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1.
《Vaccine》2019,37(47):6987-6995
Vero cells are nowadays widely used in the production of human vaccines. They are considered as one of the most productive and flexible continuous cell lines available for vaccine manufacturing. However, these cells are anchorage dependent, which greatly complicates upstream processing and process scale-up. Moreover, there is a recognized need to reduce the costs of vaccine manufacturing to develop vaccines that are affordable worldwide. The use of cell lines adapted to suspension growth contributes to reach this objective.The current work describes the adaptation of Vero cells to suspension culture in different serum free media according to multiple protocols based on subsequent passages. The best one that relies on cell adaption to IPT-AFM an in-house developed animal component free medium was then chosen for further studies. Besides, as aggregates have been observed, the improvement of IPT-AFM composition and mechanical dissociation were also investigated.In addition to IPT-AFM, three chemically defined media (CD293, Hycell CHO and CD-U5) and two serum free media (293SFMII and SFM4CHO) were tested to set up a serum free culture of the suspension-adapted Vero cells (VeroS) in shake flasks. Cell density levels higher than 2 × 106 cells/mL were obtained in the assessed conditions. The results were comparable to those obtained in spinner culture of adherent Vero cells grown on Cytodex 1 microcarriers.Cell infection with LP-2061 rabies virus strain at an MOI (Multiplicity of Infection) of 0.1 and a cell density of 8 ± 0.5 × 105 cells/mL resulted in a virus titer higher than 107 FFU/mL in all media tested. Nevertheless, the highest titer equal to 5.2 ± 0.5 × 107 FFU/mL, was achieved in IPT-AFM containing a reduced amount of Ca++ and Mg++. Our results demonstrate the suitability of the obtained VeroS cells to produce rabies virus at a high titer, and pave the way to develop VeroS cells bioreactor process for rabies vaccine production. 相似文献
2.
瘙痒是皮肤科的一种常见症状,是多因素相互作用的结果,其发生受到中枢和外周机制的双重调控,但具体发生机制尚不十分清楚。近年来随着研究的不断深入,多种物质如组胺、乙酰胆碱、5-羟色胺、蛋白酶和蛋白酶相关受体、细胞因子、阿片样肽等介质在瘙痒产生过程中起重要作用,这些介质通过刺激C类神经纤维或直接与皮肤感觉神经纤维受体相结合来介导瘙痒。本文就将皮肤瘙痒的神经传导及传导介质作一综述。 相似文献
3.
雷波 《中国脊柱脊髓杂志》2006,(6)
通过对影响杆菌肽抑菌圈大小的各种因素的研究,从而得到提高地衣芽抱杆菌发酵杆菌肽的产量及测量的最佳效果。研究结果表明豆芽汁培养基发酵的杆菌肽产量最高,并且在豆芽汁中加糖量为2g/dL时,抑菌圈最大。管碟法测定时,培养基的厚度影响最为显著,下层厚度10mL,上层5mL最佳,上层培养基的酸碱度为7.0,指示菌的浓度在10^8cfu/mL时,抑菌圈最清晰,直径最大,平均直径为2.52cm。 相似文献
4.
5.
3种培养基体外培养人芽囊原虫的效果观察 总被引:1,自引:0,他引:1
目的 观察人芽囊原虫在 3种培养基中的生长繁殖情况 ,以探讨最佳的培养方法。 方法 从大学生粪便中分离人芽囊原虫 ,转种至 3种不同培养基 ,定时观察人芽囊原虫的生长繁殖情况 ,根据原虫密度评价培养效果。 结果培养 96h后 ,Locke’s鸡蛋血清 (LES)双相培养基中的人芽囊原虫密度最高 ,改良Jones单相液体培养基次之 ,Locke’s琼脂血清 (LAS)双相培养基原虫密度最低 ,差异有显著性 (P <0 .0 5 ) ;观察 3种培养基中的原虫密度高峰持续时间分别为 3 60h、96h和 72h ,最长存活时间分别为 5 5 2h、3 3 6h和 168h。 结论 Locke’s鸡蛋血清双相培养基较适用于人芽囊原虫体外增殖培养。 相似文献
6.
P. E. Langdon A. Swift & R. Budd 《Journal of intellectual disability research : JIDR》2006,50(11):828-836
Background The social climate of inpatient facilities is thought to be an important contributor to treatment outcome. However, little research has focused on this construct within secure forensic services for people with intellectual disabilities (ID). Therefore, the objective of this study was to investigate the social climate of two different types of secure units (‘low’ secure vs. ‘medium’ secure) contained within the same facility for offenders with ID. Two hypotheses were generated: (1) residents would rate the social climate of the whole facility in a more negative direction than staff, and (2) residents and staff would rate the social climate of the ‘low’ secure unit in a more positive direction than that of the ‘medium’ secure unit. Method Using a 2 (factor ‘Participant’ = Staff or Resident) × 2 (factor ‘Unit’ = ‘Low’ or ‘Medium’ Secure Unit) between‐subjects design, 18 residents and 37 staff members were recruited and completed the Correctional Institutions Environment Scale (CIES), a measure of social climate. Results Residents tended to rate the units in a more positive direction than staff on some sub‐scales. Participants rated the ‘low’ secure unit in a more positive direction than the ‘medium’ secure unit on two sub‐scales of the CIES. However, on selected sub‐scales there were differences. The findings of this study suggest that the CIES may be a valid instrument for use within forensic services for people with ID, and further suggests that residents and staff have different perceptions of the shared social climate, which may have implications for service development. 相似文献
7.
目的 :通过分析比较结肠扫描不同充填剂与不同体位的方法 ,探讨出最佳充填剂与最佳体位以提高结肠 CT扫描质量。方法 :分别对 4 0例结肠 CT扫描病人采用不同的充填剂 ,与不同的体位 ,评价不同的充填剂与不同体位的优缺点。结果 :水作为充填剂组病灶显示情况明显优于泛影萄胺组且伪影少 ,选择不同体位组图像质量也明显优于常规体位组。结论 :结肠 CT扫描时应首选水作为充填剂 ,根据病变不同选择不同的体位 ,有利于图像质量的提高 相似文献
8.
以髓系(HL-60)与淋系(Molt-4)细胞为观察对象,用细胞计数、细胞集落培养、台酚蓝拒染及溴化二甲噻唑二苯四唑试验为观察手段,研究胎肌条件培养液(FMCM)对白血病细胞的影响.实验标本分为4组:①对照组.②20%FMCM处理组.③阿糖胞苷(Ara-C,1×10~(-7)M/L)处理组.④混合处理组(经FMCM与Ara-C二者的处理).发现:①FMCM对两个细胞株均无明显的直接作用.②当HL-60细胞经FMCM预处理或在用Ara-C处理同时加入FMCM,Ara-C对其抑制作用可为FMCM加强,已受Ara-C抑制的HL-60细胞则无此现象.③Ara-C对Molt-4的抑制作用不受FMCM的影响.由此而初步认为:①FMCM对白血病细胞似无明显直接作用.②某些(非全部)白血病细胞对Ara-C的敏感性可为FMCM加强.③在己受抑制的细胞中不呈现这种致敏现象.①提示FMCM有可能用于白血病临床治疗. 相似文献
9.
Human recombinant erythropoietin directly stimulates B cell immunoglobulin production and proliferation in serum-free medium.
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H Kimata A Yoshida C Ishioka S Masuda R Sasaki H Mikawa 《Clinical and experimental immunology》1991,85(1):151-156
The effect of human recombinant erythropoietin (Epo) on B cell responses was studied in a serum-free medium. Epo enhanced IgM production and thymidine uptake by a human IgM-producing lymphoblastoid cell line, CBL. This effect was specific to Epo since enhancement was blocked by anti-Epo antibody but not by control antibody. Among the various cytokines, interleukin-4 (IL-4) enhanced IgM production and thymidine uptake while IL-6 enhanced IgM production without affecting thymidine uptake. In contrast, other cytokines including IL-1 beta, IL-2, IL-5, interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), or granulocyte/macrophage colony-stimulating factor (GM-CSF) were without effect. However, the enhancing effect of Epo is different from that of IL-4 or IL-6, since Epo effect was not blocked by anti-IL-4 antibody or anti-IL-6 antibody. Moreover, specific binding of Epo was detected on CBL cells. Epo also enhanced immunoglobulin (IgG, IgM and IgA) production and thymidine uptake by purified tonsil small resting B cells stimulated by Staphylococcus aureus Cowan strain I (SAC) or by large activated B cells. In contrast, Epo had no effect on unstimulated small resting B cells. These results indicate that Epo could directly stimulate activated and differentiated B cells and could enhance B cell immunoglobulin production and proliferation. 相似文献
10.