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1.
以日本血吸虫中国大陆株童虫为实验对象,研究比较了嗜酸粒细胞(Eos)的细胞毒效应对抗体和/或补体的依赖作用。正交设计的体外杀伤试验表明补体和抗体均可作为配体参与Eos杀伤日本血吸虫中国大陆株童虫的细胞毒效应作用;配体依赖作用的大小顺序为抗体 补体>补体>抗体;在新鲜免疫血清1∶20、培养48h、效/靶比5000∶1时童虫死亡率最高。  相似文献   

2.
用抗体依赖、细胞介导的细胞毒试验(ADCC)观察了小鼠感染后不同时间血清在体外杀伤系统中对日本血吸虫童虫的作用规律。未加补体时,嗜酸粒细胞或巨噬细胞介导的童虫杀伤作用于感染后4wk出现明显作用,分别于5—7wk和6—8wk达高峰,然后下降,至11wk时降至4wk时的水平;而未加补体时无明显的中性粒细胞介导的杀伤作用。在补体参与下,这三种细胞均能介导对童虫的杀伤作用,且作用增强。证实ADCC是日本血吸虫获得性抵抗力的一个重要组分,嗜酸粒细胞、巨噬细胞介导的对童虫的细胞毒作用是不依赖补体的,而中性粒细胞介导的作用是依赖补体的。结果对选择免疫预防适宜时间和评价候选疫苗效果有参考意义。  相似文献   

3.
本文报告运用体外免疫效应机理分析系统,证明了对日本血吸虫(中国大陆株)童虫的抗体依赖小鼠巨噬细胞介导的细胞毒作用(ADCC)。来源于正常小鼠和感染小鼠的巨噬细胞皆能产生对日本血吸虫童虫的依赖抗体介导的 ADCC 反应;感染小鼠巨噬细胞对童虫还具有不依赖抗体的细胞毒作用,而正常小鼠巨噬细胞则无;感染小鼠巨噬细胞参与的对童虫的 ADCC 反应较其不依赖抗体的细胞毒作用强,也较正常小鼠巨噬细胞参与的 ADCC 为强。还注意到补体仅可增强感染小鼠巨噬细胞的 ADCC 反应。  相似文献   

4.
运用体外免疫效应机理分析系统,证明了抗体依赖的小鼠中性粒细胞介导对日本血吸虫(中国大陆株)童虫的细胞毒作用(ADCC)。结果表明,正常小鼠的中性粒细胞能产生对日本血吸虫童虫的依赖抗体介导的ADCC反应,这种ADCC作用不依赖补体,补体对中性粒细胞介导的这种ADCC无增强作用。  相似文献   

5.
迄今已积累的研究资料表明,宿主感染血吸虫后产生的伴随免疫涉及多种免疫效应机理,其中抗体依赖的细胞介导的对童虫的细胞毒作用(ADCC),可能是主要免疫效应之一。本文综述了有关嗜酸粒细胞、中性粒细胞、单核-巨噬细胞参与的 ADCC 体外免疫效应机理的研究进展。嗜酸粒细胞依赖抗体的杀童虫作用分为两个步骤:即依赖细胞上的 Fc 受体与结合在童虫表面的抗体 Fc 段搭桥,随之细胞中颗粒的内容物作为配体促进其与童虫不可逆的结合,从而杀伤童虫。嗜酸粒细胞颗粒中的主要碱性蛋白、阳离子蛋白为主要的杀童虫物质,此外过氧化物酶-过氧化氢-卤化物系统可能也有一定的杀童虫作用。补体、肥大细胞的产物、淋巴因子等对嗜酸粒细胞介导的 ADCC 有促进作用。尽管在体外实验中,中性粒细胞有与嗜酸粒细胞相似的过氧化物酶-过氧化氢-卤化物系统杀伤童虫的机制,但其在保护性免疫表达中的作用迄今仍不明确。近年来,许多实验证明单核-巨噬细胞不仅在体外能依赖抗体特异地杀伤皮肤期童虫,而且因感染、免疫接种或无关抗原(如 BCG)的刺激激活的巨噬细胞能非特异杀伤皮肤期童虫和肺期童虫。巨噬细胞杀伤童虫的细胞毒机理尚不明确,可能与精氨酸酶和髓过氧化物酶有关。运用巨噬细胞功能缺陷的小鼠品系进行的体内诱导免疫力的研究,进一步支持巨噬细胞在抗血吸虫感染的保护性免疫的产生中可能起中心作用。  相似文献   

6.
以抗嗜酸粒细胞血清(AES)对嗜酸粒细胞(Eos)在日本血吸虫(中国大陆株)感染小鼠体内的作用进行了研究。小鼠经初次感染日本血吸虫尾蚴5wk后,用200条尾蚴攻击感染,并经AES处理,肺部回收童虫数明显高于用正常兔血清(NRS)处理的对照组;正常小鼠经被动转移免疫血清后感染日本血吸虫尾蚴,用AES处理,肺部回收童虫数比NRS对照组明显增多。用日本血吸虫可溶性虫卵抗原(SEA)皮下致敏小鼠,2wk后经尾静脉注射虫卵形成肺肉芽肿反应,经AES处理后,肺虫卵肉芽肿内Eos受到明显抑制,肉芽肿平均直径明显小于NRS对照组。试验结果提示,Eos是宿主体内对日本血吸虫童虫有效的杀伤细胞之一,其杀伤作用是抗体依赖的Eos介导的细胞毒作用;AES能特异性地仰制肉芽肿内的Eos,并对不同时期肉芽肿的直径有明显的抑制作用。  相似文献   

7.
通过比较日本血吸虫感染病人与正常人血清体外诱导小鼠白细胞杀童虫的作用,了解抗体依赖的细胞介导的细胞毒作用(ADCC)在血吸虫感染宿主的获得性免疫中的作用.体外诱导小鼠白细胞杀童虫作用,日本血吸虫感染病人血清,无论是成人组还是儿童组,初次感染组还是重复感染组,均明显地强于正常人血清,表明抗血吸虫特异性抗体可以诱导细胞介导的细胞毒作用.证明日本血吸虫感染宿主体内存在着ADCC机制,该机制对于抵抗再次感染具有一定的作用,是日本血吸虫获得性免疫的重要组分.  相似文献   

8.
对丝虫微丝蚴和感染期幼虫的抗体依赖细胞介导的细胞毒作用(ADCC)可能是宿主抗丝虫感染的主要免疫效应机制。参与作用的抗体类型和效应细胞可因虫种而异。效应细胞通过其细胞膜上的Fc受体与结合于虫体表面的抗体Fc段桥连,进而释放各种毒性物质作用于虫体,导致虫体死亡。抗体和补体同时存在时,效应细胞能对虫体发挥最大的杀伤效应,效应细胞表面的补体受体在其中起了重要作用。另外,补体还能单独介导效应细胞实施对虫体的攻击。  相似文献   

9.
在体外试验系统中,特异性抗血清或各种效应细胞单一因素与日本血吸虫童虫作用,对童虫一般不出现有意义的杀伤作用。但当两者共同作用于虫体时,则可使粘附各种效应细胞的童虫比率和童虫死亡率显著增高。这种作用在一定范围内随着特异性抗体的浓度、效应细胞与童虫的比率(效一靶比率)和孵育时间的增加而增强。在同样条件下,一般均以巨噬细胞(Mφ)和嗜酸性粒细胞(Eos)的作用较强,中性粒细胞(Neu)作用较差。显微镜下观察可见Mφ和Eos紧密粘附于虫体表面,致虫体表面出观明显损伤。而Neu在虫体粘附一定时间后自由体脱落,童虫结构相对比较完整。  相似文献   

10.
通过比较日本血吸虫感染病人与正常人血清体外诱导小鼠白细胞杀童虫的作用。了解抗体依赖的细胞介导的细胞毒作用(ADCC)在血吸虫感染宿主的获得性免疫中的作用。体外诱导小鼠白细胞杀童虫作用。日本血吸虫感染病人血清,无论是成人组还是儿童组,初次感染组还是重复感染组,均明显地强于正常人血清,表明抗血吸虫特异性抗体可以诱导细胞介导的细胞毒作用。证明日本血吸虫感染宿 主体内存在着ADCC机制。该机制对于抵抗再次感染具有一定的作用。是日本血吸虫获得性免疫的重要组分。  相似文献   

11.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

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Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.  相似文献   

14.
Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.  相似文献   

15.
Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

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Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the Mr range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [125I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (Ka of 4.7 ± 0.2 × 109 M-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of Mr 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.  相似文献   

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PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.  相似文献   

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