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Xue L.,Capital Medical University | Yao K.,Capital Medical University | Xie G.,Lanzhou Institute of Biological Products | Zheng Y.,Shenzhen Childrens Hospital | And 13 more authors.
Clinical Infectious Diseases | Year: 2010

A total of 171 Streptococcus pneumoniae isolates causing invasive disease were isolated from Chinese children. The serotype distribution and antimicrobial resistance were tested. The results suggested that the 7-valent pneumococcal conjugate vaccine has a preventive effect among children and that there should be long-term surveillance for serotype 19A. © 2010 by the Infectious Diseases Society of America. All rights reserved.

Liang X.-F.,U.S. Center for Disease Control and Prevention | Wang H.-Q.,U.S. Center for Disease Control and Prevention | Wang J.-Z.,National Institute for the Control of Pharmaceuticals and Biological Products | Fang H.-H.,National Institute for the Control of Pharmaceuticals and Biological Products | And 19 more authors.
The Lancet | Year: 2010

Background: The current influenza pandemic calls for a safe and effective vaccine. We assessed the safety and immunogenicity of eight formulations of 2009 pandemic influenza A H1N1 vaccine produced by ten Chinese manufacturers. Methods: In this multicentre, double-blind, randomised trial, 12 691 people aged 3 years or older were recruited in ten centres in China. In each centre, participants were stratified by age and randomly assigned by a random number table to receive one of several vaccine formulations or placebo. The study assessed eight formulations: split-virion formulation containing 7·5 μg, 15 μg, or 30 μg haemagglutinin per dose, with or without aluminium hydroxide adjuvant, and whole-virion formulation containing 5 μg or 10 μg haemagglutinin per dose, with adjuvant. All formulations were produced from the reassortant strain X-179A (A/California/07/2009-A/PR/8/34). We analysed the safety (adverse events), immunogenicity (geometric mean titre [GMT] of haemagglutination inhibition antibody), and seroprotection (GMT ≥1:40) of the formulations. Analysis was by per protocol. Two sites registered their trial with ClinicalTrials.gov, numbers NCT00956111 and NCT00975572. The other eight studies were registered with the State Food and Drug Administration of China. Findings: 12 691 participants received the first dose on day 0, and 12 348 participants received the second dose on day 21. The seroprotection rate 21 days after the first dose of vaccine ranged from 69·5% (95% CI 65·9-72·8) for the 7·5 μg adjuvant split-virion formulation to 92·8% (91·9-93·6) for the 30 μg non-adjuvant split-virion formulation. The seroprotection rate was 86·5% (796 of 920; 84·1-88·7) in recipients of one dose of the 7·5 μg non-adjuvant split-virion vaccine compared with 9·8% (140 of 1432; 8·3-11·4) in recipients of placebo (p<0·0001). One dose of the 7·5 μg non-adjuvant split-virion vaccine induced seroprotection in 178 of 232 children (aged 3 years to <12 years; 76·7%, 70·7-82·0), 211 of 218 adolescents (12 years to <18 years; 96·8%, 93·5-98·7), 289 of 323 adults (18-60 years; 89·5%, 85·6-92·6), and 118 of 147 adults older than 60 years (80·3%, 72·9-86·4), meeting the European Union's licensure criteria for seroprotection in all age-groups. In children, a second dose of the 7·5 μg formulation increased the seroprotection rate to 97·7% (215 of 220, 94·8-99·3). Adverse reactions were mostly mild or moderate, and self-limited. Severe adverse effects occurred in 69 (0·6%, 0·5-0·8) recipients of vaccine compared with one recipient (0·1%, 0-0·2) of placebo. The most common severe adverse reaction was fever, which occurred in 25 (0·22%; 0·14-0·33) recipients of vaccine after the first dose and four (0·04%; 0·01-0·09) recipients of vaccine after the second dose compared with no recipients of placebo after either dose. Interpretation: One dose of non-adjuvant split-virion vaccine containing 7·5 μg haemagglutinin could be promoted as the formulation of choice against 2009 pandemic influenza A H1N1 for people aged 12 years or older. In children (aged <12 years), two 7·5 μg doses might be needed. Funding: Sinovac Biotech, Hualan Biological Bacterin, China National Biotec Group, Beijing Tiantan Biological Products, Changchun Institute of Biological Products, Changchun Changsheng Life Sciences, Jiangsu Yanshen Biological Technology Stock, Zhejiang Tianyuan Bio-Pharmaceutical, Lanzhou Institute of Biological Products, Shanghai Institute of Biological Products, and Dalian Aleph Biomedical. © 2010 Elsevier Ltd. All rights reserved.

Li W.,Lanzhou Institute of Biological Products
Chinese Journal of Biologicals | Year: 2010

Objective: To isolate and identify enterovirus 71(EV71) Lanzhou01 strain, analyze its biological characteristics and lay a foundation of screening candidate virus strain of EV71 vaccine. Methods: EV71 Lanzhou01 strain was isolated from the fecal specimens of patients with hand-foot-and mouth disease in Lanzhou City, China for plaque cloning and subculture, then determined for specificity by RT-PCR and for virulence by Vero cell methyl cellulose plaque method. The VP1 gene of the isolated strain was cloned and sequenced, the virulence was determined, and the morphology was observed by scanning electron microscopy. The strain was inoculated to Vero cells at various MOIs, and the CPEs were observed, based on which a virus proliferation curve was plotted. The isolated strain was subcultured continuously and analyzed for VP1 gene and amino acid sequences to evaluate the genetic stability. Results: A isolated strain was obtained by subculture in cells and plaque cloning, of which the RT-PCR product showed a specific band at length of about 250 bp on 1% agarose gel electrophoretic profile. The strain was identified as EV71 of C4 subtype by VP1 gene sequencing and phylogenetic analysis, of which the homologies of nucleotides to the isolated EV71 strains in other regions including Zhejiang and Shenzhen were not less than 99%. The virus particles under electron microscope were in spherical forms, at diameters of 20-30 nm. The strain caused typical CPE of Vero cells, of which the virulence was 6. 8 LgPFU/ml. After subculture in Vero cells for 30 passages, the nucleotide homologies of VP1 gene of various passages were more than 99. 6%. However, no significant variation of amino acid sequence or significant change of virulence was observed. Conclusions: An EV71 strain with good biological characteristics was isolated, which laid a foundation of developing inactivated vaccine and screening candidate vaccine virus strain.

Objective: To develop a serum bactericidal assay(SBA) in vitro for determination of bactericidal activity of serum anti-Haemophilus influenzae type b (Hib) polyribosylribitol phosphate (PRP) antibody. Methods: A SBA method was developed by screening of complement and index bacterial strain, and verified for stability, specificity and precision. Results Hib-EAGAN strain as an index strain and Hib-positive serum showed high bactericidal specificity, of both of which the non-specific bactericidal rates were 0. of the four batches of complements provided by Pel-Freez, Lot 17830 showed high stability and specificity. The result of verification showed high stability and specificity of the developed Hib-SBA system, of which the CV of precision was 16%-28%. Conclusion: The SBA in vitro for determination of bactericidal activity of serum anti-Hib-PRP was successfully developed, which was of high-throughput, was time-saving and easy to be standardized.

Li P.,Lanzhou Institute of Biological Products
Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology | Year: 2011

To prepare the monoclonal antibody (mAb)against Pfs25 protein of Plasmodium falciparum, and establish the method of sandwich ELISA for detecting the Pfs25 protein. Pfs25 protein the recombinant expressed by Pichia pastoris was purified. The purified Pfs25 protein as the antigen was used to immune the BALB/c mice, The secreting specific mAb positive cell strains, which were prepared by hybridizing the Sp2/0 myeloma cell and the spleen cell from immunized mice, were detected by indirect ELISA method. The ascites of mAb were collected from immunization F1 mice, and their biological properties were identified by indirect ELISA. The anti-Pfs25 antibody was labeled by Horseradish Peroxidase (HRP), the sandwich ELISA method to detect Pfs25 protein was established based on the anti-Pfs25 mAb 4B7 and 1B4 as coating and enzyme antibody, respectively. Three hybridoma cell lines secreting mAb against Pfs25 protein have been selected from the antibody positive hybridizing cells. The two of them have a better stability and specificity. The sandwich ELISA method detecting Pfs25 protein was established. Its detecte range was 0.07-1 mg/mL , and its sensitivity was 41.6 ng/mL. The anti-Pfs25 mAb are successfully prepared and the double antibody sandwich ELISA method detecting Pfs25 protein is established. Our study lay a foundation of developing transmission-blocking malaria vaccine with Pfs25 protein as antigen.

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