[Objective] The aim of this study was to improve the purification and protective potency of HP-PRRS inactivated vaccine. [Method] HP-PRRS virus that had been multiplied inside Marc-145 cells was collected and concentr...[Objective] The aim of this study was to improve the purification and protective potency of HP-PRRS inactivated vaccine. [Method] HP-PRRS virus that had been multiplied inside Marc-145 cells was collected and concentrated 50 times and then inactivated. Complete virions were separated and collected by chromatography with Sepharose 4 Fast Flow. Oil adjuvant was added to prepare purified inactivated vaccine. [Result] Viral protein was separated from other proteins by purification and the viral protein contents ranged from 76.7% to 82.4%, and 96% of the expected serum proteins were removed. Protective potency of purified vaccine was above 4/5 and positive conversion rate of antibody was over 86%, both higher than that of unpurified vaccine. The differences were significant. [Conclusion] The experiment il-lustrated that the immune efficacy of vaccine can be enhanced through concentrat- ing and purifying, while the non-viral protein can be removed, so that allergic reaction and stress response cadsed by vaccine inoculation can be avoided.展开更多
The poliomyelitis is an acute infection produced by the polio virus that affects the human central nervous system. It is transmitted by fecal-oral and respiratory contact.There are two types of vaccine, OPV （live att...The poliomyelitis is an acute infection produced by the polio virus that affects the human central nervous system. It is transmitted by fecal-oral and respiratory contact.There are two types of vaccine, OPV （live attenuated virus） and IPV （inactivated polio virus）. Currently, there is a plan of vaccination until the age of 5 with OPV. The children vaccinated expel a virus （derived from the vaccine） to the environment, and some of the people that have oral contact with them, get vaccinated by the herd behavior. Nevertheless, taking into account the lately observed facts about the reversion to virulence of the oral polio vaccine during its circulation in the environment, a change in the current vaccination schedule is being contemplated, where the oral polio vaccine can be replaced by the inactivated vaccine. Nowadays, In Colombia the inactivated oral polio vaccine is recommended for children presenting immune deficiency who are vaccinated with IPV. These children do not expel poliovirus to the environment. This work presents a mathematical model that describes the dynamics of the infection in a population where the two types of vaccination are carried out. The population is divided into two groups of age and Michaelis-Menten interactions. Different strategies of vaccination are simulated and analyzed.展开更多
Porcine reproductive and respiratory syndrome （PRRS） is the severest disease of pigs worldwide, caused by a highly genetically diverse RNA virus, called Porcine reproductive and respiratory syndrome virus （PRRSV）....Porcine reproductive and respiratory syndrome （PRRS） is the severest disease of pigs worldwide, caused by a highly genetically diverse RNA virus, called Porcine reproductive and respiratory syndrome virus （PRRSV）. The research summarized the genome characteristics of PRRSV particles and the most updated knowledge of structure protein function, and introduced the intellectual of PRRSV transmission and host immune response, which is very important for prevention and control for PRRS. A report showed that mass vaccination can stabilize the immunity of the entire herd, and this is the first required step for a PRRS eradication plan. However, the attenuated live vaccines may not achieve a valid prevention. The final goal of the EU project is to develop new generation, efficacious and safe maker vaccines that can be adapted to temporary changes and geographical differences.Robinson reported that broadly antibodies could neutralize all rapidly evolving type Ⅰ and type Ⅱ viruses, while further studies are expected to elucidate mechanisms of neutralizing antibody production and maturation and to investigate conserved epitope targets of cross-neutralization in this rapidly evolving virus.展开更多
Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement （i.e., accuracy and correc...Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement （i.e., accuracy and correctness）, and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material （pilot vaccine）. The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias （random error）, and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken＇s embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine （MRIL）, with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.展开更多
OBJECTIVE: To evaluate the immunogenicity, safety, and dosage of a new inactivated hepatitis A vaccine administered to young adults. METHODS: One hundred and four normal adult volunteers, seronegative for hepatitis A ...OBJECTIVE: To evaluate the immunogenicity, safety, and dosage of a new inactivated hepatitis A vaccine administered to young adults. METHODS: One hundred and four normal adult volunteers, seronegative for hepatitis A virus and hepatitis B surface antigen, were randomly assigned to one of three groups. The high-dose group received a primary dose of 1000 units of the new vaccine, the low-dose group received a primary dose of 500 units of the same vaccine, and the Havrix group received a primary dose of 1440 enzyme-linked immunosorbent assay units of Havrix, a licensed inactivated hepatitis A vaccine. All groups received a booster dose of the same vaccine 6 months after the primary dose. Local and systemic adverse reactions, seroconversion rates, and geometric mean titers of hepatitis A virus antibodies were measured in all three groups. RESULTS: Local and systemic reaction types and rates were similar in all three groups after primary and booster doses, although local reactions were more frequent in the Havrix group following the primary dose. No serious adverse reactions occurred. One month after the primary dose, the seroconversion rate was 87.5% in the high-dose group, 70.0% in the low-dose group, and 50.0% in the Havrix group (P = 0.001, versus the high-dose group). At month 6 (before administration of the booster dose), seroconversion rates were 96.9% in the high-dose group, 65.0% in the low-dose group (P = 0.0029), and 68.8% in the Havrix group (P = 0.007). All subjects in all groups seroconverted by one month after receipt of the booster dose. Geometric mean titers were similar in all three groups at month 1, but were higher in the high-dose group (264 mIU/ml) than those in the Havrix group (135 mIU/ml) at month 6 (P = 0.0013). One month after the booster dose, geometric mean titers in the high-dose group (2747 mIU/ml) were higher than those in the low-dose group (1657 mIU/ml) (P = 0.0223) or in the Havrix group (1316 mIU/ml) (P = 0.01). CONCLUSIONS: This new inactivated hepatitis A vaccine is immunogenic and safe; two doses of either 500 or 1000 units can induce hepatitis A virus antibodies well above the protection level.展开更多
基金Supported by Science and Technical Development Plan of Jilin City(2013210029)Fund for Supporting Key Subjects in Jilin Agricultural Science and Technology College(2013x023)~~
文摘[Objective] The aim of this study was to improve the purification and protective potency of HP-PRRS inactivated vaccine. [Method] HP-PRRS virus that had been multiplied inside Marc-145 cells was collected and concentrated 50 times and then inactivated. Complete virions were separated and collected by chromatography with Sepharose 4 Fast Flow. Oil adjuvant was added to prepare purified inactivated vaccine. [Result] Viral protein was separated from other proteins by purification and the viral protein contents ranged from 76.7% to 82.4%, and 96% of the expected serum proteins were removed. Protective potency of purified vaccine was above 4/5 and positive conversion rate of antibody was over 86%, both higher than that of unpurified vaccine. The differences were significant. [Conclusion] The experiment il-lustrated that the immune efficacy of vaccine can be enhanced through concentrat- ing and purifying, while the non-viral protein can be removed, so that allergic reaction and stress response cadsed by vaccine inoculation can be avoided.
文摘The poliomyelitis is an acute infection produced by the polio virus that affects the human central nervous system. It is transmitted by fecal-oral and respiratory contact.There are two types of vaccine, OPV （live attenuated virus） and IPV （inactivated polio virus）. Currently, there is a plan of vaccination until the age of 5 with OPV. The children vaccinated expel a virus （derived from the vaccine） to the environment, and some of the people that have oral contact with them, get vaccinated by the herd behavior. Nevertheless, taking into account the lately observed facts about the reversion to virulence of the oral polio vaccine during its circulation in the environment, a change in the current vaccination schedule is being contemplated, where the oral polio vaccine can be replaced by the inactivated vaccine. Nowadays, In Colombia the inactivated oral polio vaccine is recommended for children presenting immune deficiency who are vaccinated with IPV. These children do not expel poliovirus to the environment. This work presents a mathematical model that describes the dynamics of the infection in a population where the two types of vaccination are carried out. The population is divided into two groups of age and Michaelis-Menten interactions. Different strategies of vaccination are simulated and analyzed.
基金Supported by the Natural Science Research Subject of Minhang Center(2015MHZ041)
文摘Porcine reproductive and respiratory syndrome （PRRS） is the severest disease of pigs worldwide, caused by a highly genetically diverse RNA virus, called Porcine reproductive and respiratory syndrome virus （PRRSV）. The research summarized the genome characteristics of PRRSV particles and the most updated knowledge of structure protein function, and introduced the intellectual of PRRSV transmission and host immune response, which is very important for prevention and control for PRRS. A report showed that mass vaccination can stabilize the immunity of the entire herd, and this is the first required step for a PRRS eradication plan. However, the attenuated live vaccines may not achieve a valid prevention. The final goal of the EU project is to develop new generation, efficacious and safe maker vaccines that can be adapted to temporary changes and geographical differences.Robinson reported that broadly antibodies could neutralize all rapidly evolving type Ⅰ and type Ⅱ viruses, while further studies are expected to elucidate mechanisms of neutralizing antibody production and maturation and to investigate conserved epitope targets of cross-neutralization in this rapidly evolving virus.
文摘Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement （i.e., accuracy and correctness）, and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material （pilot vaccine）. The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias （random error）, and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken＇s embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine （MRIL）, with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.
文摘OBJECTIVE: To evaluate the immunogenicity, safety, and dosage of a new inactivated hepatitis A vaccine administered to young adults. METHODS: One hundred and four normal adult volunteers, seronegative for hepatitis A virus and hepatitis B surface antigen, were randomly assigned to one of three groups. The high-dose group received a primary dose of 1000 units of the new vaccine, the low-dose group received a primary dose of 500 units of the same vaccine, and the Havrix group received a primary dose of 1440 enzyme-linked immunosorbent assay units of Havrix, a licensed inactivated hepatitis A vaccine. All groups received a booster dose of the same vaccine 6 months after the primary dose. Local and systemic adverse reactions, seroconversion rates, and geometric mean titers of hepatitis A virus antibodies were measured in all three groups. RESULTS: Local and systemic reaction types and rates were similar in all three groups after primary and booster doses, although local reactions were more frequent in the Havrix group following the primary dose. No serious adverse reactions occurred. One month after the primary dose, the seroconversion rate was 87.5% in the high-dose group, 70.0% in the low-dose group, and 50.0% in the Havrix group (P = 0.001, versus the high-dose group). At month 6 (before administration of the booster dose), seroconversion rates were 96.9% in the high-dose group, 65.0% in the low-dose group (P = 0.0029), and 68.8% in the Havrix group (P = 0.007). All subjects in all groups seroconverted by one month after receipt of the booster dose. Geometric mean titers were similar in all three groups at month 1, but were higher in the high-dose group (264 mIU/ml) than those in the Havrix group (135 mIU/ml) at month 6 (P = 0.0013). One month after the booster dose, geometric mean titers in the high-dose group (2747 mIU/ml) were higher than those in the low-dose group (1657 mIU/ml) (P = 0.0223) or in the Havrix group (1316 mIU/ml) (P = 0.01). CONCLUSIONS: This new inactivated hepatitis A vaccine is immunogenic and safe; two doses of either 500 or 1000 units can induce hepatitis A virus antibodies well above the protection level.
