Influence of cadmium on the course of intestinal and muscular phases in mice infected with Trichinella spiralis]

At the first experiment 20 Swiss male mice were infected with 100 larvae and 20 mice with 500 larvae T. spiralis per mouse. Two days after infection (d.a.i.) mice orally received 1.5 mg Cd (water solution CdCl2) each. 40 mice were infected only T. spiralis as control. At the second experiment muscle larvae used were isolated from mice (from the first experiment) which received Cd. 20 mice were infected with 100 larvae and 20-with 500 larvae per mouse. Two d.a.i. mice received 1.5 mg Cd. Mice from both experiments were killed at 5, 10, 20 and 42 d.a.i. Total number of adult T. spiralis worms present in the small intestine and muscle larvae were recovered by conventional technique. Results of the first experiment: the number of adult worms and muscle larvae recovered from mice received Cd. were statistically significant lower as in control. Results of the second experiment: the mean number of adult worms in experimental group and in control were the same but the mean number of larvae per gram of mice muscle were significant higher as in control.     

旋毛虫在小鼠先天性传播的初步研究

目的?摇研究旋毛虫在小鼠的先天性传播并观察母鼠抗旋毛虫抗体对攻击感染的保护作用。 方法 将昆明小鼠分为受孕后感染组和感染后受孕组，子鼠出生后1 d内剖杀，检查旋毛虫幼虫；将正常母鼠所产子鼠由感染旋毛虫的母鼠喂养，21 d后宰杀，检查旋毛虫幼虫。用间接ELISA检测感染母鼠所产子鼠出生后不同时间的血清抗旋毛虫抗体，观察母鼠抗旋毛虫抗体对攻击感染的免疫保护。 结果 受孕后7 d感染旋毛虫的母鼠所产的6只子鼠中有2只感染旋毛虫；感染旋毛虫后8 d和22 d受孕雌鼠所产子鼠的感染率分别为20%（2/10）和25%(2/8)，从子鼠检获的旋毛虫均是未成囊的幼虫。交叉哺乳实验表明正常母鼠所产的30只子鼠未见旋毛虫感染。感染母鼠所产27只子鼠出生后1、7、24及40 d的血清抗体阳性率分别为100%、100%、77.8%及14.8%，子鼠出生后40 d攻击感染的减虫率为62.0%；感染母鼠所产子鼠血清被动转移小鼠的减虫率55.7%，与对照组比较差异有显著性（P<0.01）。 结论 旋毛虫在小鼠可经胎盘传播，母鼠的抗旋毛虫抗体对子鼠抗攻击感染可能具有部分保护作用。     

Altered intestinal fluid movement in response to Trichinella spiralis in immunized rats

Net intestinal fluid movement was measured in immunized and non-immunized rats infected with the enteric stages of the nematode, Trichinella spiralis. Animals were studied 30 min, 5 days and 30 days after receiving infective larvae. Net water movement across the mucosal surface of the gut was measured in vivo by perfusing a cannulated segment (approximately 30 cm) of proximal small intestine with an isotonic solution containing a nonabsorbable marker, 14C polyethylene glycol, at a rate of 0.5 ml/min. Uninfected rats showed net absorption of water, 25 microliter/h per cm of intestine. This response was unaltered when rats were infected (7 x 10(3) larvae/rat) and examined 30 minutes later. Five days after primary infection net tissue-to-lumen fluid movement, ie. net secretion, occurred at a rate of 45 microliter/h per cm. When rats were studied 30 days after primary infection, net absorption equivalent to the preinfection level was observed once again. Previously infected (immunized) rats, when challenged (secondary infection, 7 x 10(3) larvae/rat) and examined within 30 min showed a significant decrease in net absorption rate as compared with non-immunized rats. Absorption returned to the preinfection level at both 5 and 30 days post challenge. Results support the conclusion that T. spiralis caused a decrease in net lumen-to-tissue fluid movement during primary and secondary infections. The response was initiated faster in previously infected hosts. The rapid induction of net fluid movement in the direction of secretion upon secondary contact with the parasite is associated temporarily with prevention of worm establishment.     

Enhanced resistance to Plasmodium berghei in mice previously infected with Trichinella spiralis

Infection with Trichinella spiralis larvae greatly enhanced the resistance of adult mice against fatal infection with Plasmodium berghei given 10 and 30 days after T. spiralis infection. Mice infected with T. spiralis had a markedly activated mononuclear phagocytic system and significantly low reticulocyte levels at the time the mice were challenged with P. berghei. Therefore, the partially subdued parasitaemia and prolonged survival of Trichinella—Plasmodium -infected mice may be attributed, in part, to macrophage activity and reticulocytopenia exerting a specific anti- P. berghei effect. This study suggests the role of T. spiralis induced reticulocytopenia and activated macrophages as potential mechanisms in resistance to P. berghei infection.     

Antibody-mediated in-vivo cytotoxicity to Trichinella spiralis newborn larvae in immune rats

The antibody-dependent cell-mediated larvicidal response of AO rats against Trichinella spiralis newborn larvae was studied in vivo. Rats were immunized with 2000-3000 muscle larvae orally and then challenged 6-20 days later with 10,000-20,000 newborn larvae intraperitoneally. Newborn larvae recovery from the peritoneal cavity decreased significantly and was accompanied by cuticular cell adherence and killing of newborn larvae by day 9 of infection. Similar effects were observed when newborn larvae were incubated with blood obtained from immunized rats. The cell adherence and larvicidal responses reached their peak by day 16 of the primary infection. Passive transfer experiments demonstrated that newborn larvae infectivity was substantially impaired once cell adherence occurred. Cuticular adherence took place in vitro only when immune serum was added to the incubation medium. Complete destruction of newborn larvae in vivo after passive transfer, as measured by muscle larvae burden was only evident after exposure to both immune serum and immune cells, not to either alone. Non-specific stimulation of the peritoneal cavity with a sterile intestinal infection failed to induce cuticular adherence or larval killing in these rats. We conclude that a stage-specific antibody-dependent cell-mediated larvicidal response is rapidly generated in vivo after the host is exposed to newborn larvae. It is a systemic response which impairs the infectivity of newborn larvae and can destroy them before they reach muscle tissue.     

旋毛虫感染小鼠IgG、IL-2和T淋巴细胞亚群动态变化的观察

目的　了解小鼠感染旋毛虫后 Ig G抗体水平、IL - 2分泌量和 T淋巴细胞亚群的动态变化。方法　分别于旋毛虫感染后第 7、14、2 1、2 8和 35天 ,采用 EL ISA方法检测血清特异性 Ig G抗体水平和 IL- 2含量 ,采用流式细胞仪检测 CD4+、CD8+T细胞百分率。结果　 Ig G抗体水平在感染后逐渐上升 ,感杂后 35天达最高值 ;T淋巴细胞的变化表现为 CD4+T细胞减少、CD8+T细胞增多 ,CD4+/ CD8+细胞比值下降 ,以感染后第 14天最为显著 ,直到感染后第 35天仍未见恢复。IL - 2分泌量以感染后第 7天达高峰 ,然后迅速下降 ,到感染后第 35天低于正常组。讨论　旋毛虫感染的急性期 ,小鼠出现免疫抑制现象。抗旋毛虫感染的保护性免疫是由细胞免疫与体液免疫协同完成的。     

Suppression of mucosal mastocytosis by Nematospiroides dubius results from an adult worm-mediated effect upon host lymphocytes

Infections with the nematode Nematospiroides dubius fail to elicit mucosal mast cell (MMC) responses in the intestines of host mice, and suppress MMC responses generated by heterologous infection. Larval N. dubius have the capacity to prime for mastocytosis, and to elicit this response in primed mice during a challenge, but only if adult worms are prevented from developing, either by anthelmintic treatment or by irradiation of the larvae themselves. The suppressive effect of the adult stage was confirmed in experiments where such worms were implanted directly into the intestines of mice primed by exposure to irradiated N. dubius larvae or concurrently infected with Trichinella spiralis. Data on the mechanisms underlying this suppressive effect were obtained from experiments involving the adoptive transfer of mastocytosis by mesenteric lymph node cells (MLNC) from T. spiralis infected mice. When MLNC were taken from mice infected concurrently with both T. spiralis and N. dubius no enhanced mastocytosis was seen in recipients after challenge with T. spiralis. Exposure of MLNC from T. spiralis infected donors to the presence of adult N. dubius after transfer did not reduce the adoptively transferred response. The response was also unaffected when MLNC from adult N. dubius infected mice were simultaneously transferred with MLNC from T. spiralis donors. It is concluded that the suppressive effect of adult N. dubius upon the expression of mucosal mastocytosis acts upon the generation of lymphocytes capable of promoting the development of MMC from precursor cells.     

Detection of Trichinella spiralis antigens in urine of men and animals

The practical inability to diagnose Trichinella spiralis antibodies in man before day 20 post infection (dpi) has stimulated interest in the development of immunodiagnostic test to detect circulating antigens. Our previous experience showed that soon after infection immune complexes as well as uncomplexed parasite antigens in sera of infected rats could be detected. To diagnose the presence of antigen in urine, double sandwich-capture ELISA was applied using a peroxidase-conjugated rabbit immunoglobulin to T. spiralis larval antigens. The plates were coated with metabolic (AES) or somatic (AS) larval antigens. Mice were infected with 500 T. spiralis larvae. The urine samples from experimentally infected mice taken from 1 to 41 dpi. and the urine samples from patients of the Clinical Hospital in Bia?ystok taken from 3 to 120 dpi were examined. Before testing, the urine samples were heated for 6 min. at 100 degrees C and centrifuged for 6 min. at 5000 g, supernatants were used in ELISA. The presence of T. spiralis antigens in mice urine samples was detected between 6-26 days post infection (dpi) using double sandwich-capture ELISA. All samples taken later were negative as samples taken from uninfected mice. 3 from 9 human urine samples taken 3-10 dpi were positive, the remaining samples taken 3-10 and 10-30 dpi showed values near to "cut-off". In both mice and human urine samples the higher level of antigens was detected in ELISA when somatic larval antigen was used. The T. spiralis antigens were present in urine of infected men and mice in the first phase of infection.     

旋毛虫肌幼虫体外生存状况实验研究

目的观察旋毛虫肌幼虫在干燥和生理盐水环境中的生存状况。方法90只昆明小鼠被随机分为正常对照组、生理盐水组和干燥组,生理盐水组和干燥组分别再分为4组,共9组,每组10只。正常对照组每鼠经口感染200条收集的肌幼虫。生理盐水组分为4组：①肌幼虫0℃放置10 d,②肌幼虫20℃放置10 d,③肌幼虫0℃放置20 d,④肌幼虫20℃放置20 d;干燥组分组与生理盐水组相同。然后将8组小鼠每鼠经口感染200条处理的肌幼虫。感染后30 d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。结果在生理盐水和干燥环境中放置10 d的肌幼虫分别感染小鼠后,压片法和人工消化法镜检,感染小鼠的幼虫检出率均为100%;在生理盐水和干燥环境中放置20 d的肌幼虫分别感染小鼠后,两种方法镜检,感染小鼠均未检出幼虫。结论在生理盐水和干燥环境中,肌幼虫能生存较长时间,但不超过20 d。     

流式细胞术测定感染旋毛虫小鼠免疫功能的研究

目的观察感染旋毛虫小鼠免疫功能的动态变化.方法采用流式细胞术分别检测感染旋毛虫后7、14、21、28、35d小鼠外周血CD4+、CD8+T淋巴细胞的百分率.结果实验组较正常组CD4+T细胞减少,CD8+T细胞增多,CD4+/CD8+细胞比值下降(P＜0.05),以感染后第14d最明显,直到感染后35d仍未见恢复.结论感染旋毛虫的小鼠出现免疫抑制现象,感染急性期的免疫抑制程度最高.     

旋毛虫成虫可溶性抗原免疫小鼠攻击感染后的免疫应答

目的　探讨旋毛虫成虫可溶性抗原 (AWSAg)接种小鼠后诱发的免疫应答。　 方法　制备旋毛虫AWSAg免疫小鼠 ,分别于攻击感染后 7、14、2 1、2 8和 3 5d ,动态观察免疫小鼠特异性IgG抗体水平、IL 2水平和T淋巴细胞亚群的变化。　结果　与非免疫鼠相比 ,免疫鼠血清特异性IgG抗体OD值在攻击感染后 7d明显升高 ,在观察期内一直高于非免疫鼠。感染后 7dIL 2水平明显增高 ,达观察期内最高值 ,2 1d后才逐渐减少 ,在感染后 2 8～ 3 5d仍高于正常组。免疫鼠CD4+ T细胞在攻击感染 7d明显增加并保持不变 ,非免疫鼠CD4+ T细胞及CD4/CD8比值明显较正常鼠减低。　结论　旋毛虫AWSAg免疫小鼠攻击感染后 ,出现细胞、体液免疫应答。     

旋毛虫成虫可溶性抗原免疫小鼠T淋巴细胞亚群的动态变化

目的　观察旋毛虫成虫可溶性抗原免疫小鼠T淋巴细胞亚群的动态变化。方法采用流式细胞术分别检测旋毛虫感染后 7、14、2 1、2 8、35天小鼠外周血CD+ 4 、CD+ 8T淋巴细胞的百分率。结果　免疫小鼠CD+ 4 、CD+ 8细胞增加 ,CD+ 4 /CD+ 8细胞比值与正常组比较无明显差异。结论　旋毛虫成虫可溶性抗原免疫小鼠未出现免疫抑制现象     

旋毛虫幼虫在大鼠与小鼠肌肉分布及囊包内幼虫数量的观察

目的观察不同剂量旋毛虫感染大鼠与小鼠后幼虫在肌肉内的分布及囊包内的幼虫数量。方法将30只昆明小鼠和30只SD大鼠均随机分为轻、中、重度感染组(每组10只),分别按每g克体重1、5、20条肌幼虫经口感染。感染后42d剖杀,取不同部位肌肉称重后压片镜检,观察不同部位每克肌肉虫荷(larvaepergram,lpg)及囊包内幼虫数量。结果大鼠在轻度感染时以咬肌虫荷最高,中、重度感染时分别以膈肌和舌肌虫荷最高;小鼠在轻度感染时以咬肌虫荷最高,中、重度感染时均以膈肌虫荷最高。在大鼠肌肉8028个囊包中,含1、2、3条幼虫的囊包分别占97.91%、1.95%及0.14%;在小鼠肌肉7559个囊包中,含1、2、3条幼虫的囊包分别占97.33%、2.54%及0.13%。小鼠肌肉多幼虫(2～3条)囊包的检出率明显高于大鼠(χ2=5.644,P<0.05)。多幼虫囊包的检出率在大鼠和小鼠均随感染剂量的增加而升高(χ2大鼠=42.656,P<0.05;χ2小鼠=45.713,P<0.05);在含3条幼虫囊包的肌肉,重度感染的大鼠和小鼠肌肉分别占81.82%(9/11)与100%(10/10)。未发现含有4条及4条以上幼虫的囊包。结论对鼠类旋毛虫感染的流行病学调查时应首选咬肌进行病原学检查,其次为膈肌或舌肌;进行肌肉活检或肉类检疫时发现含3条幼虫的囊包提示为重度感染。     

The effect of toluene and ammonia on the invasive process and immunological indices in experimental trichinelliasis in mice]

Rap mice were exposed to toluene (T) inhalation for 10 days before invasion with 20 Trichinella spiralis larvae per g body weight (moderate infection). This resulted in diminished number of intestinal parasites in the presence of greater number of mast cells in the peritoneal exudate, higher IgE production, enhanced cell adhesion to trichinella larvae and of migration of splenic lymphocytes. Simultaneous inhalation of T and ammonia diminished the immune stimulating effect of the former. The number of intestinal trichinella was 1.5 times more but still twice less than in controls. Inhalation of T during the first 10 days of infection stimulated the immune response only in mice given 5 larvae per g. In those given 20 or 60 larvae per g, the immune response was suppressed and 40 and 100% of mice perished respectively. The exposure to T during 30-39 days of infection of mice given 35 larvae per g (the intensive infection) resulted in 50% death of the animals without significant changes in immune response. Simultaneous therapy with mebendazole (75 mg/kg) provided 100% survival in the presence of suppressed immune response. 100% of mice of the same group not exposed to T but treated with mebendazole died. The toxic and immunomodulating effects of T differ in intact and infected mice due to the dense, the stage of infection and to chemotherapy.     

甲苯咪唑、阿苯达唑对旋毛虫感染小鼠毛中微量元素含量的作用

目的研究甲苯咪唑(MD)、阿苯达唑(AD)治疗对旋毛虫感染所致小鼠毛中Zn、Cu、Fe3种微量元素含量变化的影响。方法将小鼠分组,用提取的旋毛虫肌肉幼虫感染小鼠,建立不同感染度的旋毛虫病模型,于感染后第7w分别给予一次性口服MD、AD50mg/kg,同时设置空白对照组和旋毛虫感染非治疗对照组,于感染后第15w,测量各组小鼠毛中Zn、Cu、Fe的含量,并观察其膈肌病理变化。结果旋毛虫感染导致小鼠毛中Zn、Cu、Fe3种微量元素的含量较正常对照组明显降低(P<0.05),其中,重度感染组又显著低于轻度感染组(P<0.05)。在感染后第7w应用MD、AD治疗的小鼠,Zn、Cu、Fe3种微量元素均得以显著提高,与感染未治疗组相比,差异显著(P<0.05)。病理观察显示,治疗组囊包周围炎症较轻,可见透明带和钙盐沉积。结论MD、AD治疗可以减轻旋毛虫感染小鼠的病变程度,使因感染所致的鼠毛中Zn、Cu、Fe3种微量元素的含量的降低得到不同程度的恢复。     

肉类中旋毛虫成囊前期幼虫检验方法及其影响因素

目的观察人工消化法(artificial digestion method)和贝氏法(Baermann's technique)检验肉类中旋毛虫成囊前期幼虫(pre-encapsulated larvae,PEL)的效果及其影响因素。方法将45只小鼠随机分为3组(每组15只),分别经口感染20、10、5条旋毛虫肌幼虫,感染后18d剖杀,将3组小鼠肌肉剪碎后,分别应用国际旋毛虫病委员会(International Commis-sion on Trichinellosis,ICT)推荐的消化法(简称ICT-消化法)、国家标准-猪旋毛虫病诊断技术(GB/T186452-2000)中规定的消化法(简称国标-消化法)及贝氏法进行PEL的检验。结果ICT-消化法、国标-消化法与贝氏法对感染20条旋毛虫幼虫的小鼠肌肉中PEL的检出率均为100%(15/15)(χ220=0.000,P>0.05);感染10条幼虫小鼠肌肉,3种方法的PEL检出率分别为93.33%(14/15),93.33%(14/15)及100%(15/15)(χ120=1.645,P>0.05);感染5条幼虫的小鼠肌肉,3种方法的PEL检出率分别为63.33%(19/30),90%(27/30)及100%(30/30)(χ52=18.866,P<0.05)。感染旋毛虫后18d的小鼠肌肉分别消化1h、2h、3h、4h与5h,PEL死亡率分别为8.49%(53/624)、29.77%(181/608)、58.46(449/768)、67.83%(407/600)、84.70%(515/608),PEL的死亡率随消化时间的延长而升高(χ2=920.772,P<0.05)。结论对肉类中旋毛虫成囊前期幼虫检疫时,贝氏法明显优于消化法。     

Influence of nalcrom (sodium cromoglycate) on the course of the intestinal phase of trichinellosis in mice]

The influence of Nalcrom (sodium cromoglycate) on the course of the intestinal phase of trichinellosis in mice was investigated. The animals infected with 200 Trichinella spiralis larvae were treated with Nalcrom between 7-20 or 3-20 days after infection (d.a.i.). The drug was administered in two doses: 0.6 or 1.7 mg/mouse/day. In the all groups of animals received Nalcrom higher number of mast cells and eosinophils than in the control groups was observed. These results are the opposite of those obtained with Nalcrom in ulcerative colitis in man.     

旋毛虫编码新生幼虫p46 kDa抗原基因重组融合蛋白对小鼠的免疫保护性研究

目的 探讨旋毛虫编码新生幼虫p46 kDa抗原基因重组融合蛋白WN10对小鼠的免疫保护性。方法 将纯化的重组融合蛋白WN10以20μg/只的剂量分3次免疫小鼠后，攻击感染旋毛虫肌幼虫200条／只，检查旋毛虫7日龄成虫数、雌虫体外产生新生幼虫数、感染35d的肌幼虫数并计算减虫率，同时用ELISA法检测血清中抗WN10抗体IgG滴度。结果WN10免疫小鼠后获得旋毛虫7日龄成虫、肌幼虫的减虫率分别为64．28％和61．21％，均与感染对照组和佐剂对照组差异显著；获得雌虫产新生幼虫的减虫率为16．46％，与感染对照组和佐剂对照组差异不显著；WN10免疫组小鼠在第3次免疫后1周可检测到高滴度的抗WN10抗体IgG，在攻击感染旋毛虫9周后仍维持在较高水平。结论 编码旋毛虫新生幼虫p46 kDa抗原基因重组融合蛋白可诱导小鼠产生较强的抗旋毛虫保护性免疫。     

旋毛虫幼虫侵入小鼠肠上皮细胞后细胞蛋白变化的研究

目的观察旋毛虫幼虫侵入前后小鼠肠上皮细胞蛋白的变化，筛选幼虫侵入相关蛋白。方法将旋毛虫感染性幼虫接种至小鼠小肠上皮细胞（intestinal epithelial cells，IECs）单层，于37℃5％CO2条件下培养2h，提取细胞蛋白，进行SDS-PAGE与Western blot分析，并与正常IECs细胞蛋白比较。结果SDS-PAGE分析表明，IECs与感染性幼虫共孵育后的IECs蛋白带数为44条，与正常IECs对照组的相同；Western blot显示，正常IECs蛋白不能被旋毛虫感染鼠血清识别，与幼虫共孵育后的IECs蛋白有16个组分带能被旋毛虫感染鼠血清识别，分子质量单位分别为125、118、106、98、70、64、50、47、46、40、34、33、31、29、27、26ku。结论小鼠IECs与旋毛虫幼虫共培养可产生能被旋毛虫感染鼠血清识别的细胞蛋白，该组蛋白可能是旋毛虫侵入相关蛋白。     

旋毛虫肌幼虫在感染小鼠体内的分布

目的观察旋毛虫肌幼虫在感染小鼠体内不同部位横纹肌内的分布和密度。方法分别取感染旋毛虫小鼠的舌肌、咬肌、胸肌、腹肌、前肢肌、后肢肌、膈肌和背肌各50mg,肌肉压片镜检。结果膈肌幼虫密度最高,其次为舌肌、胸肌;前肢肌、后肢肌、咬肌、背肌幼虫密度无明显差异,均低于胸肌,腹肌幼虫密度最低。结论感染旋毛虫的小鼠从膈肌取材,检出肌幼虫的阳性率较其他部位高。