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1.
<正> 引言 百日咳菌苗传统的形态,由杀死的百日咳杆菌组成,亦即它是全细胞菌苗。这种菌苗包含有对促进保护性应答不需要的成份,而且这些成份可能对副反应起作用。在日本,自1973年一直从事由百日咳杆菌分离其有效因子,并尽可能多的除去不需要的成份。一些保护性抗原已在百日咳杆菌培养物的上清液中被证实,并曾尝试发展一种由一或两种这些抗原组成的菌苗。含有两种主要保护性抗原即由百日咳杆菌培养物上清液中分离出的百日咳毒素(PT)和丝状血凝素(FHA)的精制百日咳菌苗(无细胞百日咳菌苗),自1981年已应用于日本.  相似文献   

2.
<正>百日咳是由百日咳杆菌引起的一种急性呼吸道传染病,严重威胁婴幼儿健康,对它的控制迄今主要依赖于菌苗预防。目前认为,百日咳杆菌有许多生活学活性成份,包括白细胞增多促进因子(LPF)[又称百日咳毒素(PT)]、丝状血凝素(FHA)、腺苷酸环化酶(AC)、外膜蛋白、脂多糖、不耐热毒素等。其中LPF、FHA、69KD外膜蛋白作为保护性抗原成份,是目前国内外学者研究的热点。  相似文献   

3.
百日咳毒素的基本分子结构、基本特性、基因结构和表达调控等方面的进展以及用基因工程方法生产百日咳毒素或百日咳毒素遗传脱毒的类似物的方法,为今后发展新一代百日咳基因工程菌苗,提供了参考。  相似文献   

4.
<正>近十年来,已研究开发了若干种无细胞百日咳菌苗,并有望取代当今使用中的全细胞菌苗。百日咳菌苗有多种抗原,如百日咳毒素(PT)、丝状血凝素(FHA)、菌毛混合物(Fim2+3)及69KDa外膜蛋白是无细胞菌苗之所需组分。最近在美国开展了旨在比较全细胞和13种无细胞菌苗免疫原性和反应原生力2期临床试验。这些无细胞菌苗或只含有PT,或由PT与上述的1种或1种以上的抗原组合而成,并已通过化学处理或对其菌体作遗传学修饰消除了毒注。进入2期临床试验的无细胞菌苗,不  相似文献   

5.
无细胞百日咳菌苗纯度和生物学特性研究   总被引:1,自引:0,他引:1  
本文对无细胞百日咳菌苗的纯度、免疫力和毒性进行了研究。实验证明菌苗中不仅含有百日咳毒素(PT)和丝状血凝素(FHA),而且还含有百日咳凝集素和百日咳粘着素。菌苗的纯度为50%-95.7%,菌苗中PT和FHA的比例为1:1-1:18。  相似文献   

6.
<正>最近已报道了百日咳毒素基因的整个序列及氨基末端序列,一级结构的明确使合或携带自然毒素抗原决定簇的肽链成为可能。短肽的抗体与天然蛋白常常结合得很好,因为这种蛋白提供的短肽序列是暴露在分子表面的。百日咳毒素由5个不同的亚单位组成,S_1—S_5。我们和其它学者已经发现,具有酶活性的亚单位S_1是免疫显性的。本研究用接种过全细胞百日咳菌苗或只含百日咳毒素菌苗的人和动物血清,对包含S_1亚单位抗原决定簇的5种多肽序列的鉴定及合成作了阐述。  相似文献   

7.
<正>本文综述了毒素产生的基因修饰和选择性位点特异性类似物分析以及它们用于制备高限性、非反应原性重组全类毒素菌苗的可能性。 许多研究工作者认为,PTX是百日咳菌苗的一种重要成分。也已公认化学或热处理的脱毒方法能消除PTX的反应原物质并导致保护性免疫原性的丧失。我们相信能够消除这种变性的蛋白结构基因工程,在合理设计新百日咳类毒素方面能具有极有意义的影响。  相似文献   

8.
<正>日本是成功地采用无细胞百日咳菌苗进行基础和加强免疫的唯一国家。那里的百日咳发病数已经明显下降。本文报道采用无细胞百日咳菌苗前后的百日咳流行病学,接种全细胞或无细胞百日咳菌苗后的临床病徵及今后日本百日咳免疫接种的方针。  相似文献   

9.
<正>由英国“应用微生物学及研究中心”研制的无细胞百日咳菌苗,含有凝集原2及3,百日咳毒素和丝状血凝素。188名婴儿进入一项随机的双盲试验,以联合白喉及破伤风类毒素的无细胞或全细胞菌苗按3、5及8~10个月的间隔进行接种。两组的局部反应相以,但在接种无细胞菌苗后,具有全身反应的婴儿显著地少于全细胞菌苗。对无细胞菌苗凝集原和毒素组分的抗体平均对致滴度高于全细胞菌苗。接种第三剂菌苗后一年,无细胞组抗体的持久性亦较好。  相似文献   

10.
<正>全细胞百日咳菌苗的效力通过小鼠保护试验(AMPT)来判定。此法是用不同稀释度的百日咳国际参考苗(ZSPV)和待检菌苗免疫小鼠,14天后脑腔攻击Bordetella百日咳菌18323(100-1000LD50)。 从1951年到1959年,由医学研究委员会进行的现场研究表明,能使小鼠抵抗脑腔攻击的百日咳菌苗也可保护儿童。尽管在AMPT的结果和接种的个体产生的保护力之间有高度的相关性,此试验仍有许多操作上的困难:(i)需要大量可对百日咳菌苗的免疫产生应答的小鼠。这些动物须在适宜的环境中喂养一个月,费用很高;(ii)脑腔注射需要毒株;(iii)实验室间和实验室内的结果有很大的  相似文献   

11.
将细菌内毒素检查法(凝胶法)扩大应用于乙脑灭活疫苗的质量控制及其内毒素的检测.按<中国药典>及<中国生物制品规程方法>方法,复核鲎试剂灵敏度、确定疫苗的L值、计算MVD、进行干扰试验及内毒素的检测.疫苗L值确定为300 EU/mL,MVD为1 200倍.用灵敏度0.25 EU/mL的鲎试剂,疫苗的最大非干扰浓度为将其稀释30倍,将此疫苗稀释120倍进行干扰试验,对内毒素的检测无干扰作用.以此法对15批疫苗进行内毒素检查均呈阴性反应.结果显示,此法用于乙脑灭活疫苗质量控制及其内毒素检查是可行的.  相似文献   

12.
百日咳杆菌69KDa外膜蛋白的分离纯化及生物学特性研究   总被引:1,自引:0,他引:1  
本文发展了一种从百日咳杆菌Ⅰ相菌株中纯化69KDa外膜蛋白的简易方法,将细菌体经加热浸提、乙醇沉淀蛋白、DEAE-Sephadex A50柱层析精制而成。用SDS-PAGE、免疫印迹、光密度仪扫描分析,证明纯化制剂为均一的、特异性的69KDa外膜蛋白,其收率为54.2%,纯度达99.2%,每微克69KDa蛋白制剂中的内毒素含量低于0.85EU;PT残留量小于0.105ng。抗69KDa蛋白抗血清能  相似文献   

13.
Biological properties of endotoxins prepared from three strains of Vibrio parahaemolyticus were compared with reference to commercially prepared Salmonella typhi endotoxin. Endotoxin assays performed in rabbits included dermal Shwartzman reactivity, pyrogenicity, heat stability, and ability to induce tolerance as well as cross-tolerance. Mice were used for endotoxin LD50 determinations. Results showed V. parahaemolyticus endotoxins were similar to that of S. typhi strain O901. Induction of tolerance to V. parahaemolyticus strain 11590 endotoxin resulted in complete cross-tolerance to S. typhi endotoxin, and vice versa. Partial cross-tolerance to S. typhi endotoxin was demonstrated with rabbits rendered tolerant to endotoxin from V. parahaemolyticus strains Sak-3 and FC1011. Absorption spectra, nitrogen, phosphorus and carbohydrate analyses revealed additional similarities between endotoxins from V. parahaemolyticus and endotoxin from a member of the Enterobacteriaceae.  相似文献   

14.
Comparison of lipopolysaccharides (LPS) from phase variants of different strains of Bordetella phase variants of different strains of Bordetella pertussis has shown a difference in their composition, antigenicity and reactogenicity. Phase I variants of B. pertussis, with the exception of strain 134, contain a preponderance of LPS I whereas the major component of LPS of phase IV variants is LPS II. Sera raised to LPSs of phase I strains, other than 134, cross-react with each other but not with phase IV LPSs; and similarly all sera raised to phase IV LPSs cross-react with each other and with LPS from 134 phase I. The LPSs of all phase I variants, including that of 134, are approximately ten-fold or more reactive in the limulus amoebocyte lysate assay (LAL) than phase IV LPSs. In the human mononuclear cell pyrogen assay phase IV LPSs also stimulated a lower response than phase I LPSs. The B. pertussis phase I LPSs are 10-times more reactive than Escherichia coli standard endotoxin in the LAL assay but 100-times less reactive than E. coli LPS in the monocyte test for pyrogen. The SDS-PAGE profiles of B. pertussis LPSs are quite different from those of B. parapertussis and B. bronchiseptica strains. B. pertussis LPSs produced a typical lipo-oligosaccharide (LOS) pattern. B. bronchiseptica LPS produced a similar pattern but was antigenically distinct from B. pertussis LPSs I and II. B. parapertussis in contrast produced a ladder pattern typical of smooth type LPS.  相似文献   

15.
An ampouled preparation of bacterial endotoxin, coded 84/650, was evaluated in 35 laboratories in 12 countries for its suitability to serve as the International Standard for Endotoxin. The ampouled preparation was calibrated in terms of the USA National Standard, EC5, in Limulus Amoebocyte Lysate gelation, turbidimetric and chromogenic tests and in rabbit pyrogen tests. On the basis of the results reported here, with the agreement of the participants in the study, and with the authorization of the Expert Committee on Biological Standardization of the World Health Organization, the preparation coded 84/650 was established in 1986 as the International Standard for Endotoxin for Limulus Gelation Tests with an assigned unitage of 14,000 IU of endotoxin per ampoule.  相似文献   

16.
何坎  刘怀琼 《生理学报》1990,42(6):591-594
大肠杆菌 O55B5内毒素在体外可抑制人血小板自发性聚集,并使血小板内 cAMP、钙调素明显增高,但对肾上腺素诱发的血小板聚集无作用,也不能引起血小板致密颗粒和α-颗粒的释放。此外还观察到内毒素组无血小板上清液中5-HT 含量减少。  相似文献   

17.
为研究多器官功能不全综合征(MODS)时肠道细菌微生态的变化以及G^-杆菌消长与肠道和血液中内毒素水平的关系,本实验选用SD大鼠,应用无菌Zymosan腹腔注射制备大鼠MODS模型,并对MODS大鼠肠道菌群进行定量分析,对门静脉和外周静脉血中的内毒以及肠道游离内毒素含量进行定量测定。结果发现,MODS状态下肠道细菌微生态发生明显变化,表现为肠杆菌和肠球菌等肠道内需氧菌的数量明显增多,双歧杆菌和乳酸  相似文献   

18.
牙髓紫卟啉菌内毒素对炎症性细胞因子的介导作用   总被引:2,自引:0,他引:2       下载免费PDF全文
牙髓紫叶琳菌ATCC35406是近年来新发现的重要致病性专性厌氧菌,采用改良酚-氯仿-石油醚法提取牙髓紫卟啉菌ATCC35406内毒素脂多糖,通过Kramer测定法、软琼脂细胞培养法以及胸腺细胞增殖法测定脂多糖的细胞生物学活性。结果显示:纯化脂多糖可不同程度地诱导小鼠模型生成肿瘤坏死因子(TNF)、集落刺激因子(CSF)和白介素-1(IL-1),并在一定范围内呈剂量依赖型,提示牙髓紫卟啉菌内毒素在动物模型和细胞模型中具有显著的细胞生物学和免疫学活性.  相似文献   

19.
Whole cell pertussis vaccine is still widely used in many countries. An International Standard is needed for its potency control. The Third International Standard for Pertussis Vaccine was prepared about 40 years ago and its replacement was recommended by the Expert Committee for Biological Standardisation (ECBS) of the WHO. Material in ampoules coded 94/532 was prepared as a candidate replacement and has been evaluated in international collaborative studies which consisted of two parts. The first part, to assess the suitability of the candidate standard by comparing it with the Second International Standard for Pertussis Vaccine (IS2) involved 14 laboratories in 11 countries. The second part to compare the candidate standard with the Third International Standard for Pertussis Vaccine (IS3) involved 16 laboratories in 14 countries. Since 1995 various other studies have included the international standards and the results of these are also considered in assessing likely continuity of the IU for potency of whole cell pertussis vaccine. The preparation in ampoules coded 94/532 was adopted by the WHO ECBS in October 2006 as the 4th International Standard for whole cell pertussis vaccine and assigned an activity of 40 IU per ampoule on the basis of the studies reported here.  相似文献   

20.
丽珠肠乐(回春生)对肝硬化的疗效观察   总被引:1,自引:0,他引:1  
丽珠肠乐(回春生)为双歧杆菌活菌制剂,给73例肝硬化失代期病人口服22~67天。治疗前后分别检测血内毒素含量及肝功能,观察其疗效。结果表明本制剂对肝硬化的疗效明显,总有效率为79.45%,其中内毒素水平治疗后明显下降,与治疗前比较,P<0.01,有效率为87.67%。肝功能各指标有不同程度的改善,有效率78.08%。说明回春生是当代最新的微生态调节剂。  相似文献   

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