用巨细胞病毒抗原致敏的冻干血球作间接血凝试验

本文报告用巨细胞病毒(CMV)抗原致敏的冻干绵羊红细胞(简称冻干血球)做间接血凝试验。用5％正常兔血清和10％蔗糖磷酸盐缓冲液作保护剂,将巨细胞病毒抗原致敏的绵羊红细胞进行真空冷冻干燥,制成了冻干血球。经反复检测发现,用含百万分之一Tween20、2％正常兔血清的磷酸缓冲液稀释冻干血球,可消除冻干过程中产生的非特异性凝集反应。所建立的方法重复性较好,特异性与ELISA相同,敏感性比CF高。     

病毒活疫苗冻干保护剂筛选研究

为提高冻干病毒性活疫苗的成品滴度和稳定性及提高疫苗生产的出品率,本研究通过对多种保护剂成分如明胶、山梨醇、蔗糖、乳糖、右旋糖苷、精氨酸等及其配比的大量反复筛选试验,已初步选定了数种可供选择并进一步优化完善的冻干保护剂配方。与现行冻干保护剂相比,其疫苗出品率在相同投入下可提高三倍。     

巨细胞病毒的免疫学研究进展

巨细胞病毒（ＣＭＶ）感染可引起机体的免疫功能降低，特别是细胞免疫。本文综述了ＣＭＶ对胸腺发育，对脾细胞、单核巨噬细胞、ＮＫ细胞、ＣＴＬ细胞的免疫调节、效应功能的影响。     

EB、巨细胞病毒

<正>现在一般用测定血清抗体价的方法诊断EB病毒和巨细胞病毒(CMV)感染症,在诊断CMV时同时由尿分离病毒(接种于人胎肺细胞,由细胞病变判断)。在感染初期,IgM抗体的出现具有特异诊断价值,但在初期感染之后便100%的呈现潜伏状。由于免疫抑制等宿主方面的原因常见病毒的再活动化。90%以上的日本人感染该二病毒,由健康人的唾液分离出EBV、尿液分离出CMV也不罕见。在AIDS(艾兹病)、器官移植等高度免疫抑制时,常常出现伴随EBV、CMV活动化的重笃感染。DNA诊断的优点是迅速和判断客观,最近建立了多聚酶链反应法(PCR),使大幅增加检测敏感度成为可能。但是对于EBV、CMV这样的在健康人就存在的病原体,既使检测敏感度增加到能检出微量病毒DNA的程度,也很难判定是否果真是病原体。本文介绍DNA诊断的现状及未来。各种检测方法的实例描述于CMV项。     

人类巨细胞病毒与人类肿瘤

人类巨细胞病毒（ＨＣＭＶ）感染能导致多种细胞生物学特性的改变,通过分子病毒学及分子生物学方法在数种人类恶性肿瘤组织中检出ＨＣＭＶＤＮＡ和（或）基因产物。ＨＣＭＶ基因产物可通过激活细胞内多种因子基因,刺激原癌基因表达,抑制抗癌基因产物功能等多种途径干扰细胞生长,分化的调控机制,诱导细胞发生恶性变,ＨＣＭＶ持续感染可以增加受感染细胞恶性特征的表达,大量实验结果证实了ＨＣＭＶ的致癌潜能,揭示了ＨＣＭＶ在     

大蒜中抗人巨细胞病毒成份的筛选

临床试用大蒜制剂预防和治疗人巨细胞病毒感染取得了明显效果。在此基础上我们应用细胞病变(CPE)抑制试验和空斑抑制试验,对大蒜中的抗人巨细胞病毒成份进行了初步筛选和比较,证实新鲜大蒜中存在多种抗该病毒的有效成份,其中至少包括大蒜新素(二丙烯三硫)和Ajoene类似物。     

人巨细胞病毒的分子生态学

近来我们不只一次的讨论过分子生态学,特别是病毒的分子生态学问题,并提出了病毒性疾病的发生,主要是由于有关的分子生态失调的论点。但都未涉及病毒微生态学或病毒分子生态学的基本含义。这里,有必要对之加以明确,然后才对人巨细胞病毒的分子生态学     

人巨细胞病毒抗原血症

人巨细胞病毒（ＨＣＭＶ）抗原血症试验是近年来报道的一种早期,快速诊断活动性ＨＣＭＶ感染的新方法。本文就其方法学,敏感性与特异性及实用价值作一综述。     

用热处理灭活冻干凝血因子浓缩物中的病毒

<正>冻干血浆制品的热处理已被用于降低感染病毒传播的危险,特别是那些能引起肝炎的病毒。当认识到血浆制品能传播AIDS HIV因子的病因时,美国国家血友病基金会的医学和科学顾问委员会和疾病控制中心推荐使用热处理的制品,以降低传播病毒的危险。使用不包括病毒灭活步骤的方法提取的凝血因子,在美国不再被批准。     

Preservation by lyophilization of a human intestinal microbiota: influence of the cultivation pH on the drying outcome and re-establishment ability

Faecal microbiota transplantation is an emerging medical concept for the treatment of gastrointestinal diseases. This concept, however, has disadvantages as low storability of stool and intensive donor screening. A solution to overcome these problems would be the preservation of an in vitro microbiota through freeze–drying. However, the influence of the entire preservation process, including cultivation and lyophilization, has not been assessed so far. In this study, the influences of the process steps cultivation, drying and re-cultivation were determined with cell count, production of metabolites, microbial composition and diversity in the system as evaluation criteria. All pH conditions resulted in stable, culturable communities after re-cultivation. Cell count, richness, diversity and microbial composition were affected by freeze–drying, but these effects were reversible and vanished during re-cultivation. Hence, the re-cultivated system did not differ from the system before drying. The metabolism, measured by short-chain fatty acids as indicators, showed slight changes due to natural dynamics. Consequently, the cultivation prior to drying was identified to have more influence than the drying itself on the preservation process and therefore the biggest potential for optimization. Hence, the highest similarity with the initial stool sample was obtained with pH 6.0 - 6.5 during cultivation.     

Long-term preservation of active luminous bacteria by lyophilization

A simple method for long-term preservation of luminous bacteria is described. Cells of Vibrio fischeri, Photobacterium leiognathi and four strains of P. phosphoreum were suspended in a protective medium of low ionic strength (1% NaCI) supplemented with 15% lactose and 2% soluble starch, and lyophilized. The freeze-dried preparations were sealed under vacuum and stored at 4°C. Luminous bacteria were resuscitated affer six months by adding 2% NaCl up to the original volume. The rehydrated cells exhibited 16-28% of initial bioluminescence so that they could be used for a microbial test of toxicity (the Microtox test). This method is also useful for maintaining luminous bacteria in strain collections.     

Cross-contamination during lyophilization

Cross-contamination during lyophilization was studied in two freeze-dryers. Suspensions of test organisms (Pseudomonas aeruginosa and Proteus mirabilis) sensitive to colistin and neomycin, respectively, were dispensed into vials, freeze-dried, and plated on an agar medium containing colistin or neomycin.In a small, chambered freeze-dryer, 0.8–3.3% cross-contamination occurred when each side of the tray had a different organism, and 8.3–13.3% when a cluster of vials in the middle was surrounded by vials with the other organism. Preliminary results in a larger freeze-dryer showed no shelf-to-shelf cross-contamination.Since the condenser port of the smaller freeze-dryer was underneath the shelf holding the vials during sublimation, and the larger freeze-dryer had a port in the rear wall of the chamber, cross-contamination may be dictated (at least partially) by this condition.     

A study of the catalase monomer produced by lyophilization

Lyophilization of Dounce and Mourtzikos beef liver catalase (Prep. Biochem. 11 (1981) 501-523) under specified conditions produced conformationally altered but not completely denatured catalase monomer which retained both significant catalatic activity and peroxidatic activity towards ethanol. The same lyophilization procedure used with Sigma Co. catalase produced a mixture of conformationally altered catalase monomer and conformationally altered tetramer which showed still higher catalatic and peroxidatic activities; this was attributed to the presence of the altered tetramer. The catalase monomer obtained by the use of Dounce and Mourtzikos catalase is completely reducible by dithionite, as shown by the two-banded spectrum of the reduced material, but apparently retains enough of its native conformation to show some enzymatic activity, since the fully denatured monomer shows no catalatic or peroxidatic activity towards ethanol. The conformationally altered catalase tetramer, which shows more enzymatic activity than the monomer, evidently retains a higher proportion of its native conformation than the monomer, but still appears to be fully reducible with dithionite. Horseradish peroxidase after reduction with dithionite shows spectral bands at positions close to those of reduced lyophilized catalase, but the relative band heights and contours are different. A possible explanation for the observed differences in lyophilization products depending on the starting material (Sigma Co. catalase versus catalase of Dounce and Mourtzikos) is presented.     

Improved preservation of human red blood cells by lyophilization

The lyophilization of human red blood cells has important implications for blood transfusion in clinical medicine. In this study, sugars, human serum albumin, polyvinylpyrrolidone, and dimethyl sulfoxide were used as protective reagents for the lyophilization of red blood cells. Freezing temperature, shelf temperature, and the rehydration conditions were optimized. The results showed that extracellular disaccharides, especially trehalose, did not increase the recovery of hemoglobin. However, when the concentration of human serum albumin was higher than 25%, it had a considerable protective effect on the recovery of lyophilized red blood cells; the cellular hemoglobin recovery was over 70%, which was significantly higher than that in the group without human serum albumin (P<0.01). As the concentration of polyvinylpyrrolidone was increased, the extent of vitrification also increased. But when the concentration of polyvinylpyrrolidone was over 40%, the resulting concentration of free hemoglobin was over 1g/L, which was significantly higher than that with 40% (P<0.01). When lyophilization was carried out after freezing at different temperatures, the recovery of cells and hemoglobin was 70-80% and there were no significant differences among the five groups. When the shelf temperature was higher than -30 degrees C, the samples were partly collapsed, but when the shelf temperature was lower than -30 degrees C, the recovery of cells in the -40 and -45 degrees C groups was significantly higher than in the -30 and -35 degrees C groups (P<0.05). The recovery of cells and hemoglobin after lyophilization and rehydration in solutions containing low concentrations of polymers was over 80%, which is significantly higher than the other groups (P<0.01). In addition, when the temperature was higher than 25 degrees C, the concentration of free hemoglobin was significantly lower than it was at 4 degrees C (P<0.01). In conclusion, our study showed the lyophilization of red blood cells is feasible. Disaccharides have no protective effect on lyophilized cells when they are only extracellular and extensive vitrification may be not beneficial. Although the recovery of cells after lyophilization and rehydration by our method was over 70%, the ultrastructure of the cells may be compromised and some hemolysis does still exist. Further research is required.