小鼠脾脏注射日本血吸虫卵所诱发肝脾内细胞应答的比较研究

本实验选用Ｃ５７Ｂｌ／６小鼠经脾注入日本血吸虫虫卵，对虫卵所诱发的肝脏和脾脏细胞反应进行了比较研究。观察结果显示在致敏组与非致敏组小鼠脾脏中均未出现以嗜酸性粒细胞为主的虫卵肉芽肿，与肝脏中细胞反应明显不同，且虫卵在脾内诱发的细胞反应也弱。分析认为可能与脾脏内存在针对血吸虫虫卵肉芽肿形成的免疫调节有关，值得进一步探讨，并认为本实验模型将可能有助于进行脾脏免疫应答与肝虫卵肉芽肿形成关系的研究。     

经脾注射日本血吸虫虫卵诱发C57BL／6鼠肝脏细胞反应的初…

为探讨日本血吸虫虫卵肉芽肿形成机理和病理作用，本实验改进Ｂｏｔｒｏｓ方法，设虫卵可溶性抗原（ＳＥＡ）致敏组和未致敏组，选用Ｃ５７ＢＬ／６鼠经脾注射虫诱发小鼠日本血吸虫肝肉芽肿，并对虫卵诱发的细胞反应进行了观察。结果显示：（１）经脾注射虫卵诱发小鼠肝肉芽肿方法简单，安全，有效，所建模型，特别是致敏组模型在肉芽肿形成机理研究中较有价值。（２）ＳＥＡ致敏可加强日本血吸虫肝肉芽肿形成。（２）抗体或抗原抗体     

经脾注射日本血吸虫虫卵诱发C57BL／6鼠肝脏细胞反应的初步探讨

为探讨日本血吸虫虫卵肉芽肿形成机理和病理作用，本实验改进Ｂｏｔｒｏｓ方法，设虫卵可溶性抗原（ＳＥＡ）致敏组和未致敏组，选用Ｃ５７ＢＬ／６鼠经脾注射虫卵诱发小鼠日本血吸虫肝肉芽肿，并对虫卵诱发的细胞反应进行了观察。结果显示：（１）经脾注射虫卵诱发小鼠肝肉芽肿方法简单、安全、有效；所建模型，特别是致敏组模型在肉芽肿形成机理研究中较有价值。（２）ＳＥＡ致敏可加强日本血吸虫肝肉芽肿形成．（３）抗体或抗原－抗体复合物作用参与日本血吸虫肝肉芽肿形成。（４）虫卵及虫卵肉芽肿均对肝细胞具有一定损伤作用。     

小鼠日本血吸虫肝虫卵肉芽肿模型的建立

本文报告应用腹腔注射SEA致敏C57BL/6小鼠,继之经脾脏攻击注射虫卵的方法,建立了小鼠日本血吸虫肝虫卵肉芽肿模型,并与自然感染模型作比较.结果证明,SEA致敏组小鼠肝虫卵肉芽肿发生率为100%.其肉芽肿的形态、细胞组成、转化发展过程及单虫卵肉芽肿的直径和面积均与自然感染模型相似.本实验表明经脾脏注射虫卵及SEA致敏建立小鼠日本血吸虫肝虫卵肉芽肿模型是一种良好的肉芽肿实验动物模型.     

日本血吸虫虫卵肉芽肿内抗原和抗体的动态

用日本血吸虫虫卵注入肺内同步产生肉芽肿的小鼠肺模型进行研究。发现新鲜虫卵注入未致敏小鼠肺内,3.5d即出现细胞反应,28d达高峰,淋巴细胞和巨噬细胞是早期的主要成分。虫卵内抗原(SEA)于注射后第1d最高,随即逐渐下降,卵周抗原3.5d开始逐渐增高,28d达到高峰,其后逐渐减少,未测到抗-SEA抗体。以抗原消耗的虫卵注入致敏小鼠,至第35d实验结束时未见明显肉芽肿形成。结果表明新鲜虫卵能对未致敏小鼠诱发肉芽肿形成;日本血吸虫虫卵肉芽肿形成的机制与曼氏血吸虫者相似,也是虫卵抗原(SEA)诱发的细胞免疫为主的超敏反应。     

日本血吸虫单克隆抗独特型抗体NP30对虫卵肉芽…

应用日本血吸虫单克隆抗独特型抗体ＮＰ３０腹腔注射致敏Ｃ５７ＢＬ／６小鼠，继之经脾脏注射虫卵形成的肝虫卵肉芽肿模型。用ＳＥＡ致敏组作阳性对照，ＳＰ２／０腹水组作阴性对照。实验结果表明，在虫卵攻击后第４ｄ，ＮＰ３０致敏组肝虫卵肉芽肿面积、体积即开始明显增加，出现多量嗜酸性粒细胞浸润。     

小鼠感染日本血吸虫后肝脏内的细胞反应

本文报告C57BL/6小鼠感染日本血吸虫后,随着血吸虫及虫卵的发育,肝脏内产生相应的细胞反应。感染后第七天,肝窦及小叶间静脉周围嗜酸性粒细胞和淋巴细胞开始增加,在28天小叶间静脉周围开始出现浆细胞。提示宿主对童虫-成虫的反应是免疫反应。虫卵发育成熟后,肝窦内嗜酸性粒细胞再次升高,小叶间静脉周围各类细胞继续上升,提示宿主对童虫-成虫的反应与对虫卵的反应是分阶段的。本研究还发现,虫卵一旦发育成熟,肉芽肿迅速形成,推测虫卵成熟前宿主已处于致敏状态,宿主对童虫-成虫的免疫反应可能参与虫卵肉芽肿的形成。     

日本血吸虫单克隆抗独特型抗体NP30对虫卵肉芽肿形成的致敏作用

应用日本血吸虫单克隆抗独特型抗体ＮＰ３０腹腔注射致敏Ｃ５７ＢＬ／６小鼠，继之经脾脏注射虫卵形成的肝虫卵肉芽肿模型。用ＳＥＡ致敏组作阳性对照，ＳＰ２／０腹水组作阴性对照。实验结果表明，在虫卵攻击后第４ｄ，ＮＰ３０致敏组肝虫卵肉芽肿面积、体积即开始明显增加，出现多量嗜酸性粒细胞浸润。肉芽肿面积在第８ｄ、体积在第１５ｄ达高峰值，与ＳＥＡ致敏组的高峰值相近（Ｐ＞０．０５）。而ＳＰ２／０腹水组肉芽肿的面积、体积至第３２ｄ才达高峰值，其高峰值低于ＮＰ３０致敏组（面积Ｐ＜０．０５，体积Ｐ＜０．０１）。本文提示ＮＰ３０对肝虫卵肉芽肿的形成具有致敏作用。     

用日本血吸虫干卵建立体外肉芽肿反应模型

目的在体外建立一种与血吸虫感染宿主组织内病变相似的虫卵肉芽肿反应模型以便对该病变的形成机理作进一步研究。方法将日本血吸虫干卵悬液分别加于感染组、虫卵免疫组和正常对照组小鼠脾细胞培养物中，诱导这些脾细胞对虫卵的附着等反应，对影响反应强度的部分因素进行观察。结果感染组和免疫组的脾细胞反应均显著强于正常对照组者，感染组的反应较免疫组者更早出现且更显著。结论采用日本血吸虫干卵和感染鼠脾细胞在体外建立虫卵肉芽肿反应模型简便可行。     

日本血吸虫虫卵肉芽肿特异性免疫调节的动态观察

控制虫卵肉芽肿病变,可以达到进一步控制血吸虫病发生发展的目的。应用特异性抗原诱导宿主产生免疫耐受,从而使虫卵肉芽肿反应减弱,虽早有研究报道[1～4],但大多应用肺肉芽肿的动物模型进行研究,并且观察周期较短。然而免疫耐受对自然感染宿主肝脏内虫卵肉芽肿反应的影响尚未见报告[5],本研究采用ＳＥＡ诱导新生小鼠产生免疫耐受,观察免疫耐受状态下,小鼠人工感染日本血吸虫后,肝脏中虫卵肉芽肿形成的动态变化。1　材料与方法11　实验动物分组与处理新生(1周龄)杂交小鼠80只由本院实验动物中心提供。随机分为4组。组Ⅰ～Ⅲ的小鼠分别腹腔注…     

吡喹酮治疗对血吸虫感染小鼠免疫病理变化的影响

目的 :阐明吡喹酮治疗对血吸虫感染宿主免疫病理的影响。方法 :应用免疫组织化学和图像分析技术 ,观察日本血吸虫感染小鼠在吡喹酮治疗后肝组织内可溶性虫卵抗原 ( SEA)及抗体水平和虫卵肉芽肿的变化。结果 :治疗后 5wk,与对照组相比 ,治疗组减虫率为 98.3% ,平均肝重量和体积均显著减小 ,治愈小鼠的肝表面结节明显减少 ,组织内沉积的虫卵已钙化 ,部分虫卵肉芽肿已呈纤维疤痕样改变 ,对照组肝内仍可见慢性和少量急性虫卵肉芽肿。治疗组肝组织内抗原水平下降 ,而其抗体水平不受影响 ,肝内虫卵肉芽肿的平均直径和面积均较对照组显著缩小 ( P<0 .0 1)。结论 :吡喹酮治疗可使肝组织内 SEA水平下降 ,从而抑制了虫卵肉芽肿的病变 ,但不能逆转已形成的虫卵肉芽肿病变。     

小鼠急性日本血吸虫病肝脏肉芽肿动态及脾细胞IL-4 mRNA水平的相应变化

本研究观察了小鼠急性日本血吸虫病肝脏肉芽肿的动态改变及在ConA或SEA体外诱导下小鼠脾细胞IL－4mRNA水平的相应变化。实验结果显示SEA刺激下牌细胞IL－4mRNA的动态变化与肝脏内芽肿的形成、发展及调节过程密切相关。在血吸虫成虫排卵前,无论ConA或SEA均不能诱导IL－4mRNA的转录。在感染后5周,肝脏肉芽肿开始出现．此时用RT－PCR法可以检测到IL－4mRNA的特异条带。感染后8周,肉芽肿炎症反应达高峰,SEA诱导的IL-4mRNA转录水平同时增高。感染10周以后,肉芽肿体积逐渐缩小,IL－4mRNA特异条带也同时消失。提示IL-4可能在肉芽肿的形成及调节过程中起重要作用。     

The effect of zinc deficiency on granuloma formation, liver fibrosis, and antibody responses in experimental schistosomiasis.

The influence of various dietary zinc levels on the fibrotic aspects of granuloma formation and on the humoral response to schistosome egg antigens was investigated in C57Bl/6 mice by feeding groups of animals zinc-deficient diets. At six weeks of age, control and zinc-deficient mice were exposed individually to 50-60 cercariae of the Brazilian LE strain of Schistosoma mansoni. The animals were maintained on their respective diets for eight weeks postinfection, then all animals were killed and analyzed for body weight, spleen weight, collagen content of the liver, in vivo granulomatous histopathology, and antibody responses to soluble egg antigens. Zinc-deficient mice experienced stunted growth and reduced weight gain. Granulomatous hypersensitivity to schistosome eggs in the liver was measured in liver histopathologic sections using morphometric analysis and was found to be depressed in infected mice fed the moderately and the severely zinc-deficient diets. The low level of zinc in the diet also affected the humoral immune response of the host to schistosome egg antigens.     

The Schistosoma mansoni egg-derived r38 peptide-induced Th1 response affects the synchronous pulmonary but not the asynchronous hepatic granuloma growth

The p38 peptide derived from Schistosoma mansoni egg‐antigens (SEA) is a preferential inducer of the Th1 response. In the present study, we investigated whether induction of a p38‐specific Th1 or Th2 response can influence granuloma development in infected or sensitized mice. Mice sensitized with SEA/IL‐12 3 weeks after infection but before worm oviposition commenced developed Th1 cytokine responses and had significantly reduced hepatic granuloma size. Similar immunization with p38/IL‐12 induced a strong peptide‐specific Th1, mixed SEA‐specific Th1/Th2 responses without effect on hepatic granuloma development. Presentation of p38 with alum or alum/IL‐12 mixture enhanced Th2 cytokine responses and hepatic granuloma sizes. In the synchronized pulmonary model, sensitization of naïve mice with p38/IL‐12 induced a strong Th1 cytokine production to p38 and SEA, led to a moderate increase in granuloma growth at days 4 and 8 following egg injection and actually promoted the resolution of the lesion by day 16. Sensitization with p38 in alum induced Th2 cytokine production and generated the largest granulomas whereas the p38/alum/IL‐12 sensitized group showed intermediate results in cytokine production and granuloma growth. Thus, in infected mice, the p38 induced strong Th1 response was insufficient to cross‐regulate the evolving Th2 environment that generated large granulomas.     

Soluble egg antigens from Schistosoma mansoni induce angiogenesis-related processes by up-regulating vascular endothelial growth factor in human endothelial cells

Schistosomiasis mansoni is characterized by hepatic granuloma formation. Endothelial cell activation within these granulomas may contribute to their development and to increased vascularization in the granuloma periphery. The earliest event in granuloma formation is the lodging of schistosome eggs within presinusoidal capillaries. The eggs secrete factors that may activate endothelial cells. This study investigated the effects of Schistosoma mansoni soluble egg antigen (SEA) on angiogenic processes: proliferation, tube formation, and apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs require serum and growth factors to proliferate in vitro. Proliferation occurred when SEA or live eggs were substituted for growth factors, but not for serum. SEA increased HUVEC tube formation and decreased HUVEC apoptosis after serum and growth factor deprivation. Messenger RNA for vascular endothelial growth factor (VEGF) increased 2-fold in SEA-treated HUVECs. These findings suggest that products secreted by schistosome eggs may promote angiogenesis within hepatic granulomas by up-regulating endothelial cell VEGF.     

Modulation of Schistosoma japonicum pulmonary egg granulomas with monoclonal antibodies

We have examined the ability of various Schistosoma japonicum egg antigens to sensitize mice for subsequent secondary pulmonary egg granuloma formation. Further, we produced monoclonal antibodies (Mabs) specific for egg antigens and evaluated their abilities to modulate pulmonary granuloma formation and inhibit soluble egg antigen (SEA)-stimulated lymphocyte blastogenesis. A homogeneous, 140 Kd egg glycoprotein, SJe; 140-GP was nearly as effective as intact eggs in sensitizing for egg-focused pulmonary granuloma formation, while SEA, or the heterogeneous immunoaffinity (IA)-purified C10 antigens were ineffective. The in vivo administration of chronic infection serum (CIS) or Mabs reactive with SJe; 140-GP, to egg-sensitized/egg-challenged mice, modulated pulmonary granuloma formation. Two of these modulatory SJe; 140-GP-specific Mabs (1 A1-1 or 14B3-8), an IgG1, and an IgG3, respectively, did not alter the responses of SEA-stimulated lymph node cells from mice with acute or chronic schistosomiasis japonica. In contrast, another SJe; 140-GP-specific IgG3 Mab (7A6-5), CIS, immunoaffinity purified anti-SEA from CIS, or the non-SEA-binding fraction of CIS, all resulted in dose-related inhibition of SEA-induced proliferation. These data confirm the antibody-driven nature of some immunoregulatory networks in murine schistosomiasis japonica, and extend these observations to include certain Mabs. The immunogenic nature of SJe; 140-GP, and the modulatory and inhibitory activities of Mabs specific for this glycoprotein, indicate it may play a central role in granuloma formation and modulation in this infection.