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PubMed | National Vaccine & Serum Institute, University of Pennsylvania and National Institutes for Food and Drug Control
Type: | Journal: Virus research | Year: 2016

Mouse is one of the infection animal models for rotavirus. Since the optimal age of mouse sensitive to rotavirus infection thus far has not been unified, we elucidated clinical symptoms, immune responses and pathological changes of mice in different ages after challenged by murine rotavirus wild strain EDIM (Epidemic Diarrhea of Infant Mice) to provide data for the estimation. One-week-old, two-week-old, and three-week-old BALB/c mice were inoculated with EDIM in the challenge dose of 235 ID50, 470 ID50 and 705 ID50 respectively and were compared to mock-infected controls. Diarrhea illness, mobility, bodyweight were recorded, viral shedding and immune responses including serum IgA, fecal sIgA were detected, and small intestine tissue was evaluated for virus distribution and pathological changes. All the mice in one-week-old and two-week-old groups were completely unavoidable to be infected by EDIM and have been found to be malaise, activity reduced and even diarrhea, while three-week-old mice partly resist the challenge with 40% mice free from diarrhea. Meanwhile, EDIM infection has greater impact to the bodyweight of two-week-old group than those of one-week-old, three-week-old (0.9860 vs 1.2340, 1.2375g/day). One peak of virus shedding in three groups was observed in day 1-2 post infection, but the duration shortened with age increase. Feces sIgA in both two-week-old and three-week-old groups began to increase in day 4, 2-3days earlier than that in one-week-old group, and grow to the peak in day 8, which is about 2 fold of that in one-week-old group. Stronger serum IgA response was found in two-week-old group, it increased to the peak in day 15 and the level was 2 fold of three-week-old group and 4 fold of one-week-old group. The pathological changes included vacuolar degeneration, edema and congestion of intestinal wall, integrity destruction of enteric epithelium, and the changes relieved with the increase of age. Besides, rotavirus particles were found in small intestine tissues, especially in the surface and crypt of villi. In conclusion, the two-week-old mice were more sensitive to EDIM infection and initiated more effective immune response. In combination with that 14days old mice equals to 2 months infant when the first dose of rotavirus vaccine should be administrated, two-week-old mice is preferred to be used as infection model for the study of pathogenicity and immunogenicity of rotavirus.


Liu Y.,National Vaccine Serum Institute | Wang X.-X.,National Vaccine Serum Institute | Song D.-M.,National Vaccine Serum Institute | Wen Z.-H.,National Vaccine Serum Institute | And 3 more authors.
Chinese Journal of Biologicals | Year: 2014

Objective To validate the suitability and apply TaqMan MGB probe real-time quantitative PCR for the detection of residual DNA in Vero cells. Methods The TaqMan MGB probe real-time quantitative PCR was validated for specificity, sensitivity, precision and accuracy, and used for detection of residual Vero cell DNA contents in three batches of concentrated, purified and bulk poliovirus, based on which the removal rate of residual Vero cell DNA was calculated. Results The Vero cell genomic DNA long tandem repeats were amplified by the developed TaqMan MGB probe real-time quantitative PCR specifically. Standard curve showed good linearity within a DNA concentration range of 10-1 - 10-6 ng/μl, with a correlation coefficient ( R2 value) of 0. 996 and an amplification efficacy of 93. 54%. The sensitivity of the developed method was 10-6 ng /μl, which was higher than that of dot blot. The coefficients of variation ( CVs ) of determination results of positive control DNA templates at high ( 10-2 ng/μl), moderate ( 10-4 ng /μl ) and low (10-6 ng/ μl) concentrations in intra-assay were 0. 145% ∼ 3. 110%, while those in inter-assay were 0. 624% ∼ 2.359%, respectively. The recovery rates of positive control DNA at various concentrations were 101. 5% ~ 109. 4%, which were within the receptible range. The result of residual Vero cell DNA concentration detected by TaqMan MGB probe real-time quantitative PCR was in line with that by dot blot within the sensitivity range. The total removal rate of residual Vero cell DNA in three batches of inactivated polio vaccine after purification was nearly 100%. Conclusion TaqMan probe realtime quantitative PCR assay showed high specificity, precision, accuracy and sensitivitv, which may be used for in-house quality control of residual Vero cell DNA instead of dot blot hybridization.


Wang J.,National Vaccine & Serum Institute
Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology | Year: 2011

To establish the method to detect the cellular immune response of enhanced hepatitis B vaccine and make verification preliminary. Immunized BALB/c mice with enhanced hepatitis B vaccine and detected the IFN-gamma spots forming cells (SFC) of mouse spleen cell by Elispot. Optimized the conditions of the experiment. Cellular immune response between enhanced hepatitis B vaccine and normal hepatitis B vaccine by Elispot were compared. IFN-gamma SFC was higher in 5microg dose than in 2microg dose after immunization with enhanced hepatitis B vaccine and IFN-gamma SFC was declined after immunization 3 weeks ago. IFN-gamma SFC was higher in stimulus by peptide than by protein. Compared to normal hepatitis B vaccine, IFN-gamma SFC was higher in enhanced hepatitis B vaccine. Established the detection method to evaluate the cellular immunity of enhanced hepatitis B vaccine and tested the repeatability.


PubMed | National Vaccine & Serum Institute
Type: Evaluation Studies | Journal: Zhonghua shi yan he lin chuang bing du xue za zhi = Zhonghua shiyan he linchuang bingduxue zazhi = Chinese journal of experimental and clinical virology | Year: 2011

To establish the method to detect the cellular immune response of enhanced hepatitis B vaccine and make verification preliminary.Immunized BALB/c mice with enhanced hepatitis B vaccine and detected the IFN-gamma spots forming cells (SFC) of mouse spleen cell by Elispot. Optimized the conditions of the experiment. Cellular immune response between enhanced hepatitis B vaccine and normal hepatitis B vaccine by Elispot were compared.IFN-gamma SFC was higher in 5microg dose than in 2microg dose after immunization with enhanced hepatitis B vaccine and IFN-gamma SFC was declined after immunization 3 weeks ago. IFN-gamma SFC was higher in stimulus by peptide than by protein. Compared to normal hepatitis B vaccine, IFN-gamma SFC was higher in enhanced hepatitis B vaccine.Established the detection method to evaluate the cellular immunity of enhanced hepatitis B vaccine and tested the repeatability.


PubMed | National Vaccine & Serum Institute and Liaoning Medical University
Type: | Journal: Journal of nanobiotechnology | Year: 2015

Active targeting endocytosis mediated by the specific interaction between folic acid and its receptor has been a hotspot in biological therapy of many human cancers. Various studies have demonstrated that folate and its conjugates could facilitate the chemotherapeutic drug delivery into folate receptor (FR)-positive tumor cells in vitro and in vivo. In order to utilize FA-FR binding specificity to achieve targeted delivery of drugs into tumor cells, we prepared Gefitinib loaded folate decorated bovine serum albumin conjugated carboxymethyl--cyclodextrin nanoparticles for enhancing drug delivery in cancer cells. On this context, the aim of our study was to develop a novel nano-delivery system for promoting tumor-targeting drug delivery in folate receptor-positive Hela cells.We prepared folic acid (FA)-decorated bovine serum albumin (BSA) conjugated carboxymethyl--cyclodextrin (CM--CD) nanoparticles (FA-BSA-CM--CD NPs) capable of entrapping a hydrophobic Gefitinib. It was observed that nanoparticles are monodisperse and spherical nanospheres with an average diameter of 90.2nm and negative surface charge of -18.6mV. FA-BSA-CM--CD NPs could greatly facilitate Gefitinib uptake and enhance the toxicity to folate receptor-positive Hela cells. Under the reaction between FA and FR, Gefitinib loaded FA-BSA-CM--CD NPs induced apoptosis of Hela cells through elevating the expression of caspase-3 and inhibited autophagy through decreasing the expressing of LC3. It also confirmed that clathrin-mediated endocytosis and macropinocytosis exerted great influence on the internalization of both NPs.These results demonstrated that FA may be an effective targeting molecule and FA-BSA-CM--CD NPs provided a new strategy for the treatment of human cancer cells which over-expressed folate receptors.

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