the saline control. These differences were no longer significant by day +28 despite continued growth hormone administration. Similar effects were also observed on CD8(+) T cells and B220(+) B cells. The improvements in peripheral T-cell counts were at least partially as a result of enhanced thymopoiesis because there was an increase in total thymocytes after treatment with growth hormone. T-cell-depleted bone marrow recipients treated with growth hormone rejected the third-party grafts faster than those treated with saline control (median survival time: 20 days vs 26 days, p<0.05). CONCLUSIONS: These data demonstrated that recombinant human growth hormone can accelerate phenotypic and functional immune reconstitution following allogeneic T-cell-depleted bone marrow transplantation in mice.     

糖尿病小鼠缺血诱导的骨髓内皮祖细胞动员障碍

目的 观察糖尿病动物缺血诱导的骨髓内皮祖细胞（EPC）动员是否存在障碍,以及这种障碍是否和缺血诱导的血管内皮生长因子（VEGF）释放降低有关。方法 链脲霉素40mg／kg诱导C5781／6雄鼠糖尿病,非糖尿病组给予等量缓冲液。饲养2个月后,进行左侧股动脉高位结扎离断术造成后肢缺血模型,通过红四氮唑染色法与后肢血管造影确定造模成功。于术前及术后不同时间点采血（1天,3天,n：8;5天,7天及14天,n=5）,三色流式细胞术检测两组动物外周血单个核细胞中c-Ki^＋／Sea-1^＋／flk-1^＋早期EPC比例。ELISA法测定相应时间点血浆VEGF水平。结果 基础状态下,糖尿病组循环EPC数量较非糖尿病组明显减少[（0．60±0．03）％比（0．95±0．09）％,P〈0．001],血浆VEGF水平低于试剂盒检测灵敏度。两组动物缺血诱导的骨髓早期EPC释放曲线相似,即术后1天显著增加,术后3天达峰,动员持续至2周以上。但是在EPC早期快速动员阶段（术后前3天）,糖尿病组外周血早期EPC数量较非糖尿病组明显减少[1天,（1．16±0．29）％比（1．80±0．32）％,P〈0．05;3天,（1．38±0．34）％比（2．37±0．52）％,P〈0．05]。同时组织缺血也伴随着血浆VEGF浓度的显著增高：非糖尿病组血浆VEGF水平在术后一天快速增加并达到峰值,此后渐降至相对较低水平持续两周以上;而糖尿病组术后1天血浆VEGF快速释放明显降低[（73．1±18．6）pg／ml比（128．5±44．2）Pg／ml,P〈0．05]。结论 糖尿病动物基础状态下外周血早期EPC数量减少,组织缺血诱导的骨髓EPC动员障碍,这种障碍可能与缺血诱导的VEGF释放减少有关。     

Protection against hepatic ischemia/reperfusion injury via downregulation of toll-like receptor 2 expression by inhibition of Kupffer cell function

AIM: To elucidate the mechanism of liver protection by inhibition of Kupffer cells (KCs) function. METHODS: All the animals were randomly divided into three groups. Blockade group (gadolinium chloride solution (GdCl3) injection plus ischemia/reperfusion (I/R) injury): GdCl3 solution was injected once every 24 h for 2 d via the tail vein before I/R injury. Non-blockade group (saline solution injection plus I/R injury): saline instead of GdCl3 as a control was injected as in the blockade group. Sham group: saline was injected without I/R injury. Liver samples were collected 4 h after blood inflow restoration. The blockade of the function of KCs was verified by immunostaining with an anti-CD68 mAb. Toll-like receptor 2 (TLR2) was immunostained with a goat antimouse polyclonal anti-TLR2 antibody. Membrane proteins were extracted from the liver samples and TLR2 protein was analyzed by Western blot. Portal vein serum and plasma were taken respectively at the same time point for further detection of the levels of tumor necrosis factor-α (TNF-α) and alanine aminotransferase (ALT), an indicator of liver function. RESULTS: Compared to non-blockade group, CD68+ cells significantly reduced in blockade group (OPTDI, optical density integral): 32.97±10.55 vs 185.65±21.88, P<0.01) and the liver function impairment was relieved partially (level of ALT: 435.89±178.37 U/L vs 890.21±272.91 U/L, P<0.01).The expression of TLR2 protein in blockade group significantly decreased compared to that in non-blockade group (method of immunohistochemistry, OPDTI: 75.74±17.44 vs 170.58±25.14, P<0.01; method of Western blot, A value: 125.89±15.49 vs 433.91±35.53, P<0.01). The latter correlated with the variation of CD68 staining (r= 0.745, P<0.05). Also the level of portal vein TNF-a decreased in blockade group compared to that in non-blockade group (84.45±14.73 ng/L vs 112.32±17.56 ng/L, P<0.05), but was still higher than that in sham group (84.45±14.73 ng/L vs 6.07±5.33 ng/L, P<0.01). CONCLUSION: Inhibition of the function of KCs may protect liver against I/R injury via downregulation of the expression of TLR2.     

Study on hepatoprotective effect of peptide S-8300 from shark liver

AIM: To explore the effects of peptide S-8300 from shark liver (S-8300) on liver function as well as in regulating immune functions in experimental injury models. METHODS: Mice were administered with different doses of S-8300 for four consecutive days, followed by mice injected with tetrachloromethane (CCI4) on d 3. The activity of ALT, AST, LDH, SOD and contents of MDA and GSH in the mice liver were tested. And mice were treated with Cy (100 mg/kg) at the beginning of the experiment to induce immunosuppression model. The S-8300 groups were treated with S-8300 seven days after the beginning of Cy administration. The effects of S-8300 on the formulation of serum hemolysin and the content of IL-2 in serum in the immunosuppression mice were observed. RESULTS: S-8300 obviously decreased the level of ALT (52.2±11.0 U/dL vs135.9±6.5 U/dL, P<0.01), AST (67.5±6.9 U/dL vs 238.8±8.7 U/dL, P<0.01), LDH (155.1±46.8 U/dL vs 240.4±6.0 U/dL, P<0.01) & MDA (0.64?.027 nmol/mg vs 1.06±0.040 nmol/mg, P<0.01) and increased SOD (24.51±1.01 U/mg vs 19.05±0.73 U/mg, P<0.01) & GSH (24.17±0.91 μg/mg vs 14.93±0.45 μg/mg, P<0,01) in mice liver damaged by CCI4. S-8300 also markedly improved the formulation of serum hemolysin (0.094±0.005 A540 vs 0.063±0.006 A540, P<0.01) and increased the level of IL-2 (9.74±1.16 pg/mL vs 5.81±0.87 pg/mL, P<0.01) in serum of the immunosuppression mice. CONCLUSION: The results suggested S-8300 has significant hepatoprotective, immunomodulatory and inhibiting of lipid peroxidation activity.     

Leptin administration exacerbates thioacetamide-induced liver fibrosis in mice

AIM: To investigate the effects of leptin administration on liver fibrosis induced by thioacetamide (TAA). METHODS: Twenty-four male C57Bl/6 mice were randomly allocated into four groups, which were intra-peritoneally given saline (2 mL/kg), leptin (1 mg/kg), TAA (200 mg/kg), TAA (200 mg/kg) plus leptin (1 mg/kg) respectively, thrice a week. All mice were killed after 4 wk. The changes in biochemical markers, such as the levels of alanine aminot-ransferase (ALT) and aspartate aminotransferase (AST) in serum and superoxide dismutase (SOD), malondialdehyde (MDA) in liver were determined. For histological analysis, liver tissues were fixed with 10% buffered formalin, embedded with paraffin. Hematoxylin-eosin (HE) staining and picric acid-Sirius red dyeing were performed. The level of α1(I) procollagen mRNA in liver tissues was analyzed by RT-PCR. RESULTS: Apparent liver fibrosis was found in TAA group and TAA plus leptin group. Compared to saline group, the levels of ALT and AST in serum and MDA in liver increased in TAA group (205.67±27.69 U/L vs50.67±10.46 U/L, 177.50±23.65 U/L vs 76.33±12.27 U/L, 2.60±0.18 nmol/mg pro vs 1.91±0.14 nmol/mg pro, P<0.01) and in TAA plus leptin group (256.17±22.50 U/L vs 50.67±10.46 U/L, 234.17±27.37 U/L vs 76.33±12.27 U/L, 2.97±0.19 nmol/mg pro vs 1.91±0.14 nmol/mg pro,P<0.01). The level of SOD in livers decreased (51.80±8.36 U/mg pro vs 81.52±11.40 U/mg pro, 35.78±6.11 U/mg pro vs 81.52± 11.40 U/mg pro, P<0.01) and the level of α1(I) procollagen mRNA in liver tissues also increased (0.28±0.04 vs 0.11± 0.02, 0.54±0.07 vs 0.11±0.02, P<0.01). But no significant changes were found in leptin group and saline group. Compared to TAA group, ALT, AST, MDA, and α1(I) procollagen mRNA and grade of liver fibrosis in TAA plus leptin group increased (256.17±22.50 U/L vs 205.67± 27.69 U/L, P<0.05; 234.17±27.37 U/L vs 177.50±23.65 U/L, P<0.05; 2.97±0.19 nmol/mg pro vs 2.60±0.18 nmol/mg pro,P<0.05; 0.54±0.07 vs 0.28±0.04, P<0.01; 3.17 vs 2.00, P<0.05), and the level of SOD in liver decreased (35.78±6.11 U/mg pro vs 51.80±8.36 U/mg pro, P<0.05). There were similar changes in the degree of type I collagen deposition confirmed by picric acid-Sirius red dyeing. CONCLUSION: Leptin can exacerbate the degree of TAA-induced liver fibrosis in mice. Leptin may be an important factor in the development of liver fibrosis.     

趋化因子CXC受体3在博莱霉素诱导的肺纤维化中的作用

目的　采用趋化因子受体即CXCR3基因敲除小鼠 ,探讨CXCR3在博莱霉素诱导的肺损伤及纤维化中的作用。方法　采用基因打靶技术得到无CXCR3基因小鼠 6 2只 ,同时选择性别、年龄和体重配对的野生型小鼠 4 8只 ,随机分入不同的实验组及对照组。大鼠气管内注入博莱霉素0 0 2 5U。实验动物按要求处死后 ,取无血的肺组织切片 ,经 10 %甲醛固定后 ,用苏木精 伊红 (HE)和Massontrichrome染色 ,分别观察实验动物肺炎症和纤维化的程度 ;用浓盐酸消化肺组织提取羟脯氨酸并定量来表示肺胶原的含量 ;用磷酸盐缓冲液 (PBS)灌洗肺组织 ,酶联免疫吸附 (ELISA)法测定灌洗液中肿瘤坏死因子α(TNF α)、白细胞介素 5 (IL 5 )及转化生长因子 β(TGF β)的浓度 ;用流式细胞仪检测T细胞亚群。结果　气管内注入博莱霉素后 14d ,CXCR3基因敲除小鼠肺组织炎症程度及纤维化程度较野生型小鼠明显减轻。肺组织炎症程度评分和羟脯氨酸含量 (左肺 )在CXCR3基因敲除小鼠分别为 3 92± 0 37和 (6 7 0± 2 4 2 ) μg ,在野生型小鼠则分别为 5 33± 0 34和 (2 11 5± 2 4 2 )μg ,两组比较差异有统计学意义 (P分别 <0 0 5 ,<0 0 1) ;TGF β水平在CXCR3基因敲除小鼠为(2 2 11± 2 89) μg/L ,在野生型小鼠为 (5 388± 10 71) μg/L ,     

Toll样受体参与小鼠肝脏缺血再灌注损伤

目的探讨Toll样受体是否参与小鼠肝脏缺血再灌注损伤及其机制. 方法用Toll样受体缺损小鼠(C3H/Hej,Hej组)和野生型(C3H/Heouj,Heouj组)小鼠复制部分肝脏缺血再灌注损伤模型,于缺血45min,再灌注1h和3h处死动物,检测血清天门冬氨酸氨基转移酶(AST)和血清肿瘤坏死因子α(TNFα)的含量;并以northern blot及髓过氧化物酶(MPO)试验分别检测缺血肝组织TNFα mRNA的表达和MPO的含量. 结果 (1)再灌注1、3h,与假手术组相比,小鼠血浆AST明显升高,但Hej组明显低于Heouj组(661.83U/L±106.09U/L和1215.5U/L±174.03U/L,t＝-6.65,P<0.01;1145.17U/L±132.43U/L和2958.17U/L±186.81U/L,t＝-5.57,P<0.01);(2)再灌注3h时,与假手术组相比,Hej组和Heouj组小鼠血清TNFα浓度明显升高,且前者明显低于后者(152.39pg/ml±43.3pg/ml和249.12pg/ml±51.89pg/ml,t＝-3.13,P<0.05);(3)再灌注1h,除假手术组外,Hej组和Heouj组小鼠缺血肝组织内可见TNFα mRNA的表达,但前者的表达水平明显低于后者,杂交带密度分析显示两者之间差异有显著性 (80.3±28.8与189.4±24.6,t＝-3.25,P<0.05);(4)再灌注3h,与假手术组相比,Hej组和Heouj组小鼠缺血肝组织内MPO含量明显升高,且前者含量明显低于后者(0.059±0.004和0.173±0.025,F＝33.49,P<0.01). 结论 Toll样受体可能通过其介导的炎性通路参与了小鼠肝脏缺血再灌注损伤.     

An effective vaccine against colon cancer in mice： Use of recombinant adenovirus interleukin-12 transduced dendritic cells

AIM： To investigate the effect of a vaccine with recombinant adenovirus interleukin-12 （AdVIL-12） transduced dendritic cells （DCs） against colon cancer in mice. METHODS： DCs and AdVIL-12 were incubated together at different time intervals and at different doses. Supernatant was collected and tested for IL-12 by enzyme-linked immunosorbent assay （ELISA）. In order to determine whether tumor cell lysate-pulsed （TP） AdVIL-12/DCs enhance therapeutic potential in the established tumor model, CT26 colon tumor cells were implanted subcutaneously （s.c.） in the midflank of naive BALB/c mice. Tumor-bearing mice were injected with a vaccination of CT26 TP AdVIL-12/DCs on d 3 and 10. As a protective colon tumor model, naive BALB/c mice were immunized s.c. in their abdomens with CT26 TP AdVIL-12/DCs twice at seven day intervals. After the immunization on d 7, the mice were challenged with a lethal dose of CT26 tumor cells and survival times were evaluated. Subsequently, cytotoxic T lymphocyte （CTL） activity and interferon gamma （IFNy） secretion was evaluated in the immunized mice, and assayed CTL ex vivo. RESULTS： Murine DCs were retrovirally transduced with AdVIL-12 efficiency, and the AdVIL-12 transduced DCs secreted a high level of IL-12 （AdVIL-12/DCs, 615.27 ± 42.3 pg/mL vs DCs, 46.32 ± 7.29 pg/mL, P 〈 0.05）. Vaccination with CT26 TP AdVIL-12/DCs could enhance anti-tumor immunity against CT26 colon tumor in murine therapeutic models （tumor volume on d 19：CT26 TP AdVIL-12/DCs 107 ± 42 mm^3 vs CT26 TP DCs 383± 65 mm^3, P 〈 0.05） and protective models. Moreover, the CT26 TP AdVIL-12/DC vaccination enhances tumor-specific CTL activity, producing high levels of IFN7 in immunized mice. Ex vivo primed T cells with AdVIL-12/DCs were able to induce more effective CTL activity than in primed T cells with CT26 TP/DCs （E：T = 100：1, 69.49% ± 6.11% specific lysis vs 37.44% ＋ 4.32% specific lysis, P 〈 0.05）.CONCLUSION： Vaccination with recombinant AdVIL-12 transduced DC p     

Targeting hepatitis B virus antigens to dendritic cells by heat shock protein to improve DNA vaccine potency

AIM： To investigate a novel DNA vaccination based upon expression of the HBV e antigen fused to a heat shock protein （HSP） as a strategy to enhance DNA vaccine potency.
METHODS： A pCMV-HBeAg-HSP DNA vaccine and a control DNA vaccine were generated. Mice were immunized with these different construct. Immune responses were measured 2 wk after a second immunization by a T cell response assay, CTL cytotoxicity assay, and an antibody assay in C57BL/6 and BALB/c mice. CT26-HBeAg tumor cell challenge test in vivo was Performed in BALB/c mice to monitor anti-tumor immune responses.
RESULTS： In the mice immunized with pCMV-HBe-HSP DNA, superior CTL activity to target HBV-positive target cells was observed in comparison with mice immunized with pCMV-HBeAg （44% ± 5% vs 30% ± 6% in E： T 〉 50：1, P 〈 0,05）, ELISPOT assays showed a stronger T-cell response from mice immunized with pCMV-HBe- HSP than that from pCMV-HBeAg immunized animals when stimulated either with MHC class I or class Ⅱ epitopes derived from HBeAg （74% ± 9% vs 31% ± 6%, P 〈 0.01）. ELISA assays revealed an enhanced HBeAg antibody response from mice immunized with pCMV- HBe-HSP than from those immunized with pCMV-HBeAg. The lowest tumor incidence and the slowest tumor growth were observed in mice immunized with pCMV- HBe-HSP when challenged with CT26-HBeAg.
CONCLUSION： The results of this study demonstrate a broad enhancement of antigen-specific CD4^＋ helper,CD8^＋ cytotoxic T-cell, and B-cell responses by a novel DNA vaccination strategy. They also proved a stronger antigen-specific immune memory, which may be superior to currently described HBV DNA vaccination strategies for the treatment of chronic HBV infection.