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1.
Jennifer Dumont Don Euwart Baisong Mei Scott Estes Rashmi Kshirsagar 《Critical reviews in biotechnology》2016,36(6):1110-1122
Biotherapeutic proteins represent a mainstay of treatment for a multitude of conditions, for example, autoimmune disorders, hematologic disorders, hormonal dysregulation, cancers, infectious diseases and genetic disorders. The technologies behind their production have changed substantially since biotherapeutic proteins were first approved in the 1980s. Although most biotherapeutic proteins developed to date have been produced using the mammalian Chinese hamster ovary and murine myeloma (NS0, Sp2/0) cell lines, there has been a recent shift toward the use of human cell lines. One of the most important advantages of using human cell lines for protein production is the greater likelihood that the resulting recombinant protein will bear post-translational modifications (PTMs) that are consistent with those seen on endogenous human proteins. Although other mammalian cell lines can produce PTMs similar to human cells, they also produce non-human PTMs, such as galactose-α1,3-galactose and N-glycolylneuraminic acid, which are potentially immunogenic. In addition, human cell lines are grown easily in a serum-free suspension culture, reproduce rapidly and have efficient protein production. A possible disadvantage of using human cell lines is the potential for human-specific viral contamination, although this risk can be mitigated with multiple viral inactivation or clearance steps. In addition, while human cell lines are currently widely used for biopharmaceutical research, vaccine production and production of some licensed protein therapeutics, there is a relative paucity of clinical experience with human cell lines because they have only recently begun to be used for the manufacture of proteins (compared with other types of cell lines). With additional research investment, human cell lines may be further optimized for routine commercial production of a broader range of biotherapeutic proteins. 相似文献
2.
Risks and benefit evaluation for controlled human infection studies, where healthy volunteers are deliberately exposed to infectious agents to evaluate vaccine efficacy, should be explicit, systematic, thorough, and non-arbitrary. Decision analysis promotes these qualities using four steps: (1) determining explicit criteria and measures for evaluation, (2) identifying alternatives to the study, (3) defining the models used to estimate the measures for each alternative, and (4) running the models to produce the estimates and compare the alternatives. In this paper, we describe how decision analysis might be applied by funders and regulators, as well as by others contemplating the use of novel controlled human infection studies for vaccine development and evaluation. 相似文献
3.
Oral vaccines may contain adjuvants which might elicit allergies against dietary proteins. Four antigens were used to measure such an effect--ovalbumin, soya bean protein, lactalbumin and gluten. Neither guinea pigs nor mice showed IgE responses after oral administration of adjuvanted vaccines containing lactalbumin and gluten. No IgE responses were detected in mice with any of these antigens after oral immunization, but, in the guinea pig, nine out of 18 animals reacted to either ovalbumin or soya bean protein and none reacted to lactalbumin and gluten. It is concluded that the risk of allergy induction against normal dietary proteins is low but such tests should be applied to potential adjuvanted oral vaccines to measure any possible contraindication, especially with atopic individuals. 相似文献
4.
Kenneth Lundström 《FEMS microbiology letters》1984,23(1):65-70
Abstract The molecularly cloned gene encoding the vesicular stomatitis virus (VSV) membrane glycoprotein G was modified and joined to a Bacillus subtilis secretion vector constructed from the plasmid pUB110 and containing the promoter and signal sequence regions of the α-amylase (a secretory protein) gene from Bacillus amyloliquefaciens . The regions encoding the NH2 -terminal signal peptide and the COOH-terminal hydrophobic transmembrane domains of the VSV gene were deleted to facilitate the secretion of the G protein in soluble form. The truncated G protein was found to be expressed in B. subtilis . The expression level was low, probably due to rapid proteolytic degradation of the protein and, contrary to what was expected, almost all of the protein remained cell-associated. 相似文献
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7.
Babar Maqbool Yong Wang Xuemei Cui Shanshan He Ran Guan Shenghao Wang Yuemin Wang Songhua Hu 《Microbiology and immunology》2019,63(7):269-279
Pseudorabies, a herpesvirus infection, is mainly controlled by using attenuated live vaccines. In this study, the effect of ginseng stem and leaf saponins (GSLS) in combination with selenium (Se; in the form of sodium selenite) on vaccination against attenuated pseudorabies virus (aPrV) was evaluated. It was found that GSLS and Se have an adjuvant effect and that a combination of GSLS and Se stimulates significantly enhanced immune responses than does GSLS or Se alone. Following oral administration of GSLS, mice immunized with an attenuated PrV vaccine diluted in Se‐containing physiological saline solution (PSS) provoked a significantly stronger gB‐specific serum antibodies response (IgG, IgG1 and IgG2a), enhanced lymphocyte proliferation and cytolytic activity of NK cells, along with higher production of cytokines (IFN‐γ, IL‐12, IL‐5 and IL‐10) by splenocytes. Notably, the combination of GSLS and Se conferred a much higher resistance to fPrV challenge after immunization of the mice with aPrV vaccine. This study offers convincing experimental evidence that an injection of Se with oral GSLS is a promising adjuvant combination that improves the efficacy of vaccination against PrV and deserves further study regarding improvement of responses to other animal vaccines. 相似文献
8.
To enable large-scale antibody production, the creation of a stable, high producer cell line is essential. This process often takes longer than 6 months using standard limited dilution techniques and is very labor intensive. The use of a tri-cistronic vector expressing green fluorescent protein (GFP) and both antibody chains, separated by a GT2A peptide sequence, allows expression of all proteins under a single promotor in equimolar ratios. By combining the advantages of 2A peptide cleavage and single cell sorting, a chimeric antibody-antigen fusion protein that contained the variable domains of mouse IgG with a porcine IgA constant domain fused to the FedF antigen could be produced in CHO-K1 cells. After transfection, a strong correlation was found between antibody production and GFP expression (r = 0.69) using image analysis of formed monolayer patches. This enables the rapid selection of GFP-positive clones using automated image analysis for the selection of high producer clones. This vector design allowed the rapid selection of high producer clones within a time-frame of 4 weeks after transfection. The highest producing clone had a specific antibody productivity of 2.32 pg/cell/day. Concentrations of 34 mg/L were obtained using shake-flask batch culture. The produced recombinant antibody showed stable expression, binding and minimal degradation. In the future, this antibody will be assessed for its effectiveness as an oral vaccine antigen. 相似文献
9.
Chang Shin Yoon Eun Gyu Lee Young Seek Lee Il Yup Chung 《Biotechnology and Bioprocess Engineering》1997,2(2):86-89
Epidermal growth factor (EGF) known as a urgastrone is a powerful mitogen with a wide variety of possibilities for medical
usages. A mature EGF coding region was isolated from human prepro-EGF sequence by a conventional PCR and cloned into pQE vector
in which the gene product was supposed to be expressed with 6×His tag for the subsequent purification. The recombinant mature
EGF was expressed in M15[Rep4], anEscherichia coli host strain, in amount of 30–40% of total proteins present inE. coli extract by the addition of isopropylthio-β-galactopyranoside (IPTG). The recombinant EGF purified using a Ni2+-NTA affinity column chromatography was active in its ability to induce phosphorylation on tyrosine residues of several substrate
proteins when murine NIH3T3 and human MRC-5 fibroblast cells were stimulated with it. This work may provide the basic technology
and information for the production of recombinant EGF. 相似文献
10.