旋毛虫成虫感染小白鼠的实验研究

本文首次采用旋毛虫成虫感染小白鼠。实验结果表明,小白鼠经旋毛虫成虫感染后,在其肠道内发现旋毛虫成虫,在其肌肉内发现旋毛虫成虫。在其肌肉内发现旋毛虫幼虫。肠道内成虫数量范围在2～25条间。肌肉内幼虫主要分布于膈肌、后腿肌和前腿肌。隔肌内幼虫数量范围2～53条,后腿肌内幼虫和前腿幼虫分布较少,后腿肌内幼虫范围在1～7条,前腿肌内幼虫数量范围在2条。我们认为,旋毛虫成虫在某种条件下,在宿主移换过程中可以起感染期作用而感染宿主,引起宿主旋毛虫感染。     

旋毛虫肌肉囊包内幼虫数量和囊包形态演化的观察

旋毛虫是一种人兽共患的寄生虫病，我国普遍存在，黑龙江省是重要流行区。旋毛虫成虫寄生于宿主的消化系统，幼虫寄生于肌肉系统，可导致包括人体在内的多种哺乳动物宿主感染旋毛虫病。一般认为，肌肉内囊包幼虫数目1～2条，多则6～7条，肌肉内幼虫囊包沿肌纤维平行走行呈梭形。     

旋毛虫肌肉期幼虫分泌排泄物中46-58KD抗原的保护性免疫作用

目的研究旋毛虫肌肉期幼虫分泌排泄物(TsL1-ES)中46-58KD抗原诱发小鼠的保护性免疫能力。方法用该纯化抗原组分加福氏完全佐剂(FCA)腹腔注射免疫昆明小鼠3次,继以旋毛虫感染性幼虫300条攻击感染,感染后第7天计数小鼠肠道成虫数,第30天肌肉幼虫数和血清抗体IgG滴度。结果46-58KD抗原免疫鼠的肠道成虫减虫率、肌肉幼虫减虫率和血清抗体IgG的几何平均倒数滴度(GMRT)分别为46·4%、46·1%和2841·2,与TsL1-ES诱导的保护性免疫力(48·3%、50·2%和3458·6)水平接近,显著高于佐剂对照组(4·8%、8·2%和748·6)。结论TsL1-ES中46-58KD抗原组分可产生明显的保护性免疫作用。     

香肠腌制法对旋毛虫感染性影响的实验研究

目的观察香肠腌制法对旋毛虫肌幼虫感染性的影响。方法30只昆明小鼠被随机分为对照组和实验组,实验组又分5组,共6组,每组5只。对照组每鼠经口感染300条收集的肌幼虫。实验组分5组,4℃,阳性鼠肉香肠配料分别腌制24、48、72、96、120h,然后将5组小鼠每鼠经口感染300条处理好的肌幼虫。感染后28d处死小鼠,取膈肌压片镜检,并将全部肌肉人工消化后计数幼虫数。结果24h组、48h组、72h组、96h组压片法和人工消化法镜检,感染小鼠的幼虫检出率均为100％;4组的幼虫均数均显著低于对照组（P〈0．01）;48h组、72h组、96h组的幼虫均数均显著低于24h组（P〈0．01）。120h组两种方法镜检,感染小鼠均未检出幼虫。结论使用香肠腌制法腌制肉类,随着腌制时间的延长,肉内旋毛虫幼虫的活性和感染性逐渐下降。     

丙硫咪唑驱蛲虫成虫和杀虫卵作用的观察

丙硫咪唑经临床应用证明抗蛲虫效果较佳。为确切了解该药驱成虫和杀虫卵作用,我们选择蛲虫病人实验,现报告结果如下。 1 对象和方法:选择10名4～7岁儿童蛲虫感染者,投200～400mg丙硫咪唑,一次顿服。治疗后1～4天分别以水洗粪便淘虫计数确定驱成虫作用,以透明胶纸粘取儿童肛周虫卵,行人工消化液孵化,24h内观察幼虫的孵出确定杀虫卵作用。 2 结果与讨论:①驱成虫作用:治疗后第一天,收集7名儿童粪便,平均获得成虫1.4条,最多3条,最少0条。总计10条。治疗后第二天,收集6名儿童粪便,平均     

大蒜汁对旋毛虫幼虫杀灭效果研究

目的通过比较经不同浓度大蒜汁浸泡含旋毛虫肌幼虫的肉块对小鼠感染力的影响,来评估大蒜汁对旋毛虫幼虫的杀灭效果。方法 30只昆明小鼠分为5组,喂食经不同浓度的大蒜汁(浓度分别为100.00%、50.00%、25.00%、12.50%)和生理盐水浸泡半小时含有旋毛虫肌幼虫的肉,饲喂30d后剖杀小鼠,观察和计数肌幼虫数。结果小鼠饲喂经100.00%、50.00%、25.00%、12.50%浓度大蒜汁和生理盐水浸泡半小时含有旋毛虫肌幼虫的肉后,在单位肌肉中检出旋毛虫肌幼虫数为0条、10条、60条、140条和235条。结论含旋毛虫肌幼虫的肉经一定浓度的大蒜汁浸泡后其旋毛虫肌幼虫的感染力会降低。     

猪蛔虫乳酸脱氢酶同功酶的电泳研究

寄生蠕虫乳酸脱氢酶的性质和种类数量尚不清楚。Nagase(1968)曾报道猪蛔虫体液的孔酸脱氢酸由2条带组成,而肌肉和卵巢只显示单一带。Langer和Smith(1971)的研究结果表明猪蛔虫全虫提取物中含四种乳酸脱氢酶同功酶,无显著的性别差异。本实验以聚丙烯酰胺凝胶电泳分析猪蛔中乳酸脱氢酶。实验所用猪蛔虫成虫取自高知县屠宰场内自然感染猪蛔虫的猪肠内。取得的成虫以0.85％生理盐水清洗,清洗后放     

斯氏线虫对黄曲条跳甲的侵染能力

本文应用Hassell-Varley模型和Holling功能反应模型对斯氏线虫与黄条跳甲三龄幼虫的关系进行了拟合，得到在48h内，每百条线虫可感染1．4头寄主，线虫间干扰作用为0．2738；每2500条线虫对寄主的瞬时发现率为0．5，在最适宜的条件下，最多可感染72头寄主。线虫对不同龄期的黄曲条跳甲幼虫感染，结果表明，随寄主龄期的增加而感染率增加。     

寄生虫学讲座(8) 旋毛形线虫(旋毛虫)

旋毛虫成虫寄生在人体小肠,幼虫主要寄生在人体的肌肉内。本虫所致的旋毛虫病对人体危害很大,严重感染能致人死亡。1 形态1.1 成虫:虫体细小线状,前端较后端细,咽管结构特殊,长度约占虫体1/3,后段咽管的背侧面为单层的杆     

日本血吸虫脂肪酸结合蛋白DNA联合白细胞介素-12的免疫保护作用

目的探讨白细胞介素-12(IL-12)对日本血吸虫脂肪酸结合蛋白(Sj14FABP)DNA疫苗的辅佐作用。方法大量制备pVIVO2、pVIVO2 IL-12、pVIVO2-Sj14FABP质粒DNA。48只雄性Balb/c小鼠随机分为A、B、C、D组，每组各12只，每只小鼠于免疫前1 d在右后腿股四头肌肌内注射075%盐酸布比卡因30 μL。A组给予0.9%氯化钠注射液100 μL，im；B组给予pVIVO2质粒DNA 100 μg，im； C组给予pVIVO2-Sj14FABP质粒DNA 100 μg，im；D组给予pVIVO2-Sj14FABP质粒DNA 50 μg 和pVIVO2-IL-12质粒DNA 50 μg，im。免疫30 d后，每只小鼠以(40±2)条尾蚴感染，感染45 d后，计数成虫及肝内虫卵；用ELISA法检测小鼠血清中IgG抗体水平。结果C、D组的减虫率分别为24.11%和38.83%,减卵率为27.20%和40.27%，差异有显著性（P＜0.05）；免疫30 d后小鼠血清IgG水平无明显升高，各组间差异无显著性 (P＞005)。结论pVIVO2-Sj14FABP能够诱导小鼠产生部分抗血吸虫感染的保护力，IL-12是一种有效的血吸虫病DNA疫苗佐剂。     

Response of ADA and its isoenzymes in mice infected by Trichinella spiralis and treated with mimosine

Infections caused by the nematode Trichinella spiralis (T. spiralis) are characterized by an inflammatory response in the host. The aim of this study was to identify and evaluate markers for monitoring mice infected with T. spiralis and treated with or without mimosine. The markers that have been used were total and differential white blood cell counts, subpopulations of lymphocytes, serum tADA and its isoenzymes ADA1 and ADA2 activity. The study included 3 groups of BALB/c mice. Group A consisted of 16 healthy mice, Group B of 16 mice infected with T. spiralis and treated with saline, and Group C of 16 mice infected with T. spiralis and treated with mimosine. The measurements were made once per week for the first six weeks continuously following the infection. According to our results, leukocytosis, lymphocytosis and increased percentages of adhesion molecules and CD4 lymphocytes were present in groups B and C one week post-infection. Total ADA activity as well as ADA1 and ADA2 was higher in groups B and C versus group A from the first week post-infection. The levels of tADA activity, ADA1 and ADA2 were higher in group B compared to those of group C and the difference was statistically significant (p<0.05) during the 4th week post-infection. The majority of tADA activity, essential for an efficient immune response, was derived from ADA1 which may have been produced by infected tissues. The elevated activities of tADA and ADA1 may be sensitive markers for infection of T. spiralis and for monitoring the course of the infection.     

Microarray analysis of NF-kappaB signaling pathways in PBMC of mice infected by Trichinella spiralis

The NF-kappaΒ pathway gene expression profiles were compared between 10, 20 and 39 days after Trichinella spiralis experimental infection in BALB/c mice. Out of 128 genes, 19 (14.8%) genes were present in non-infected and post-infected mice. The expression of 7 (36.8%) genes was downregulated 10 and 20 days post-infection while 3 (15.8%) genes were upregulated 39 days post-infection. The present study lists the candidate genes of the NF-kappaB signaling pathway that were commonly and differentially expressed between the specific points of T. spiralis infection, thus suggesting that these genes need to be further investigated to reveal the mechanism of the T. spiralis modulation of the NF-kappaB signaling pathways.     

Stimulation of TH1 response by Helicobacter pylori neutrophil activating protein decreases the protective role of IgE and eosinophils in experimental trichinellosis

Th2 responses seem to play an important role in defence against Trichinella spiralis (Ts). The neutrophil Activating protein of Helicobacter pylori (HP-NAP), that induces IL-12, and IL-23 expression and shifts to Th1 allergen-specific Th2 cells in vitro was used as an anti-Th2 agent in BALB/c mice infected with T. spiralis. The muscle larvae (ML) burden was lower (p < 0.02) in untreated infected animals than those infected treated with HP-NAP. In both groups there was an inverse relationship between ML burden of each animal and total IgE level (controls: r -0.617, p = 0.0013 and HP-NAP-treated: r -0.678, p = 0.0001) or eosinophil count, evaluated in the same mouse on day 42 (r -0.390, p = 0.0592 and r -0.803, p = 0.0001, respectively). Inflammatory response around the nurse cell-parasite complex was significantly higher in HP-NAP-treated infected animals than in those untreated infected, on the contrary the number of eosinophils, counted around each complex was significantly lower in the first animal group. This study provides evidence of a powerful anti-Th2 activity in vivo by HP-NAP and for the partial protective effect of Th2 responses in T. spiralis infection.     

Microcapsules formulated in the enteric coating copolymer Eudragit L100 as delivery systems for oral vaccination against infections by gastrointestinal nematode parasites

Microcapsules using the copolymer of methacrylic acid (Eudragit L100) were formulated for oral delivery of vaccines against the enteral/parenteral nematode parasite Trichinella spiralis. Antigenic preparations from first stage larvae (L1) of T. spiralis were microencapsulated in Eudragit L100. The microcapsules prepared by the spray drying method were resistant to acid pH, although the antigen was rapidly released under neutral and basic environmental conditions. The native protein conformation and biological activity was preserved in the microcapsules, as assessed by SDS-PAGE and ELISA. When administered to NIH mice, the antigen loaded microcapsules protected against infection by T. spiralis at both the intestinal and muscular levels, the worm burden diminishing by 45.58 and 53.33%, respectively. Furthermore, following administration of the microparticles an increase of the serum IgG1 response, a marker for the Th2 type response, was evident. These results indicate that microcapsules formulated with anionic biocompatible polymers such as Eudragit may be useful for oral vaccination against nematode infections.     

Factors which determine the accumulation of immunoblasts in gut and skin.

The capacity of immunoblasts from two sources (1) peripheral lymph nodes draining the site of application of a contact sensitizer and (2) mesenteric lymph nodes from mice infected with the gut parasite T. spiralis to migrate to the gut and to inflamed skin sites were compared. The peripheral lymph node blasts readily entered skin sites in a non-specific way but failed to migrate to the gut even when inflammation was induced. By contrast, the mesenteric lymph node blasts readily migrated to the gut in normal mice and in increased amounts to the gut of mice infected with T. spiralis or inflamed with oral turpentine. A small proportion of mesenteric lymph node blasts did, however, migrate, non-specifically to the skin but in much smaller amounts than peripheral lymph node blasts. We conclude that the migration of immunoblasts to the gut has some specificity related to the source from which the cells were taken but little specificity with regard to intraluminal antigen.     

Toxicity of bis(tri-n-butyltin)oxide in the rat. II. Suppression of thymus-dependent immune responses and of parameters of nonspecific resistance after short-term exposure

To evaluate the functional significance of bis(tri-n-butyltin)oxide (TBTO)-induced thymus atrophy, lymphocyte depletion in spleen and lymph nodes, lymphopenia, and increased serum IgM and decreased IgG concentrations, in vivo and in vitro function studies were performed for specific and nonspecific resistance. Weaned male rats were fed diets containing 0, 20, or 80 mg TBTO/kg for at least 6 weeks. Regarding the thymus-dependent immunity, delayed-type hypersensitivity reactions to ovalbumin as well as tuberculin were significantly depressed at both dietary concentrations. Resistance to the nematode Trichinella spiralis was significantly suppressed as shown by a retarded expulsion of adult worms from the small intestine, increased counts of muscle larvae, reduced inflammatory reaction in parasitized musculature, and suppressed serum IgE titers. Also the secondary mercaptoethanol-resistant (presumably IgG) hemagglutinating antibody titer to sheep red blood cells was significantly reduced, while no significant alterations were found in IgM and IgG titers to T. spiralis, ovalbumin, and tetanus toxoid. TBTO exposure reduced the response of thymocytes in both treatment groups and of spleen cells in the 80-mg/kg group upon stimulation with T-cell mitogens and increased the response of spleen cells to B-cell mitogens. When calculated per whole spleen, the response to T-cell mitogens was strongly impaired but unaltered by B-cell mitogens. This difference can be explained by a relative increase of splenic B cells as a result of reduced numbers of T cells, as shown by cell surface marker analysis using monoclonal antibodies. Reduced splenic T-cell numbers appeared equally due to a decreased number of T helper and to T suppressor cells. From these data and from results of a time-sequence study in which effects of TBTO on cell count and cell viability of thymus, spleen, and bone marrow were investigated, it is concluded that TBTO-induced immunodeficiency was primarily due to its direct toxic action on thymocytes. When cultured in vitro in the presence of TBTO, viability of thymus and bone marrow cells was equally reduced, while after in vivo treatment viability of bone marrow cells was unaffected. Thus, the in vitro situation does not mimic the in vivo one. Concerning the nonspecific resistance, TBTO reduced macrophage function as shown by impaired splenic clearance of Listeria monocytogenes bacteria. From in vitro studies it is concluded that impaired in vivo splenic clearance was due to a reduction in both the number of adherent cells in the spleen and bacterial digestion on a cell for cell basis.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effect of Hexachlorobenzene on the Immune System of Rats Following Combined Pre- and Postnatal Exposure

ABSTRACT

The effect of HCB on the immune system was studied after combined pre- and postnatal exposure. Pregnant rats received diets containing 50 and 150 mg HCB/kg. Dosing continued during lactation and after weaning. At an age of 5 weeks the immune system was functionally assessed. in both treatment groups, the resistance to L.mono-cytogenes infection was suppressed, as was the resistance to an infection with T. spiralis (increased yield of muscle larvae). No effect was observed on allograft rejection or on mitogenic response of thymus and spleen cells. HCB enhanced the thymus-dependent antibody response to T.spiralis antigen and to tetanus toxoid (secondary IgG titers to tetanus toxoid were increased 16-fold in both test groups). No effect was found on the thymus-independent IgM response to LPS, on the passive cutaneous anaphylaxis and on the clearance of carbon particles and L.monocytogenes. HCB treatment caused morphologic changes in lymph nodes, lung and liver. It is concluded that HCB suppresses cellular immunity and enhances humoral immunity in both test groups. As effects on liver (increase in weight and microscopic changes) were only noted in the 150 mg/kg group, it is also concluded that the developing immune system seems particularly vulnerable to HCB.     

The effect of diethylstilbestrol as measured by host resistance and tumor susceptibility assays in mice

As part of a program to develop and validate methodology to measure chemically induced immunotoxicity, the effect of DES on resistance of adult B6C3F1 female mice to various microorganisms and to challenge with syngeneic tumor cells was evaluated. The mice received sc injections of 50 microliter corn oil alone or of corn oil containing the equivalent of 0.2, 1, and 4 mg DES/kg X d for 14 d. Three days later they were challenged with Listeria monocytogenes, Streptococcus sp. influenza virus, herpes virus, Trichinella spiralis, or B16-F10 tumor cells. Host resistance parameters were mortality for the bacterial and viral systems, expulsion of adult parasites from the gut for T. spiralis, and lung weights for the B16-F10 tumor-cell model. Host resistance to L. monocytogenes, herpes virus, and T. spiralis was significantly decreased following DES exposure. Resistance to Streptococcus sp. was decreased, but not at a statistically significant level following these doses of DES. However a dose of DES at 8 mg/kg X d resulted in a highly significant decrease in resistance to the organism. Resistance to influenza virus was unaffected by the DES. In contrast to the above, host resistance to iv-administered B16-F10 tumor cells was significantly increased as a consequence of DES exposure. These model systems for measuring alterations in host resistance have been indicated to hold potential for the routine screening of drugs, chemicals, and environmental agents for their possible immune effects, both adverse and potentiating. The results indicate the importance of selecting the appropriate assay for evaluating a particular agent. They also stress the necessity for including host resistance assays along with assays to measure specific immune aspects, in order to assess in the intact animal the overall effect of complex immune interactions following exposure to a test agent.