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Li BL, Wang JR, Liu XY, Lu JS, Wang R, Du P, Yu S, Pang XB, Yu YZ, Yang ZX. Tetanus toxin and botulinum neurotoxin-derived fusion molecules are effective bivalent vaccines. Appl Microbiol Biotechnol 2023; 107:7197-7211. [PMID: 37741939 DOI: 10.1007/s00253-023-12796-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/06/2023] [Accepted: 09/13/2023] [Indexed: 09/25/2023]
Abstract
Tetanus toxin (TeNT) and botulinum neurotoxins (BoNTs) are neuroprotein toxins, with the latter being the most toxic known protein. They are structurally similar and contain three functional domains: an N-terminal catalytic domain (light chain), an internal heavy-chain translocation domain (HN domain), and a C-terminal heavy chain receptor binding domain (Hc domain or RBD). In this study, fusion functional domain molecules consisting of the TeNT RBD (THc) and the BoNT/A RBD (AHc) (i.e., THc-Linker-AHc and AHc-Linker-THc) were designed, prepared, and identified. The interaction of each Hc domain and the ganglioside receptor (GT1b) or the receptor synaptic vesicle glycoprotein 2 (SV2) was explored in vitro. Their immune response characteristics and protective efficacy were investigated in animal models. The recombinant THc-linker-AHc and AHc-linker-THc proteins with the binding activity had the correct size and structure, thus representing novel subunit vaccines. THc-linker-AHc and AHc-linker-THc induced high levels of specific neutralizing antibodies, and showed strong immune protective efficacy against both toxins. The high antibody titers against the two novel fusion domain molecules and against individual THc and AHc suggested that the THc and AHc domains, as antigens in the fusion functional domain molecules, do not interact with each other and retain their full key epitopes responsible for inducing neutralizing antibodies. Thus, the recombinant THc-linker-AHc and AHc-linker-THc molecules are strong and effective bivalent biotoxin vaccines, protecting against two biotoxins simultaneously. Our experimental design will be valuable to develop recombinant double-RBD fusion molecules as potent bivalent subunit vaccines against bio-toxins. KEY POINTS: • Double-RBD fusion molecules from two toxins had the correct structure and activity. • THc-linker-AHc and AHc-linker-THc efficiently protected against both biotoxins. • Such bivalent biotoxin vaccines based on the RBD are a valuable experimental design.
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Affiliation(s)
- Bo-Lin Li
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Jing-Rong Wang
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Xu-Yang Liu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
- Pharmaceutical College, Henan University, Kaifeng, 475001, China
| | - Jian-Sheng Lu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Rong Wang
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Peng Du
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Shuo Yu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng, 475001, China.
| | - Yun-Zhou Yu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China.
| | - Zhi-Xin Yang
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, 20 Dongdajie Street, Beijing, 100071, China.
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Wang R, Guo J, Lu J, Du P, Zhang J, Yu Y, Chen L, Xiong Z, Xiang Y, Ni X, Xu J, Yang Z. A potential broad-spectrum neutralizing antibody against Betacoronavirus. J Med Virol 2023; 95:e29252. [PMID: 38078658 DOI: 10.1002/jmv.29252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/13/2023] [Accepted: 11/10/2023] [Indexed: 12/18/2023]
Abstract
Three pandemics caused by human Betacoronavirus had broken out in the past two decades. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was one of the novel epidemic strains which caused the third pandemic, coronavirus disease 2019 (COVID-19), a global public health crisis. So far, more than millions of people have been infected. Considering the public health and economic impact of Betacoronavirus pandemic, drugs with broad-spectrum activity against these coronaviruses are urgently needed. In this study, two monoclonal antibodies targeting SARS-CoV-2 spike protein receptor-binding domain (RBD) with good neutralizing activity were used to construct a novel immunoglobulin-like bispecific antibody BI31. The neutralizing effect of BI31 against the pseudovirus and the authentic virus is better than that of its parent antibodies alone and in combination. What surprised us most was that the newly constructed bispecific antibody also had the neutralizing activity against SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) that the parent antibodies did not have. These suggested that the BI31 can not only be developed as a therapeutic drug against COVID-19 but it could also become a broad-spectrum therapeutic antibody against Betacoronavirus.
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Affiliation(s)
- Rong Wang
- Beijing Institute of Biotechnology, Beijing, China
| | - Jiazheng Guo
- Beijing Institute of Biotechnology, Beijing, China
| | - Jiansheng Lu
- Beijing Institute of Biotechnology, Beijing, China
| | - Peng Du
- Beijing Institute of Biotechnology, Beijing, China
| | - Jun Zhang
- Beijing Institute of Biotechnology, Beijing, China
| | - YunZhou Yu
- Beijing Institute of Biotechnology, Beijing, China
| | - Lei Chen
- Beijing Institute of Biotechnology, Beijing, China
| | | | | | - Xiaodan Ni
- Shuimu BioSciences Co., Ltd, Beijing, China
| | - Junjie Xu
- Beijing Institute of Biotechnology, Beijing, China
| | - Zhixin Yang
- Beijing Institute of Biotechnology, Beijing, China
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Liu XY, Wei DK, Li ZY, Lu JS, Xie XM, Yu YZ, Pang XB. Immunogenicity and immunoprotection of the functional TL-HN fragment derived from tetanus toxin. Vaccine 2023:S0264-410X(23)01102-7. [PMID: 37816654 DOI: 10.1016/j.vaccine.2023.09.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 09/11/2023] [Accepted: 09/18/2023] [Indexed: 10/12/2023]
Abstract
Tetanus toxin (TeNT) is a protein toxin produced by Clostridium tetani bacteria, which causes hyperreflexia and rhabdomyolysis by spastic paralysis. Like botulinum neurotoxin, TeNT comprises a heavy chain (HC) and a light chain (LC) linked via an interchain disulfide bond, which include the following three functional domains: a receptor-binding domain (Hc), a translocation domain (HN), and a catalytic domain (LC). Herein, we produced and characterized three functional domains of TeNT and three types of TeNT-derived L-HN fragments (TL-HN, TL-GS-HN and TL-2A-HN), which contained L and HN domains but lacked the Hc domain. The immunological effects of these different functional domains or fragments of TeNT were explored in an animal model. Our investigations showed the TL-HN functional fragment provided the best immunoprotection among all the TeNT functional domains. The TL-HN fragment, as a protective antigen, induced the highest levels of neutralizing antibodies, indicating that it might contain some crucial epitopes. Further experiments revealed that the protective effect of TL-HN was superior to that of the THc, TL, or THN fragments, either individually or in combination. Therefore, the TL-HN fragment exerts an important function in immune protection against tetanus toxin, providing a good basis for the development of TeNT vaccines or antibodies, and could serve as a promising subunit vaccine to replace THc or tetanus toxoid (TT).
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Affiliation(s)
- Xu-Yang Liu
- Pharmaceutical College, Henan University, Kaifeng 475001, China; Beijing Institute of Biotechnology, Beijing 100071, China
| | - Dong-Kui Wei
- Pharmaceutical College, Henan University, Kaifeng 475001, China; Beijing Institute of Biotechnology, Beijing 100071, China
| | - Zhi-Ying Li
- Pharmaceutical College, Henan University, Kaifeng 475001, China; Beijing Institute of Biotechnology, Beijing 100071, China
| | - Jian-Sheng Lu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Xin-Mei Xie
- Pharmaceutical College, Henan University, Kaifeng 475001, China.
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing 100071, China.
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng 475001, China.
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Tan X, Zhang CC, Lu JS, Li ZY, Li BL, Liu XY, Yu YZ, Xu Q. Biology activity and characterization of the functional L-HN fragment derivative of botulinum neurotoxin serotype E. Anaerobe 2023; 82:102764. [PMID: 37479022 DOI: 10.1016/j.anaerobe.2023.102764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/23/2023]
Abstract
OBJECTIVES The mature botulinum neurotoxin (BoNT) is a long peptide chain consisting of a light chain (L) and a heavy chain (H) linked by a disulfide bond, where the heavy chain is divided into a translocation domain and an acceptor binding domain (Hc). In this study, we further explored the biology activity and characteristics of recombinant L-HN fragment (EL-HN) composed of the L and HN domains of BoNT/E in vivo and in vitro. METHODS Neurotoxicity of L-HN fragments from botulinum neurotoxins was assessed in mice. Cleavage of dichain EL-HN in vitro and in neuro-2a cells was assessed and compared with that of single chain EL-HN. Interaction of HN domain and the receptor synaptic vesicle glycoprotein 2C (SV2C) was explored in vitro and in neuro-2a cells only expressing SV2C. RESULTS We found that the 50% mouse lethal dose of the nicked dichain EL-HN fragment (EL-HN-DC) was 0.5 μg and its neurotoxicity was the highest among the L-HN's of the four serotypes of BoNT (A/B/E/F). The cleavage efficiency of EL-HN-DC toward synaptosome associated protein 25 (SNAP25) in vitro was 3-fold higher than that of the single chain at the cellular level, and showed 200-fold higher animal toxicity. The EL-HN-DC fragment might enter neuro-2a cells via binding to SV2C to efficiently cleave SNAP25. CONCLUSIONS The EL-HN fragment showed good biological activities in vivo and in vitro, and could be used as a drug screening model and to further explore the molecular mechanism of its transmembrane transport.
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Affiliation(s)
- Xiao Tan
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, 100044, China; Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Cong-Cong Zhang
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, 100044, China
| | - Jian-Sheng Lu
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Zhi-Ying Li
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Bo-Lin Li
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Xu-Yang Liu
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, 100071, China.
| | - Qing Xu
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, 100044, China.
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Shi DY, Lu JS, Mao YY, Liu FJ, Wang R, Du P, Yu S, Yu YZ, Yang ZX. Characterization of a novel tetravalent botulism antitoxin based on receptor-binding domain of BoNTs. Appl Microbiol Biotechnol 2023; 107:3205-3216. [PMID: 37058230 PMCID: PMC10102682 DOI: 10.1007/s00253-023-12515-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/27/2023] [Accepted: 03/31/2023] [Indexed: 04/15/2023]
Abstract
Botulinum neurotoxin (BoNTs; serotypes A, B, E, and F) cause botulism disease in humans, which could be effectively treated using antitoxins. Herein, we established a novel receptor-binding domain (RBD)-based antitoxin using recombinant C terminal heavy chain (Hc) domains of BoNTs as immunogens. Immunization of horses with these recombinant Hc domains allowed the purification and digestion of IgGs from hyper-immune sera to produce high-quality and high-efficiency monovalent botulism antitoxin F(ab')2 against each BoNT (M-BATs). However, these M-BATs could not bind or neutralize other serotypes of BoNTs, and that there were no cross-protective effects among these M-BATs. This suggested the need to prepare tetravalent antitoxins to neutralize the four BoNTs simultaneously. Thus, these M-BATs were formulated into a novel tetravalent botulism antitoxin (T-BAT), in which a 10-ml volume contained 10000 IU of BoNT/A and 5000 IU of BoNT/B, BoNT/E, and BoNT/F antitoxins. The novel antitoxin preparation could prevent and treat the four mixed botulinum neurotoxins simultaneously in vivo, representing strong efficacy in an animal poisoning model. Moreover, these antibodies in T-BAT could bind the RBD, whereas conventional antitoxins based on inactivated toxins mainly bind the light chain or heavy chain translocation domain (HN) and weakly bind the important RBD in current experimental conditions. The high levels of RBD-specific novel antitoxins can efficiently bind the RBD and neutralize natural or recombinant toxins containing this RBD. The findings of the present study experimentally support the use of RBD-specific antitoxins to treat BoNT serotype A, B, E, and F-mediated botulism. This study demonstrated the concept of developing potent novel multivalent antitoxins against all BoNTs or other toxins, using the RBD of these toxins as an alternative antigen to inactivated toxins. KEY POINTS: • Antitoxins based on the receptor-binding domains of botulinum neurotoxins were made. • Novel antitoxin binds RBD; traditional antitoxin mainly binds light chain or HN domain. • A tetravalent antitoxin could prevent and treat the four mixed neurotoxins in vivo.
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Affiliation(s)
- Dan-Yang Shi
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
- Tianjin Institute of Environmental & Operational Medicine, Tianjin, 300050, China
| | - Jian-Sheng Lu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Yun-Yun Mao
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Fu-Jia Liu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Rong Wang
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Peng Du
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Shuo Yu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Yun-Zhou Yu
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China.
| | - Zhi-Xin Yang
- Laboratory of Advanced Biotechnology, Beijing Institute of Biotechnology, Beijing, 100071, China.
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Shi DY, Liu FJ, Li ZY, Mao YY, Lu JS, Wang R, Pang XB, Yu YZ, Yang ZX. Development and evaluation of a tetravalent botulinum vaccine. Hum Vaccin Immunother 2022; 18:2048621. [PMID: 35435814 PMCID: PMC9196761 DOI: 10.1080/21645515.2022.2048621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are the most toxic known proteins. Naturally occurring botulism in humans is caused by botulinum serotypes A, B, E, and F. Vaccination is an effective strategy to prevent botulism. In this study, a tetravalent botulinum vaccine (TBV) that can prevent serotypes A, B, E, and F was developed using the C-terminal receptor-binding domain of BoNT (Hc) as an antigen. To develop a suitable vaccine formulation, in vitro binding experiments of antigens and aluminum adjuvant in different buffers, and in vivo experiments of TBV at different antigen concentrations, were conducted. Our results showed that the optimal vaccine formulation buffer was a pH 6.0 phosphate buffer, and the suitable antigen concentration was 40 or 80 µg/ml of each antigen. A pilot-scale TBV was then prepared and evaluated for immunogenicity and stability. The results showed that TBV could elicit strong protective efficacy against each BoNT in mice, and remain effective after two years of storage at 4ºC, indicating that the preparation was stable and highly effective. Adsorption experiments also showed that the antigens could be well adsorbed by the aluminum adjuvant after 2 years of storage. Our results provide valuable experimental data supporting the development of a tetravalent botulinum vaccine, which is a promising candidate for the prevention of botulinum serotypes A, B, E, and F.
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Affiliation(s)
- Dan-Yang Shi
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.,Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, Tianjin, China
| | - Fu-Jia Liu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.,Pharmaceutical College, Henan University, Kaifeng, China
| | - Zhi-Ying Li
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.,Pharmaceutical College, Henan University, Kaifeng, China
| | - Yun-Yun Mao
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Jian-Sheng Lu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Rong Wang
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng, China
| | - Yun-Zhou Yu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Zhi-Xin Yang
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
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Lyu WH, Xia F, Zhou CS, Huang M, Ding WW, Zhang S, Liu F, Ma JC, Li XL, Yu YZ, Zhang LJ, Lu GM. [Application of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients]. Zhonghua Yi Xue Za Zhi 2021; 101:481-486. [PMID: 33631892 DOI: 10.3760/cma.j.cn112137-20201117-03123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the diagnostic efficacy and potential application value of deep learning-based chest CT auxiliary diagnosis system in emergency trauma patients. Methods: A total of 403 patients, including 254 males and 149 females aged from 16 to 100 (50±19) years, who received emergency treatment for trauma and chest CT examination in the Eastern Theater General Hospital from September 2019 to November 2019 were retrospectively analyzed. Dr. Wise Lung Analyzer's chest CT auxiliary diagnosis system was applied to detect 5 types of injuries, including pneumothorax, pleural effusion/hemothorax, pulmonary contusion (shown as consolidation and ground glass opacity), rib fractures, and other fractures (including thoracic vertebrae, sternum, scapula and clavicle, etc.) and 6 other abnormalities (bullae, emphysema, pulmonary nodules, stripe, reticulation, pleural thickening). The diagnostic reference standards were labeled by two radiologists independently. The sensitivity and specificity of the auxiliary diagnosis system were evaluated. The imaging diagnostic reports were compared with the results of the auxiliary diagnosis system, and the diagnostic consistency between the two was calculated by using the Kappa test. Results: According to the reference standards, among the 403 patients, 29 were pneumothorax, 75 were pleural effusion/hemothorax, 131 were pulmonary contusion, 124 were rib fractures, and 63 were other fractures. The sensitivity and specificity of the auxiliary diagnosis system for detection of pneumothorax, pleural effusion/hemothorax, rib fractures, and other fractures were 96.6%, 97.6%, 80.0%, 99.7%, 99.2%, 83.9%, 84.1%, and 99.7%, respectively. The sensitivity of detecting lung contusion was 97.7%. There was a high consistency between the auxiliary diagnosis system and imaging diagnosis in the diagnosis of injuries, in which the kappa values of pneumothorax, pleural effusion, rib fracture and other fractures were 0.783, 0.821, 0.706 and 0.813, respectively (all P<0.001). Two cases of pneumothorax, three cases of pleural effusion/hemothorax, nine cases of rib fractures, and six cases of other fractures missed by imaging diagnosis were all detected by the auxiliary diagnosis system. The detection sensitivity of the auxiliary diagnosis system was higher for emphysema, pulmonary nodules and stripe (all>85%), but lower for bullae, reticulation and pleural thickening. Conclusions: The deep learning-based chest CT auxiliary diagnosis system could effectively assist chest CT to detect injuries in emergency trauma patients, which was expected to optimize the clinical workflow.
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Affiliation(s)
- W H Lyu
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
| | - F Xia
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
| | - C S Zhou
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
| | - M Huang
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
| | - W W Ding
- Department of General Surgery, Jinling Hospital, Southern Medical University, Nanjing 210002, China
| | - S Zhang
- Deepwise AI Lab, Deepwise Inc., Beijing 100080, China
| | - F Liu
- Deepwise AI Lab, Deepwise Inc., Beijing 100080, China
| | - J C Ma
- Deepwise AI Lab, Deepwise Inc., Beijing 100080, China
| | - X L Li
- Deepwise AI Lab, Deepwise Inc., Beijing 100080, China
| | - Y Z Yu
- Deepwise AI Lab, Deepwise Inc., Beijing 100080, China
| | - L J Zhang
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
| | - G M Lu
- Department of Medical Imaging, Jinling Hospital, the First School of Clinical Medicine, Southern Medical University, Nanjing, 210002, China
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Li Z, Lu JS, Liu S, Wang R, Xu Q, Yu YZ, Yang ZX. Recombinant L-HN Fusion Antigen Derived from the L and HN Domains of Botulinum Neurotoxin B Stimulates a Protective Antibody Response Against Active Neurotoxin. Neurotox Res 2021; 39:1044-1053. [PMID: 33616873 DOI: 10.1007/s12640-021-00337-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 01/04/2023]
Abstract
Botulinum neurotoxin (BoNT) is a neurotoxin produced by Clostridium botulinum in an anaerobic environment. BoNT is the most toxic protein among bacteria, animals, plants, and chemical substances reported to date. BoNTs are 150 kDa proteins composed of three major functional domains: catalytic (L domain, 50 kDa), translocation (HN domain, 50 kDa), and receptor-binding (Hc domain, 50 kDa) domains. Most studies have focused on the use of the Hc domain as an antigen because it is capable of generating robust protective immunity and contains some functional neutralizing epitopes. In the present study, we produced and characterized a recombinant L-HN fusion fragment of the parent BoNT/B (BL-HN) composed of L and HN domains with a deletion in the Hc domain (BHc). When the BL-HN protein was expressed in E. coli, it retained its stable structure and antigenicity. As a vaccine antigen, the recombinant BL-HN protein was found to induce sufficient protection against native BoNT/B in a mouse model. The BL-HN subunit vaccine could also induce a strong humoral immune response and generate sufficient neutralizing antibodies in immunized mice. Therefore, BL-HN may retain the native neurotoxin structure and critical epitopes responsible for inducing serum neutralizing antibodies. Studies of the dose-dependent immunoprotective effects further confirmed that the BL-HN antigen could provide potent protective immunity. This finding suggests that BL-HN can play an important role in immune protection against BoNT/B. Therefore, the BL-HN fusion fragment provides an excellent platform for the design of recombinant botulinum vaccines and neutralizing antibodies.
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Affiliation(s)
- Zhen Li
- Beijing Institute of Biotechnology, Beijing, 100071, China.,Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, 100044, China
| | - Jian-Sheng Lu
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Shan Liu
- PLA Rocket Force Characteristic Medical Center, Beijing, 100088, China
| | - Rong Wang
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Qing Xu
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, 100044, China
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, 100071, China.
| | - Zhi-Xin Yang
- Beijing Institute of Biotechnology, Beijing, 100071, China.
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9
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Liu FJ, Shi DY, Li ZY, Lu JS, Wang R, Pang XB, Yang ZX, Yu YZ. Evaluation of a recombinant tetanus toxin subunit vaccine. Toxicon 2020; 187:75-81. [PMID: 32889026 DOI: 10.1016/j.toxicon.2020.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 10/23/2022]
Abstract
Tetanus is an acute, fatal disease caused by exotoxin produced by Clostridium tetani. The current vaccine against tetanus is based on inactivated tetanus toxin (TeNT). To develop a recombinant TeNT vaccine suitable for replacement of full-length tetanus toxoid (TT) vaccine for use in humans, a recombinant non-tagged isoform of the Hc domain of the tetanus toxin (THc) was expressed in Escherichia coli and purified by sequential chromatography steps. The immunogenicity and protective effect of the THc antigen were explored and compared with those of TT in Balb/c mice. The THc-based subunit vaccine provided complete protection against TeNT challenge following a high dosage as a toxoid vaccine. While the anti-THc and neutralising antibody titres were higher for the THc-based vaccine than the TT vaccine because protective epitopes are located on the THc domain. Frequency- and dose-dependent immunoprotection were also observed in THc-immunised mice. Mice immunised with one injection of 1 μg or 4 μg THc antigen were completely protected against 102 or 103 50% mouse lethal dose (LD50) of TeNT, respectively. Furthermore, the THc protein was found to recognise and bind to ganglioside GT1b in a dose-dependent manner, and anti-THc sera antibodies also inhibited binding between THc and GT1b. Antigen on the form of recombinant non-tagged THc domain expressed in E. coli achieved strong immunoprotective potency, suggesting that it could be developed into a candidate subunit vaccine against tetanus as an alternative to the current TT vaccine.
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Affiliation(s)
- Fu-Jia Liu
- Beijing Institute of Biotechnology, Beijing, 100071, China; Pharmaceutical College, Henan University, Kaifeng, 475001, China
| | - Dan-Yang Shi
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Zhi-Ying Li
- Beijing Institute of Biotechnology, Beijing, 100071, China; Pharmaceutical College, Henan University, Kaifeng, 475001, China
| | - Jian-Sheng Lu
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Rong Wang
- Beijing Institute of Biotechnology, Beijing, 100071, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng, 475001, China.
| | - Zhi-Xin Yang
- Beijing Institute of Biotechnology, Beijing, 100071, China.
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, 100071, China.
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10
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Jiang H, Lv DJ, Song XL, Wang C, Yu YZ, Zhao SC. Upregulated circZMIZ1 promotes the proliferation of prostate cancer cells and is a valuable marker in plasma. Neoplasma 2019; 67:68-77. [PMID: 31686520 DOI: 10.4149/neo_2019_190213n116] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/11/2019] [Indexed: 11/08/2022]
Abstract
Increasing evidences have proved that circular RNAs (circRNAs), identified as a specific kind of non-coding RNAs, play a potential critical role in tumorigenesis including prostate cancer. However, the function of circRNAs in human prostate cancer remain largely unknown. In this study, we demonstrated that the expression of circZMIZ1 was higher in plasma of human prostate cancer than the paired benign prostatic hyperplasia (BPH) patients' plasma. Moreover, in cultured prostate cancer cells, knockdown of circZMIZ1 inhibited cell proliferation and caused cell cycle arrest at G1. Mechanistically, we also showed that circZMIZ1 could increase the expression of androgen receptor (AR) and androgen receptor splice variant 7 (AR-V7), which may be partly contributed to the occurrence and development of prostate cancer. In conclusion, these results revealed that circZMIZ1 might serve as a novel biomarker and a treatment target for prostate cancer treatment.
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Affiliation(s)
- H Jiang
- Department of Urology, Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - D J Lv
- Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China.,Guangdong Key Laboratory of Urology, Guangzhou Institute of Urology, Guangzhou, China
| | - X L Song
- Department of Radiation Oncology, Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China
| | - C Wang
- Department of Urology, Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Y Z Yu
- Department of Urology, Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - S C Zhao
- Department of Urology, Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou, China
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11
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Liu JY, Li H, Liu Y, Shi CH, Liang ZL, Wang LH, Zhang Y, Zhao Y, Fan YM, Wu B, Yu YZ. [Study on the effect and mechanism of hepatitis B virus X protein transactivates gene 4 in HepG2 cell apoptosis]. Zhonghua Gan Zang Bing Za Zhi 2019; 27:693-697. [PMID: 31594094 DOI: 10.3760/cma.j.issn.1007-3418.2019.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the effect and mechanism of XTP4 gene in apoptotic hepatoblastoma HepG2 cell line. Methods: HepG2 cells were transiently transfected with small interfering RNA of XTP4 genes, plasmid pcDNA3.1/myc-His(-) A-XTP4, and hepatitis B virus X protein transactivated x gene 4 (HBX protein trans-activate gene4, XTP4) and their respective negative controls. After 48h, the overexpression and interference expression condition of XTP4 in HepG2 cells were detected by Western blot. HepG2 cells apoptosis was detected by flow cytometry. The expression levels of apoptosis-related proteins P53, Bcl-2, Bax and Caspase-3 in HepG2 cells were detected by Western blot, and Bcl-2/Bax ratio was calculated. The chemiluminescence assay was used to detect activity of caspase-3 in HepG2 cells. The measured data were presented as (x ± s), and independent sample t-test was used for comparison between the two groups. Results: HepG2 cells had successfully achieved the overexpression and interference expression of XTP4 protein. Compared with the control group, the overexpression of XTP4 in HepG2 cells had significantly decreased the number of apoptotic cells (P < 0.05), and increased Bcl-2/Bax (P < 0.05) ratio, but decreased the expression of P53 protein (P < 0.05). The protein expression of Caspase-3 and activity of caspase-3 was decreased (P < 0.05). However, interference with XTP4 expression in HepG2 cells had significantly increased the number of apoptotic cells (P < 0.05) and decreased Bcl-2/Bax (P < 0.05) ratio, but increased the expression of P53 protein (P < 0.05). The protein expression of Caspase-3 and activity of caspase-3 was increased (P<0.05). Conclusion: In HepG2 apoptosis XTP4 has inhibitory effect, and its effect on inhibiting HepG2 apoptosis may be achieved by regulating the Bcl-2/Bax ratio, and the P53 protein may be involved.
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Affiliation(s)
- J Y Liu
- Zhoukou Central Hospital, Zhoukou 466000, China
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12
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Shi DY, Liu FJ, Mao YY, Cui RT, Lu JS, Yu YZ, Dong XJ, Yang ZX, Sun ZW, Pang XB. Development and evaluation of candidate subunit vaccine and novel antitoxin against botulinum neurotoxin serotype E. Hum Vaccin Immunother 2019; 16:100-108. [PMID: 31210561 DOI: 10.1080/21645515.2019.1633878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are among the most toxic proteins. Vaccination is an effective strategy to prevent botulism. To generate a vaccine suitable for human use, a recombinant non-His-tagged isoform of the Hc domain of botulinum neurotoxin serotype E (rEHc) was expressed in Escherichia coli and purified by sequential chromatography. The immunogenicity of rEHc was evaluated in mice and dose- and time-dependent immune responses were observed in both antibody titers and protective potency. Then, the pilot-scale expression and purification of rEHc were performed, and its immunological activity was characterized. Our results showed rEHc has good immunogenicity and can elicit strong protective potency against botulinum neurotoxin serotype E (BoNT/E) in mice, indicating that rEHc is an effective botulism vaccine candidate. Further, we developed a novel antitoxin against BoNT/E by purifying F(ab')2 from pepsin-digested serum IgG of rEHc-inoculated horses. The protective effect of the F(ab')2 antitoxin was determined in vitro and in vivo. The results showed that our F(ab')2 antitoxin can prevent botulism in BoNT/E-challenged mice and effectively alleviate the progression of paralysis caused by BoNT/E to achieve therapeutic effects. Therefore, our results provide valuable experimental data for the production of a novel antitoxin, which is a promising candidate for the treatment of BoNT/E-induced botulism.
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Affiliation(s)
- Dan-Yang Shi
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Fu-Jia Liu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.,Pharmaceutical College, Henan University, Kaifeng, China
| | - Yun-Yun Mao
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Rong-Tian Cui
- Department of Drug Registration, Jiangsu T-mab BioPharma Co., Ltd, Taizhou, China
| | - Jian-Sheng Lu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Yun-Zhou Yu
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Xiao-Jie Dong
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Zhi-Xin Yang
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Zhi-Wei Sun
- Department of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng, China
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13
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Shi DY, Chen BY, Mao YY, Zhou G, Lu JS, Yu YZ, Zhou XW, Sun ZW. Development and evaluation of candidate subunit vaccine against botulinum neurotoxin serotype B. Hum Vaccin Immunother 2018; 15:755-760. [PMID: 30433836 DOI: 10.1080/21645515.2018.1547613] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are potential biological weapons because of their high toxicity and mortality. Vaccination is an effective strategy to prevent botulism. The carboxyl-terminus of the heavy chain (Hc domain) is nontoxic and sufficient to generate protective immune responses against natural BoNTs in animals. To produce a vaccine suitable for human use, a recombinant non His-tagged isoform of the Hc domain of botulinum neurotoxin serotype B (BHc) was expressed in Escherichia coli and purified by sequential chromatography. The immunogenicity of recombinant E.coli-expressed BHc and the yeast-expressed mBHc antigens was explored and compared in Balb/c mice. BHc provided comparable protective potency but elicited significantly higher antibody titer and neutralization potency against BoNT/B after twice immunization, indicating that the recombinant BHc protein expressed in E.coli have better immunogenicity than the yeast-expressed mBHc. Moreover, a frequency and dose-dependent effect was observed in mice immunized with BHc subunit vaccine and the anti-BHc ELISA antibody titers correlated well with neutralizing antibody titers and protection potency. In summary, the Alhydrogel-formulated BHc subunit vaccine afforded effective protection against BoNT/B challenge. Therefore, the non-His-tagged and homogeneous BHc expressed in E.coli represents a good potential candidate subunit vaccine for human use.
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Affiliation(s)
- Dan-Yang Shi
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Bo-Yang Chen
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Yun-Yun Mao
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Guo Zhou
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Jian-Sheng Lu
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Yun-Zhou Yu
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Xiao-Wei Zhou
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
| | - Zhi-Wei Sun
- a Department of Protein Engineering , Beijing Institute of Biotechnology , Beijing , China
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14
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Yu XY, Qiu WY, Long F, Yang XP, Zhang C, Xu L, Chang HY, Du P, Hou XJ, Yu YZ, Zeng DD, Wang S, Sun ZW. A novel fully human anti-CD47 antibody as a potential therapy for human neoplasms with good safety. Biochimie 2018; 151:54-66. [PMID: 29864508 DOI: 10.1016/j.biochi.2018.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 05/30/2018] [Indexed: 01/07/2023]
Abstract
Strategies for targeting CD47 are becoming a hot spot of cancer immunotherapy. However the ubiquitous expression of CD47, especially on the RBC, makes the targeted therapy facing safety risk issues. So, how to balance the safety and efficacy during CD47 inhibition is currently a major question. We had reported an anti-CD47 antibody ZF1 with potent anti-tumor effect. In this study, we further developed and assessed a novel fully human anti-CD47 antibody, AMMS4-G4, derived from ZF1 using affinity maturation. AMMS4-G4 exhibited equivalent anticancer effects with Hu5F9-G4, a humanized anti-CD47 antibody in clinical trial, on the potential of inducing significant phagocytosis of tumor cells in vitro and prolonging the survival of leukemia xenografted mice. Additionally, AMMS4-G4 significantly inhibited the growth of grafted solid tumors by enhancing macrophage infiltration and modestly enhanced the anti-tumor activity of opsonizing antibody and antiangiogenic therapy. In cynomolgus monkeys, AMMS4-G4 was safely administered, was well tolerated at doses of 30 and 60 mg/kg, and did not produce serious adverse events, except for the reversible anemia, which was observed after 3 days and started to recover from 9 days later. Remarkably, it was proved by in vitro assay that Hu5F9-G4 induced RBC hemagglutination which wasn't observed in AMMS4-G4. On the whole, AMMS4-G4 was demonstrated to be a promising candidate with great potential and safe profile for cancer immunotherapy.
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Affiliation(s)
- Xiao-Yan Yu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Wei-Yi Qiu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Feng Long
- Department of Pharmacy, Maternal and Child Health Care Hospital of Zaozhuang, 25 Wenhua East Road, Zaozhuang, 277100, China.
| | - Xiao-Peng Yang
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Chang Zhang
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Lei Xu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Hong-Yan Chang
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Peng Du
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Xiao-Juan Hou
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Da-di Zeng
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Shuang Wang
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
| | - Zhi-Wei Sun
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China.
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15
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Chen BY, Zhou G, Li QL, Lu JS, Shi DY, Pang XB, Zhou XW, Yu YZ, Huang PT. Enhanced effects of DNA vaccine against botulinum neurotoxin serotype A by targeting antigen to dendritic cells. Immunol Lett 2017; 190:118-124. [PMID: 28802641 DOI: 10.1016/j.imlet.2017.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/02/2017] [Accepted: 08/05/2017] [Indexed: 11/25/2022]
Abstract
As dendritic cells (DCs) play a critical role in priming antigen-specific immune responses, the efficacy of DNA vaccines may be enhanced by targeting the encoded antigen proteins to DCs. In this study, we constructed a DC-targeted DNA vaccine encoding the Hc domain of botulinum neurotoxin serotype A (AHc) fused with scDEC, a single-chain Fv antibody (scFv) specific for the DC-restricted antigen-uptake receptor DEC205. Intramuscular injections of mice with the DC-targeted DNA vaccine (pVAX1-scDEC-AHc) stimulated more DCs to mature than the non-targeted DNA vaccine (pVAX1-SAHc) in the splenocytes. The DC-targeted DNA vaccine could induce more DCs maturation at the site of inoculation. The DC-targeted DNA vaccine induced stronger AHc-specific humoral immune responses, lymphocyte proliferative responses and protective potency against BoNT/A in mice than did pVAX1-SAHc. Moreover, the DC-targeting DNA vaccine provided effective protection after only two inoculations. In summary, these results showed that the DC-targeted fusion DNA vaccine could generate strong immunity, indicating that maturation of DCs induced by pVAX1-scDEC-AHc may be helpful for priming and boosting immune responses. Thus, we propose that the strategy of targeting antigen to DCs in vivo via DEC205 can enhance effectively the potency of DNA vaccines against BoNTs or other pathogens in an animal model.
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Affiliation(s)
- Bo-Yang Chen
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Guo Zhou
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Qing-Li Li
- Beijing Institute of Biotechnology, Beijing 100071, China; Pharmaceutical College, Henan University, Kaifeng 475001, China
| | - Jian-Sheng Lu
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Dan-Yang Shi
- Beijing Institute of Biotechnology, Beijing 100071, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng 475001, China.
| | - Xiao-Wei Zhou
- Beijing Institute of Biotechnology, Beijing 100071, China.
| | - Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing 100071, China.
| | - Pei-Tang Huang
- Beijing Institute of Biotechnology, Beijing 100071, China
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16
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Yu YZ, Xu Q. Prophylactic immunotherapy of Alzheimer's disease using recombinant amyloid-β B-cell epitope chimeric protein as subunit vaccine. Hum Vaccin Immunother 2016; 12:2801-2804. [PMID: 27379885 DOI: 10.1080/21645515.2016.1197456] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder that impairs memory and cognition. The neuropathological features of the disease include senile plaques (SPs), neurofibrillary tangles (NFTs) and neuronal loss in affected brain regions. The amyloid cascade hypothesis suggests that production and accumulation of excessive amyloid-β (Aβ) may be the main cause in the onset and progression of Alzheimer's disease. Active and passive immunotherapy targeting Aβ may be the most promising strategy to prevent or treat AD. This commentary focuses on the prophylactic immunotherapy of Alzheimer's disease using recombinant Aβ B-cell epitope chimeric protein as subunit vaccine targeting amyloid-β. We discuss the efficiency and perspective of this type of recombinant subunit protein vaccine and suggest a novel direction on the path to a successful AD immunotherapy. This novel chimeric protein immunogen as subunit vaccine of AD may be designed to mimic the assembly states of Aβ42 or oligomers using multivalent foldable Aβ1-15 (B cell epitopes of Aβ42) and foreign T helper (Th) epitopes (as the T cell epitopes of Aβ42) constructs.
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Affiliation(s)
- Yun-Zhou Yu
- a Beijing Institute of Biotechnology , Beijing , China
| | - Qing Xu
- b Institute of Life Science and Biotechnology, Beijing Jiaotong University , Beijing , China
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17
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Yu YZ, Liu S, Ma Y, Gong ZW, Wang S, Sun ZW. Pentavalent replicon vaccines against botulinum neurotoxins and tetanus toxin using DNA-based Semliki Forest virus replicon vectors. Hum Vaccin Immunother 2015; 10:1874-9. [PMID: 25424795 PMCID: PMC4186014 DOI: 10.4161/hv.28937] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The clostridial neurotoxin (CNT) family includes botulinum neurotoxin (BoNT), serotypes A, B, E, and F of which can cause human botulism, and tetanus neurotoxin (TeNT), which is the causative agent of tetanus. This suggests that the greatest need is for a multivalent or multiagent vaccine that provides protection against all 5 agents. In this study, we investigated the feasibility of generating several pentavalent replicon vaccines that protected mice against BoNTs and TeNT. First, we evaluated the potency of individual replicon DNA or particle vaccine against TeNT, which induced strong antibody and protective responses in BALB/c mice following 2 or 3 immunizations. Then, the individual replicon TeNT vaccines were combined with tetravalent BoNTs vaccines to prepare 4 types of pentavalent replicon vaccines. These replicon DNA or particle pentavalent vaccines could simultaneously and effectively induce antibody responses and protect effects against the 5 agents. Finally, a solid-phase assay showed that the sera of pentavalent replicon formulations-immunized mice inhibited the binding of THc to the ganglioside GT1b as the sera of individual replicon DNA or particle-immunized mice. These results indicated these pentavalent replicon vaccines could protect against the 4 BoNT serotypes and effectively neutralize and protect the TeNT. Therefore, our studies demonstrate the utility of combining replicon DNA or particle vaccines into multi-agent formulations as potent pentavalent vaccines for eliciting protective responses against BoNTs and TeNT.
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Affiliation(s)
- Yun-Zhou Yu
- a Beijing Institute of Biotechnology; Beijing, PR China
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18
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Zhao H, Wang QT, Geng SQ, Xu J, Yu YZ, Yu ZG. PROTEIN EXPRESSION OF METADHERIN AND SENSIBILITY OF BREAST CANCER MDA-MB-231 CELLS TO TREATMENT BEFORE AND AFTER TRANSFECTION. J BIOL REG HOMEOS AG 2015; 29:459-464. [PMID: 26122237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Breast cancer tends to have an increasing mortality, severely threatening the health of females. The invasion and metastasis of breast cancer are the leading causes of death. It has been reported that breast cancer is caused by the activation of a series of proto-oncogenes and inactivation of anti-oncogenes. In the present study, Real-time PCR and Western blot were used to detect the protein expression level of metadherin before and after transfecting MDA-MB-231 cells to identify the effect, while the sensitivity of MDA-MB-231 cells to 1 mg/L doxorubicin and 8mg/L taxol was measured by methylthiazolyldiphenyl-tetrazolium bromide (MTT). The results demonstrated that mRNA and protein expression level of metadherin both improved after transfection. The inhibition effect of 1 mg/L doxorubicin and 8 mg/L taxol on breast cancer cells decreased after transfection. Detected by flow cytometry, the apoptosis rate of breast cancer cells was 39.68±0.42%, 20.64±0.55%, respectively, under the effect of 1 mg/L doxorubicin; while under the effect of 8 mg/L taxol, the rate was 24.89±0.41% and 13.8±0.63%, respectively. Thus the inhibition effects of 1 mg/L doxorubicin and 8mg/L taxol to breast cancer cells and their effects on apoptosis were different, and the differences were statistically significant (P<0.05). Based on the statistics on the expression level of metadherin after transfecting breast cancer cells MDA-MB-231 and the exploration of the sensitivity of the cells to treatment, the effect of metadherin on breast cancer MDA-MB-232 cells was proved.
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Affiliation(s)
- H Zhao
- Department of Breast Disease, the Second Hospital of Shandong University, Jinan, China
| | - Q T Wang
- Department of Breast Disease, the Second Affiliated Hospital of Qingdao University Medical College, Qingdao, China
| | - S Q Geng
- Department of Pathology, the Second Affiliated Hospital of Qingdao University Medical College, Qingdao, Shandong, China
| | - J Xu
- Department of Pathology, the Second Affiliated Hospital of Qingdao University Medical College, Qingdao, Shandong, China
| | - Y Z Yu
- Department of Breast Disease, the Second Affiliated Hospital of Qingdao University Medical College, Qingdao, China
| | - Z G Yu
- Department of Breast Disease, the Second Hospital of Shandong University, Jinan, China
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Wang HC, An HJ, Yu YZ, Xu Q. Potentiation of anthrax vaccines using protective antigen-expressing viral replicon vectors. Immunol Lett 2015; 163:206-13. [DOI: 10.1016/j.imlet.2014.07.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 07/18/2014] [Accepted: 07/27/2014] [Indexed: 11/17/2022]
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20
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Yu YZ, Wang WB, Chen A, Chang Q, Liu S, Zhao M, Wang S, Qiu WY, Pang XB, Xu Q, Sun ZW. Strikingly reduced amyloid burden and improved behavioral performance in Alzheimer's disease mice immunized with recombinant chimeric vaccines by hexavalent foldable Aβ₁₋₁₅ fused to toxin-derived carrier proteins. J Alzheimers Dis 2015; 41:243-60. [PMID: 24625800 DOI: 10.3233/jad-132177] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Targeting on the amyloid-β (Aβ) is a promising immunotherapeutic strategy for Alzheimer's disease (AD). However, Aβ(1-15) sequence alone induces low antibody response and poor protection against AD. We describe here the immunological characterization and protective efficacy of several recombinant chimeric vaccines with hexavalent foldable Aβ(1-15) (6Aβ15) fused to PADRE or toxin-derived carrier proteins. Immunization with these chimeric antigens generated robust Th2 immune responses with high anti-Aβ42 antibody titers in different mice, which recognized neurotoxic Aβ42 oligomers, but did not stimulate Aβ42-specific T cell responses. These 6Aβ15 chimeric vaccines markedly reduced Aβ pathology and prevented development of behavioral deficits in immunized older AD mice. Importantly, toxin-derived carrier proteins as molecular adjuvants of chimeric vaccines could substantially boost immune responses and overcome Aβ- and old age-associated hypo-responsiveness, and elicit long-term Aβ-specific antibody response, which in turn inhibited Aβ-mediated pathology and improved acquisition and retention of spatial memory in immunized AD mice. These data indicate that toxin fragments as molecular adjuvants are promising new tools for the rational design and development of prototype chimeric vaccines for AD and this type of chimeric vaccine design has the added advantage of overcoming hypo-responsiveness in elderly AD patients with pre-existing memory Th cells from tetanus toxin.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, China
| | - Wen-Bin Wang
- Beijing Institute of Biotechnology, Beijing, China
| | - Ao Chen
- Beijing Institute of Biotechnology, Beijing, China Pharmaceutical College, Henan University, Kaifeng, China
| | - Qing Chang
- Beijing Institute of Biotechnology, Beijing, China
| | - Si Liu
- Beijing Institute of Biotechnology, Beijing, China
| | - Meng Zhao
- Beijing Institute of Biotechnology, Beijing, China Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, China
| | - Shuang Wang
- Beijing Institute of Biotechnology, Beijing, China
| | - Wei-Yi Qiu
- Beijing Institute of Biotechnology, Beijing, China
| | - Xiao-Bin Pang
- Pharmaceutical College, Henan University, Kaifeng, China
| | - Qing Xu
- Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing, China
| | - Zhi-Wei Sun
- Beijing Institute of Biotechnology, Beijing, China
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21
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Yu Y, Shi D, Liu S, Gong ZW, Wang S, Sun Z. Production and evaluation of a recombinant subunit vaccine against botulinum neurotoxin serotype B using a 293E expression system. Hum Vaccin Immunother 2014; 11:468-73. [PMID: 25483668 DOI: 10.4161/hv.29714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Although Escherichia coli and yeast were commonly used to express recombinant Hc of botulinum neurotoxins, as an alternative, in current study, a 293E expression system was used to express the Hc of botulinum neurotoxin serotype B (BHc) as soluble recombinant protein for experimental vaccine evaluation. Our results demonstrated that the 293E expression system could produce high level of recombinant secreted BHc protein, which was immunorecognized specifically by anti-botulinum neurotoxin serotype B (BoNT/B) sera and showed ganglioside binding activities. The serological response and efficacy of recombinant BHc formulated with aluminum hydroxide adjuvant were evaluated in mice. Immunization with Alhydrogel-formulated BHc subunit vaccine afforded the effective protection against BoNT/B challenge. A frequency- and dose-dependent effect to immunization with BHc subunit vaccine was observed and the ELISA antibody titers correlated well with neutralizing antibody titers and protection. And a solid-phase assay showed that the neutralizing antibodies from the BHc-immunized mice inhibited the binding of BHc to the ganglioside GT1b. Our results also show that the plasmid pABE293SBHc derived of the 293E expression system as DNA vaccine is capable of inducing stronger humoral response and protective efficacy against BoNT/B than the pVAX1SBHc. In summary, immunization with the 293E-expressed BHc protein generates effective immune protection against BoNT/B as E. coli or yeast-expressed BHc, so the efficient expression of botulinum Hc protein for experimental vaccine can be prepared using the 293E expression system.
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Affiliation(s)
- YunZhou Yu
- a Beijing Institute of Biotechnology ; Beijing , PR China
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22
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Yu YZ, Ma Y, Chen YX, Gong ZW, Wang S, Yu WY, Yu YZ. Binding activity and immunogenic characterization of recombinant C-terminal quarter and half of the heavy chain of botulinum neurotoxin serotype A. Human Vaccines 2014; 7:1090-5. [DOI: 10.4161/hv.7.10.16763] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Yu YZ, Ma Y, Xu WH, Wang S, Sun ZW. Combinations of various CpG motifs cloned into plasmid backbone modulate and enhance protective immunity of viral replicon DNA anthrax vaccines. Med Microbiol Immunol 2014; 204:481-91. [PMID: 25265876 DOI: 10.1007/s00430-014-0359-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 09/16/2014] [Indexed: 10/24/2022]
Abstract
DNA vaccines are generally weak stimulators of the immune system. Fortunately, their efficacy can be improved using a viral replicon vector or by the addition of immunostimulatory CpG motifs, although the design of these engineered DNA vectors requires optimization. Our results clearly suggest that multiple copies of three types of CpG motifs or combinations of various types of CpG motifs cloned into a viral replicon vector backbone with strong immunostimulatory activities on human PBMC are efficient adjuvants for these DNA vaccines to modulate and enhance protective immunity against anthrax, although modifications with these different CpG forms in vivo elicited inconsistent immune response profiles. Modification with more copies of CpG motifs elicited more potent adjuvant effects leading to the generation of enhanced immunity, which indicated a CpG motif dose-dependent enhancement of antigen-specific immune responses. Notably, the enhanced and/or synchronous adjuvant effects were observed in modification with combinations of two different types of CpG motifs, which provides not only a contribution to the knowledge base on the adjuvant activities of CpG motifs combinations but also implications for the rational design of optimal DNA vaccines with combinations of CpG motifs as "built-in" adjuvants. We describe an efficient strategy to design and optimize DNA vaccines by the addition of combined immunostimulatory CpG motifs in a viral replicon DNA plasmid to produce strong immune responses, which indicates that the CpG-modified viral replicon DNA plasmid may be desirable for use as vector of DNA vaccines.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing, 100071, China,
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Yu YZ, Wang S, Bai JY, Zhao M, Chen A, Wang WB, Chang Q, Liu S, Qiu WY, Pang XB, Xu Q, Sun ZW. Effective DNA epitope chimeric vaccines for Alzheimer's disease using a toxin-derived carrier protein as a molecular adjuvant. Clin Immunol 2013; 149:11-24. [DOI: 10.1016/j.clim.2013.05.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 04/30/2013] [Accepted: 05/25/2013] [Indexed: 10/26/2022]
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Ma Y, Yu YZ, Zhu YF, Xu Q, Sun ZW. In vitro and in vivo activities of recombinant anthrax protective antigen co-expressed with thioredoxin in Escherichia coli. Hum Vaccin Immunother 2013; 9:2371-7. [PMID: 23880942 DOI: 10.4161/hv.25748] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Because of the central role it plays in the formation of lethal toxin and edema toxin, protective antigen (PA) is the principal target for the development of vaccines against anthrax. In the present study, we explored and compared the in vitro and in vivo activities of recombinant anthrax protective antigen (rPA) and receptor binding domain of protective antigen (PA4). As a result, the fully soluble rPA and PA4 proteins were successfully expressed in Escherichia coli by co-expression with thioredoxin (Trx), and the rPA was active in forming cytotoxic lethal toxins, indicating that the rPA protein retains a functionally biological activity. Furthermore, immunization with rPA protein induced stronger PA-specific immune responses in mice than PA4 protein. The protection elicited by immunization with PA4 suggests the presence of common neutralizing epitopes between rPA and PA4, but the immunization with rPA protein induced stronger neutralizing antibodies and protective levels against challenge with the B. anthracis strain A16R than the PA4 protein. The sera neutralizing antibodies titers correlated well with anti-PA group ELISA antibodies titers and the in vivo protective potency. Based on the results of cell cytotoxicity assays and the observed immune responses and protective potency, we concluded that the soluble rPA protein retains the in vitro and in vivo functionally biological activity and can be developed into a highly effective human subunit vaccine candidate against anthrax.
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Affiliation(s)
- Yao Ma
- College of Life Science and Bioengineering; Beijing Jiaotong University; Beijing, P.R. China; Beijing Institute of Biotechnology; Beijing, P.R. China
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Yu YZ, Guo JP, An HJ, Zhang SM, Wang S, Yu WY, Sun ZW. Potent tetravalent replicon vaccines against botulinum neurotoxins using DNA-based Semliki Forest virus replicon vectors. Vaccine 2013; 31:2427-32. [PMID: 23583890 DOI: 10.1016/j.vaccine.2013.03.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 02/07/2013] [Accepted: 03/28/2013] [Indexed: 10/26/2022]
Abstract
Human botulism is commonly associated with botulinum neurotoxin (BoNT) serotypes A, B, E and F. This suggests that the greatest need is for a tetravalent vaccine that provides protection against all four of these serotypes. In current study, we investigated the feasibility of generating several tetravalent vaccines that protected mice against the four serotypes. Firstly, monovalent replicon vaccine against BoNT induced better antibody response and protection than that of corresponding conventional DNA vaccine. Secondly, dual-expression DNA replicon pSCARSE/FHc or replicon particle VRP-E/FHc vaccine was well resistant to the challenge of BoNT/E and BoNT/F mixture as a combination vaccine composed of two monovalent replicon vaccines. Finally, the dual-expression DNA replicon or replicon particle tetravalent vaccine could simultaneously and effectively neutralize and protect the four BoNT serotypes. Protection correlated directly with serum ELISA titers and neutralization antibody levels to BoNTs. Therefore, replicon-based DNA or particle might be effective vector to develop BoNT vaccines, which might be more desirable for use in clinical application than the conventional DNA vaccines. Our studies demonstrate the utility of combining dual-expression DNA replicon or replicon particle vaccines into multi-agent formulations as potent tetravalent vaccines for eliciting protective responses to four serotypes of BoNTs.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, China.
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Ma Y, An HJ, Wei XQ, Xu Q, Yu YZ, Sun ZW. Enhanced potency of replicon vaccine using one vector to simultaneously co-express antigen and interleukin-4 molecular adjuvant. Hum Vaccin Immunother 2013; 9:242-9. [PMID: 23291932 DOI: 10.4161/hv.22888] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We evaluated the utility of interleukin-4 (IL-4) as molecular adjuvant of replicon vaccines for botulinum neurotoxin serotype A (BoNT/A) in mouse model. In both Balb/c and C57/BL6 mice that received the plasmid DNA replicon vaccines derived from Semliki Forest virus (SFV) encoding the Hc gene of BoNT/A (AHc), the immunogenicity was significantly modulated and enhanced by co-delivery or co-express of the IL-4 molecular adjuvant. The enhanced potencies were also produced by co-delivery or co-expression of the IL-4 molecular adjuvant in mice immunized with the recombinant SFV replicon particles (VRP) vaccines. In particular, when AHc and IL-4 were co-expressed within the same replicon vaccine vector using dual-expression or bicistronic IRES, the anti-AHc antibody titers, serum neutralization titers and survival rates of immunized mice after challenged with BoNT/A were significantly increased. These results indicate IL-4 is an effective Th2-type adjuvant for the replicon vaccines in both strain mice, and the co-expression replicon vaccines described here may be an excellent candidate for further vaccine development in other animals or humans. Thus, we described a strategy to design and develop efficient vaccines against BoNT/A or other pathogens using one replicon vector to simultaneously co-express antigen and molecular adjuvant.
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Affiliation(s)
- Yao Ma
- College of Life Science and Bioengineering; Beijing Jiaotong University; Beijing, PR China
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Yu YZ, Li N, Ma Y, Wang S, Yu WY, Sun ZW. Three types of human CpG motifs differentially modulate and augment immunogenicity of nonviral and viral replicon DNA vaccines as built-in adjuvants. Eur J Immunol 2012; 43:228-39. [PMID: 23037552 DOI: 10.1002/eji.201242690] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Revised: 09/14/2012] [Accepted: 10/01/2012] [Indexed: 01/20/2023]
Abstract
NakedDNA vaccines given by intramuscular injection are efficient in mouse models, but they require improvement for human use. As the immunogenicity of DNA vaccines depends, to a large extent, on the presence of CpG motifs as built-in adjuvants, we addressed this issue by inserting three types of human CpG motifs (A-type, B-type, and C-type) into the backbone of nonviral DNA and viral DNA replicon vectors with distinct immunostimulatory activities on human PBMCs. The adjuvant effects of CpG modifications in DNA vaccines expressing three types of antigens (β-Gal, AHc, or PA4) were then characterized in mice and found to significantly enhance antigen-specific humoral and cell-mediated immune responses. The three types of CpG motifs also differentially affected and modulated immune responses and protective potency against botulinum neurotoxin serotype A and Bacillus anthracis A16R challenge. Taken together, these results demonstrate that insertion of human CpG motifs can differentially modulate the immunogenicity of nonviral DNA vaccines as well as viral DNA replicon vaccines. Our study provides not only a better understanding of the in vivo activities of CpG motif adjuvants but implications for the rational design of such motifs as built-in adjuvants for DNA vectors targeting specific antigens.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, China.
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Yu YZ, Gong ZW, Ma Y, Zhang SM, Zhu HQ, Wang WB, Du Y, Wang S, Yu WY, Sun ZW. Co-expression of tetanus toxin fragment C in Escherichia coli with thioredoxin and its evaluation as an effective subunit vaccine candidate. Vaccine 2011; 29:5978-85. [PMID: 21718736 DOI: 10.1016/j.vaccine.2011.06.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 05/02/2011] [Accepted: 06/13/2011] [Indexed: 12/12/2022]
Abstract
The receptor-binding domain of tetanus toxin (THc), which mediates the binding of the toxin to the nerve cells, is a candidate subunit vaccine against tetanus. In this study one synthetic gene encoding the THc was constructed and highly expressed in Escherichia coli by co-expression with thioredoxin (Trx). The purified THc-vaccinated mice were completely protected against an active toxin challenge in mouse models of disease and the potency of two doses of THc was comparable to that of three doses of toxoid vaccine. And a solid-phase assay showed that the anti-THc sera inhibited the binding of THc or toxoid to the ganglioside GT1b as the anti-tetanus toxoid sera. Furthermore, mice were vaccinated once or twice at four different dosages of THc and a dose-response was observed in both the antibody titer and protective efficacy with increasing dosage of THc and number of vaccinations. The data presented in the report showed that the recombinant THc expressed in E. coli is efficacious in protecting mice against challenge with tetanus toxin suggesting that the THc protein may be developed into a human subunit vaccine candidate designed for the prevention of tetanus.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing 100071, PR China.
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Li N, Yu YZ, Yu WY, Sun ZW. Enhancement of the immunogenicity of DNA replicon vaccine of Clostridium botulinum neurotoxin serotype A by GM-CSF gene adjuvant. Immunopharmacol Immunotoxicol 2011; 33:211-9. [PMID: 21284488 DOI: 10.3109/08923971003782327] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Granulocyte-macrophage clony-stimulating factor (GM-CSF) is an attractive adjuvant for a DNA vaccine on account of its ability to recruit antigen-presenting cells to the site of antigen synthesis as well as stimulate the maturation of dendritic cells.This study evaluated the utility of GM-CSF as a plasmid DNA replicon vaccine adjuvants for botulinum neurotoxin serotype A (BoNT/A) in mouse model. In balb/c mice that received the plasmid DNA replicon vaccines derived from Semliki Forest virus (SFV) carrying the Hc gene of BoNT/A (AHc), both antibody and lymphoproliferative response specific to AHc were induced, the immunogenicity was enhanced by co-delivery or coexpress of the GM-CSF gene. In particular, when AHc and GM-CSF were coexpressed within the SFV based DNA vaccine, the anti-AHc antibody titers and survival rates of immunized mice after challenged with BoNT/A were significantly increased, and further enhanced by coimmunization with aluminum phosphate adjuvant.
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Affiliation(s)
- Na Li
- Beijing Institute of Biotechnology, Beijing, China
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Yu YZ, Wang WB, Li N, Wang S, Yu WY, Sun ZW. Enhanced potency of individual and bivalent DNA replicon vaccines or conventional DNA vaccines by formulation with aluminum phosphate. Biologicals 2011; 38:658-63. [PMID: 20805035 DOI: 10.1016/j.biologicals.2010.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2010] [Revised: 08/04/2010] [Accepted: 08/04/2010] [Indexed: 10/19/2022] Open
Abstract
DNA vaccines against botulinum neurotoxin (BoNTs) induce protective humoral immune responses in mouse model, but when compared with conventional vaccines such as toxoid and protein vaccines, DNA vaccines often induce lower antibody level and protective efficacy and are still necessary to increase their potency. In this study we evaluated the potency of aluminum phosphate as an adjuvant of DNA vaccines to enhance antibody responses and protective efficacy against botulinum neurotoxin serotypes A and B in Balb/c mice. The administration of these individual and bivalent plasmid DNA replicon vaccines against botulinum neurotoxin serotypes A and B in the presence of aluminum phosphate improved both antibody responses and protective efficacy. Furthermore, formulation of conventional plasmid DNA vaccines encoding the same Hc domains of botulinum neurotoxin serotypes A and B with aluminum phosphate adjuvant increased both antibody responses and protective efficacy. These results indicate aluminum phosphate is an effective adjuvant for these two types of DNA vaccines (i.e., plasmid DNA replicon vaccines and conventional plasmid DNA vaccines), and the vaccine formulation described here may be an excellent candidate for further vaccine development against botulinum neurotoxins.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Protein Engineering of Lab, 20 Dong Dajie Street, Fengtai District, Beijing 100071, China.
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Yu YZ, Zhang SM, Ma Y, Zhu HQ, Wang WB, Du Y, Zhou XW, Wang RL, Wang S, Yu WY, Huang PT, Sun ZW. Development and evaluation of candidate vaccine and antitoxin against botulinum neurotoxin serotype F. Clin Immunol 2010; 137:271-80. [PMID: 20696619 DOI: 10.1016/j.clim.2010.07.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 07/19/2010] [Accepted: 07/19/2010] [Indexed: 11/29/2022]
Abstract
To produce a vaccine suitable for human use, a recombinant non His-tagged isoform of the Hc domain of botulinum neurotoxin serotype F (rFHc) was expressed in Escherichia coli and purified by sequential chromatography. The rFHc was evaluated as a subunit vaccine candidate in mouse model of botulism. A dose-response was observed in both antibody titer and protective efficacy with increasing dosage of rFHc and number of vaccinations. These findings suggest that the rFHc is an effective botulism vaccine candidate. Further, we developed a new antitoxin against botulinum neurotoxin serotype F (BoNT/F) by purifying F(ab')(2) fragments from pepsin digested serum IgGs of horses inoculated with rFHc. The protective effect of the F(ab')(2) antitoxin against BoNT/F was determined both in vitro and in vivo. The results showed that the F(ab')(2) antitoxin could prevent botulism in mice challenged with BoNT/F and effectively delayed progression of paralysis from botulism in the therapeutic setting. Thus, our results provide valuable experimental data for this new antitoxin as a potential candidate for treatment of botulism caused by BoNT/F.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, China.
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Yu YZ, Zhang SM, Wang WB, Du Y, Zhu HQ, Wang RL, Zhou XW, Lin JB, Wang S, Yu WY, Huang PT, Sun ZW. Development and preclinical evaluation of a new F(ab')₂ antitoxin against botulinum neurotoxin serotype A. Biochimie 2010; 92:1315-20. [PMID: 20600570 DOI: 10.1016/j.biochi.2010.06.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Accepted: 06/10/2010] [Indexed: 11/30/2022]
Abstract
Concern about the malicious applications of botulinum neurotoxin has highlighted the need for a new generation of safe and highly potent antitoxins. In this study, we developed and evaluated the preclinical pharmacology and safety of a new F(ab')₂ antitoxin against botulinum neurotoxin serotype A (BoNT/A). As an alternative to formalin-inactivated toxoid, the recombinant Hc domain of botulinum neurotoxin serotype A (rAHc) was used to immunize horses, and the IgGs from the hyperimmune sera were digested to obtain F(ab')₂ antitoxin. The protective effect of the new F(ab')₂ antitoxin against BoNT/A was determined both in vitro and in vivo. The results showed that the F(ab')₂ antitoxin could prevent botulism in mice challenged with BoNT/A and effectively delayed progression of paralysis from botulism in the therapeutic setting. The preclinical safety of the new F(ab')₂ antitoxin was also evaluated, and it showed neither harmful effects on vital functions nor adverse effects such as acute toxicity, or immunological reactions in mice and dogs. Thus, our results provide valuable experimental data for this new antitoxin as a potential candidate for treatment of botulism caused by BoNT/A, and our findings support the safety of the new F(ab')₂ antitoxin for clinical use. Our study further demonstrates the proof of concept for development of a similar strategy for obtaining potent antitoxin against other BoNT serotypes.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, Beijing, PR China
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Yu R, Wang S, Yu YZ, Du WS, Yang F, Yu WY, Sun ZW. Neutralizing antibodies of botulinum neurotoxin serotype A screened from a fully synthetic human antibody phage display library. ACTA ACUST UNITED AC 2009; 14:991-8. [PMID: 19726786 DOI: 10.1177/1087057109343206] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The botulinum neurotoxins (BoNTs) produced by Clostridium botulinum are the most poisonous protein substances known. The neutralizing antibodies against botulinum neurotoxin can effectively prevent and cure the toxicosis. Using purified Hc fragments of botulinum neurotoxin serotype A (BoNT/A-Hc) as antigen, 2 specific neutralizing antibodies mapping different epitopes were selected from a fully synthetic human antibody library. The 2 antibodies can effectively inhibit the binding between BoNT/A-Hc and differentiated PC-12 cells in vitro, and the neutralization was evaluated in vivo. Although no single mAb completely protected mice from toxin, they both could prolong time to death when challenged with 20 LD(50)s (50% lethal doses) of BoNT/A. When used together, the mAbs completely neutralized 1000 LD(50)s/mg Ab, suggesting their high neutralizing potency in vivo. The results would lead to further production of neutralizing antibody drugs against BoNT/A. It also proved that it was a quick method to obtain human therapeutic antibodies by selecting from the fully synthetic human antibody phage display library.
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Affiliation(s)
- Rui Yu
- Beijing Institute of Biotechnology, Beijing, China
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Yu YZ, Sun ZW, Li N, Wang S, Wang RL, Yu WY. Protection with a recombinant Hc ofClostridium Botulinumneurotoxin serotype A fromEscherichia colias an effective subunit vaccine. Immunopharmacol Immunotoxicol 2009; 31:261-6. [DOI: 10.1080/08923970802438433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Yu YZ, Li N, Zhu HQ, Wang RL, Du Y, Wang S, Yu WY, Sun ZW. The recombinant Hc subunit of Clostridium botulinum neurotoxin serotype A is an effective botulism vaccine candidate. Vaccine 2009; 27:2816-22. [DOI: 10.1016/j.vaccine.2009.02.091] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 02/09/2009] [Accepted: 02/25/2009] [Indexed: 10/21/2022]
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Yu YZ, Li N, Wang S, Yu WY, Sun ZW. Improved immunogenicity and protective efficacy of a replicon DNA vaccine encoding the Hc domain of botulinum neurotoxin serotype A by electric pulses and protein boosting. Immunopharmacol Immunotoxicol 2009; 31:397-404. [DOI: 10.1080/08923970802713470] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Yu YZ, Zhang SM, Sun ZW, Wang S, Yu WY. Enhanced immune responses using plasmid DNA replicon vaccine encoding the Hc domain of Clostridium botulinum neurotoxin serotype A. Vaccine 2007; 25:8843-50. [PMID: 18022294 DOI: 10.1016/j.vaccine.2007.10.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 09/14/2007] [Accepted: 10/07/2007] [Indexed: 11/19/2022]
Abstract
In current study, the immunogenicity of a plasmid DNA replicon vaccine (pSCARSHc) encoding the Hc domain of Clostridium botulinum neurotoxin serotype A (AHc) was investigated and compared with a conventional plasmid DNA vaccine (pcDNASHc) encoding the same antigen. In vitro, pSCARSHc incorporating Semliki Forest virus (SFV) replicon could express AHc protein and induce apoptosis of transfected cells. Comparison with the conventional plasmid DNA vaccine (pcDNASHc) yielded several interesting results. First, our self-designed pSCARSHc could induce relatively higher AHc-specific antibodies and lymphocyte proliferative responses in immunized Balb/c mice, especially at low doses. Second, while both pSCARSHc and pcDNASHc induced Th2-type immune responses, the ratio of IgG1 to IgG2a was lower in pSCARSHc groups and the Th2- and Th1-type humoral immune responses induced by pSCARSHc were also stronger than that of the pcDNASHc vaccine. Third, it was shown that the sera from pSCARSHc-vaccinated mice conferred more efficient protection than those from pcDNASHc-vaccinated mice by BoNT/A neutralization assay. Finally, mice immunized with pSCARSHc could also elicit more efficient protection against BoNT/A than pcDNASHc. These results indicate that our plasmid DNA replicon vaccine can provide strong immunogenicity and should be a potential alternative strategy to conventional DNA vaccines in developing an efficacious vaccine against C. botulinum neurotoxin serotype A.
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Affiliation(s)
- Yun-Zhou Yu
- Beijing Institute of Biotechnology, 20 Dong Dajie Street, Fengtai District, Beijing 100071, China
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Yu YZ, Sun ZW, Yu WY. [Construction of DNA and RNA based on bifunctional replicon vector derived from Semliki Forest virus]. Sheng Wu Gong Cheng Xue Bao 2005; 21:713-8. [PMID: 16285510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
DNA-based replicon expression vector pSMCTA and helper vector pSHCTA were constructed by replacing the SP6 promoter used in the original system pSFV1 and pSFV-helper2 derived from Semliki Forest virus (SFV) with the RNA polymerase II -dependent cytomegalovirus immediate early (CMV IE) enhancer/promoter and T7 promoter, and inserting BGH transcription termination and polyadenylation signal downstream 3'-untranslated region (UTR). The RNA polymerase II -dependent cytomegalovirus immediate early (CMV IE) enhancer/promoter and T7 promoter in pSMCTA and pSHCTA could drive transcription to produce replicon RNA in vivo and ex vivo. High level expression of foreign genes (GFP and LacZ) could be demonstrated by transfecting BHK21 cells with the new replicon expression vectors based on both DNA and RNA, and recombinant virus particles (RVP) be prepared by cotranfecting the expression vectors with the helper vectors. Foreign genes were also highly expressed in cells (BHK21) which were infected with RVP activated by alpha-chymotrypsin. The bifunctional replicon vectors can be used in highly efficient expression of foreign genes and preparation of RVP ex vivo, also in development of replicon vaccines and gene therapy vectors in vivo.
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Affiliation(s)
- Yun-Zhou Yu
- Institute of Biotechnology, Academy of Military Medical Sciences, Beijing 100071, China
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Yu YZ, Shi RF, Garito AF, Grossman CH. Origin of negative chi((3)) in squaraines: experimental observation of two-photon states. Opt Lett 1994; 19:786-788. [PMID: 19844445 DOI: 10.1364/ol.19.000786] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Femtosecond pump-probe experiments performed on squaraines demonstrate strong couplings between the first excited state and high-lying two-photon states. The experimental data agree well with our earlier quantum many-electron calculations based on multiple-excited configuration interactions. We show that high-lying twophoton states in squaraines are critically important to understanding the observed third-order optical properties and that two-level models are inadequate even for molecules with negative third-order optical susceptibilities.
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Yuan ZS, Yu YZ, Na ZY. [Chronic process with Non-A and Non-B hepatitis disseminated from the intestine (appended 500 cases followed up for two years)]. Kansenshogaku Zasshi 1991; 65:451-6. [PMID: 1906514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
At present Non-A and Non-B hepatitis disseminated from the intestine in the world is believed to have a better prognosis and has no chronicity. From 1980-1986, this hepatitis has occurred in the south of Xinjiang. It was sporadic (1980-1985) and there was an outbreak (1986). Our study indicated that the results from 500 cases followed up for two years were different from the literature reported. 1. Patients with hepatomegaly were 11.2% at 7th months, 12.8% at 19th months and 45.3% at 28th months. At the same time there were 3 cases of splenomegaly and spider in each of the 19th month and 28th month. 2. Liver function test showed that gamma-GTP, BSP and gamma-globulins rose in different degrees among the 3-7 month cases. Reexamined at 19th months, 3.6% cases of both ZTT and SGPT were high. General proteins of 8% patients dropped. In 42% of the patients the globulins rose and the album in dropped. 3. Biopsy of the liver after 28th months demonstrated that it was in agreement with the pathologic changes found in chronic lobule hepatitis of CPH under the light microscope and electron microscope.
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Affiliation(s)
- Z S Yuan
- Department of Infectious Disease People's Hospital, Xinjiang Uigur Autonomous Region
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She JW, Li MY, Wang KQ, Yu YZ. Prosthetic heart valves: waveform comparisons and average value disposition for pulsatile flow in vitro. J Biomed Eng 1990; 12:375-8. [PMID: 2214723 DOI: 10.1016/0141-5425(90)90019-j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
With the development of the in vitro testing of heart valves, the standardization of the test methods becomes increasingly important and they should also be improved continuously. This paper discusses the problems of waveform comparison and average value dispositions. In the pulsatile model driven by pneumatics, the pressures before and after the valve, and the flow through it, are measured as three one-dimensional variates. The mean values are calculated according to the FDA and the ISO. A comparison and analysis of experimental waveforms indicate that, for basically the same ranges of pressures and flow rate, the flow curves of different types of valve are clearly different. The mean values and the waveforms in the time domain should be taken into consideration synthetically so that the pusatile characteristics of the valve can be more completely reflected. Using numerical filtering methods to treat the waveforms allows for better comparisons between the measured results taken from the different devices. By means of the constellation graphical method for treating mean values as multivariates, it is feasible to classify the valves and to judge their qualities under conditions of pulsatile flow.
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Affiliation(s)
- J W She
- Department of Anatomy, Shanghai Medical University, China
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Cheng XM, Zheng SJ, Yu YZ. [Study on the blood supply of pedicled second and third metatarsal bone transplantations]. Zhonghua Wai Ke Za Zhi 1985; 23:665-7, 702. [PMID: 3830648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Yu YZ. [Investigation on the hygienic standard of environmental meteorology for underground work in coal mines]. Zhonghua Yu Fang Yi Xue Za Zhi 1984; 18:1-4. [PMID: 6468116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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45
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Yu YZ. [The energy expenditure and labor intensity of pitmen in underground coal cutting and drilling (author's transl)]. Zhonghua Yu Fang Yi Xue Za Zhi 1982; 16:31-4. [PMID: 7094738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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46
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Jiang WD, Yu YZ, Liu WW, Chen YH, Wang YP, Huang TC. [Effects of sodium tanshinone II-A sulfonate and propranolol on coronary collaterals in acutely infarcted dogs (author's transl)]. Zhongguo Yao Li Xue Bao 1981; 2:29-33. [PMID: 6461196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Yu YZ. [Study of the thermal insulation criteria of winter clothes (author's transl)]. Zhonghua Yu Fang Yi Xue Za Zhi 1980; 14:4-9. [PMID: 7227082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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48
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Yu YZ, Liu ZY, Li TL, Jin SX, Lu YF, Deng XX, Cai YN, Liao WI, Yan YZ, Yun JT, Li G, Lu Y, Wang FJ, Liang Y, Li JX, Lu WM. [The manufacture and efficiency test of the supplimental oxygen equipment for individuals working at high altitude (author's transl)]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1979; 1:259-64. [PMID: 233305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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49
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Yu YZ, Li TL, Liu ZY, Wang Q, Deng XX, Wu MX, Li G, Li LS, Liang Y, Cheng KR, Guo ML, Hu WS. [A study on the problem of labour hygiene and labour protection at high altitude (author's transl)]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1979; 1:248-55. [PMID: 162231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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50
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Yu YZ, Liu ZY, Jin SX, Chang XS, Cai YN, Yun JT, Mu ZY, Zhang CX, Liao DH, Li JX. [The effect of intermittent breathing of oxygen produced by supplemental oxygen equipment (SOE) upon the treatment of chronic altitude hypoxic symptoms (author's transl)]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1979; 1:265-7. [PMID: 552922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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