AIM: To establish the safety and efficacy of an indigenously developed r-hepatitis B vaccine using an accelerated schedule and to highlight the social awareness and commitment in preventing the spreading of hepatitis ...AIM: To establish the safety and efficacy of an indigenously developed r-hepatitis B vaccine using an accelerated schedule and to highlight the social awareness and commitment in preventing the spreading of hepatitis B virus infection. METHODS: The study was a multicentric, double blind, randomized (3:1) study using three doses of vaccine immunization schedule (20μg for those above 10 years old and 10 μg for those below 10 years old) on d 0, 30 and 60. One hundred and sixty-six subjects were enrolled (87 males and 76 females aged 5-35 years). The main outcome measure was assessment of immunogenicity and safety. RESULTS: A 100% seroconversion response was observed on the 30th d after the 1st injection in both the experimental groups. The sero-protection data reported a 41.2-65.6% response on the 30th d after the 1st injection and reached 100% on the 60th d. Descriptive statistical analysis showed a geometric mean titer value of 13.77 mIU/mL in the test (BEVAC) group and 10.95 mlU/mL in the commercial control (ENGERIX-B) group on the 30th d after the 1st injection. The response on the 60th d showed a geometric mean titre value (GMT) of 519.84 mlU/mL in the BEVAC group and 475.46 mlU/mL in the ENGERIX-B group. On the 90th d, the antibody titer response was observed to be 2627.58 mlU/mL in the BEVAC group and 2272.72 mlU/mL in the ENGERIX-B group. Two subjects in each group experienced pains at injection site after the first vaccination. A total of six subjects in both groups experienced a solicited adverse reaction, which included pains, swelling and redness at the injection site, three subjects in the group-B had a pain at the injection site after the third dose. No other serious adverse events occurred and no dose-related local or general symptoms were observed during the study. CONCLUSION: The vaccine is safe, efficacious and immunogenic in comparison with the well documented ENGERIX-B.展开更多
This paper presents the results of a pre-clinical study of the immunogenicity and efficacy of an egg-derived, inactivated, whole-virion adjuvanted vaccine (Refluvac) on ferret models. For this purpose, groups of eig...This paper presents the results of a pre-clinical study of the immunogenicity and efficacy of an egg-derived, inactivated, whole-virion adjuvanted vaccine (Refluvac) on ferret models. For this purpose, groups of eight ferrets (6 to 7 months old) were injected with 0.5 mL of vaccine specimens containing 3.75, 7.5 or 15.0 μg of virus hemagglutinin. Administration was intramuscular and given either as a single dose or as two doses 14 days apart. All vaccine specimens manifested immunogenicity in ferrets for single (HI titer, from 51 ± 7 to 160 ± 23) and double (HI titer, from 697± 120 to 829 ± 117) administrations. To assess the protective effects of the vaccine, ferrets from the vaccinated and control groups were infected intranasally with pandemic virus A/California/7/09 (H1N1) pdm09 at a dose of 106 106/0.5 mL. Fourteen days post-infection, the ferrets inoculated with single or double vaccines containing 3.75, 7.5 or 15.0 ~g of hemagglutinin per dose showed no signs of influenza infection, weight loss, or body temperature rise, and no premature deaths occurred. The number of vaccinated ferrets shedding the virus via the upper airway, as well as the amount of virus shed after infection, was significantly reduced in comparison with animals from the control group. Based on our results, we suggest that a single vaccination at a dose of 3.75 or 7.5 μg hemagglutinin be used for Phase I clinical trials.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
AIM: Patients with chronic hepatitis C have been recommended to receive vaccinations against hepatitis B. Our study aimed at evaluating the hepatitis B immunogenicity and efficacy against hepatitis B virus infection 4...AIM: Patients with chronic hepatitis C have been recommended to receive vaccinations against hepatitis B. Our study aimed at evaluating the hepatitis B immunogenicity and efficacy against hepatitis B virus infection 4 years after primary immunization series in a group of patients with chronic hepatitis C.METHODS: We recruited 36 out of 48 hepatitis C virus (HCV) infected individuals who were vaccinated against hepatitis B virus (20 μg of recombinant HBsAg at 0-1-6mo schedule) in 1998. Here we measured anti-HBs titers and anti-HBc 4 years after delivery of the third dose of primary immunization series.RESULTS: After 4 years a total of 13/36 (36%) HCV infected patients had seroprotective titers of anti-HBs compared with 9/10 (90%) in the control group, (P<0.05).Similarly the mean concentration of anti-HBs found in hepatitis C patients was significantly lower than that found in healthy subjects (18.3 and 156.0 mIU/mL respectively (P<0.05). None of the HCV infected patients or controls became infected with HBV during the study period as confirmed by anti-HBc negativity.CONCLUSION: We demonstrated that 4 years after HBV immunizations' more than 60% of vaccinated HCV patients did not maintain seroprotective levels of anti-HBs, which might put them at risk of clinically significant breakthrough infections. Further follow-up studies are required to clarify whether memory B and T lymphocytes can provideprotection in chronic hepatitis C patients in the absence or inadequate titers of anti-HBs.展开更多
AIM:To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori (H pylori) and to study the immunogenicity of adhesin AlpA. METHODS: Gene Ab, which was amplified from H pylori chromosomal DNA...AIM:To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori (H pylori) and to study the immunogenicity of adhesin AlpA. METHODS: Gene Ab, which was amplified from H pylori chromosomal DNA by PCR technique, was sequenced and the biological information was analyzed, and inserted into the Nco I and Not I restriction fragments of the expression vector pET-22b(+) using T4 DNA ligase. The resulting plasmid pET-AlpA was transformed into competent E.coli BL21(DE3) cells using ampicillin resistance for selection. Recombinant strains were incubated in 5 mL LB with 100 μg/mL ampicillin overnight at 37 ℃. Sonication of BL21(DE3)pET-22b(+)/AlpA was analyzed by Western blot to detect AlpA immunogenicity. RESULTS: The gene encoding AlpA protein was amplified by PCR with chromosomal DNA of H pylori Sydney strain (SS1) as templates. It revealed that AlpA DNA fragment amplified by PCR had approximately 1 500 nucleotides, compatible with the previous reports. The recombinant plasmid pET-22b(+)/AB was successfully constructed. DNA sequencing showed one open reading frame with the length of 588 bp. It encoded seven conservative regions that showed good antigenicity and hydrophobicity by Parker and Welling method. Furthermore, INTERNET EXPASY, NNPREDICT and ISREC predicted that it was a porin-like structure consisting of β-pleated sheets that were embedded in the outer membrane. BLAST analyzed 836 767 protein sequences and found that the similar sequences were all belonging to H pylori OMP sequences. SDS-PAGE and scan analysis showed that the molecular weight of AB was 22.5 ku and recombinant protein amounted to 29% of the total bacterial protein, among which dissolved expression amounted to 21.9% of sonicated supernatant. The rAB purity amounted to 96% through affinity chromatography. Western blot analysis of rAB confirmed that it could be specially recognized by serum form rabbit immunized with AlpA and H pylori infected. CONCLUSION: Adhesin AlpA recombinant protein may be a potential vaccine for control and treatment of H pylori infection.展开更多
The present study deals with the co-ordination of cytokine (IL-4 and IFN-7) expression and kinetics of peste des petits ruminants (PPR) virus antigen and antibody in PPRV infected and vaccinated goats. The infecte...The present study deals with the co-ordination of cytokine (IL-4 and IFN-7) expression and kinetics of peste des petits ruminants (PPR) virus antigen and antibody in PPRV infected and vaccinated goats. The infected animals exhibited mixed cytokine (both TH1 and TH2) responses in the initial phase of the disease. The infected and dead goats had increased IFN-T response before their death; while IL-4 remained at the base level. The cytokine expression in recovered animals was almost similar to that of vaccinated ones, where a unique biphasic response of IL-4 expression was observed with an up-regulation of IFN-T on 7th days post vaccination (dpv). Analysis of PPR virus antigen and antibody kinetics in different components of blood from infected and vaccinated animais revealed that the PPR virus antigen load was highest in plasma followed by serum and blood of the infected animals, whereas vaccinated animals showed only marginal positivity on 9th dpv. The antibody titer was high in serum followed by plasma and blood in both vaccinated and infected animals. Therefore, it is inferred that the presence of antigen and antibody were significant with the expression of cytokine, and that a decreased response of IL-4 was noticed during intermediate phase of the disease i.e., 7 to 12m days post infection (dpi). This indicates the ability to mount a functional TH2 response after 14th dpi could be a critical determinant in deciding the survival of the PPR infected animal.展开更多
The aim of this study is to investigate the feasibility and mechanism of hIL-2-preS DNA vaccine as prevention and therapeutic approach against Hepatitis B. Eukaryon expression vector involving hIL-2 and preS gene was ...The aim of this study is to investigate the feasibility and mechanism of hIL-2-preS DNA vaccine as prevention and therapeutic approach against Hepatitis B. Eukaryon expression vector involving hIL-2 and preS gene was constructed with recombinant technique and transferred into normal BALB/c mice and HBV transgenic mice (Tg-Mice) respectively. Then a series of detection were performed: detection of anti-preS2, HBs antibody and HBsAg in BALB/c mice and Tg-mice with ELISA, quantification of HBV DNA copies in HBV Tg-mice serum with real-time PCR, determination of hepatitis degree with immunopathological HE staining and detection of liver function. Anti-preS1 can be detected at 4 th , 6 th and 10 th week in inoculated BALB/c mice. Injection with gene gun gained an advantage over muscular and subcutaneous injection since it acquired just 1/10 inoculation quantity (10 μg/mouse). Highest expression of IgG2a at 4 th week suggested Th1-mediated immune response, which facilitated HBV cleaning. Of all inoculated HBV Tg-mice, 80% of them showed anti-preS2, HBs antibody positive and HBV DNA decreased, and 20% showed negative for HBsAg. HE staining to hepatic tissue showed obvious infiltration of inflammatory cells, swelling and granular degeneration of hepatocytes. In our study, IL-2-preS DNA vaccine which can provoke the humoral and cellular immune response and break the immune tolerance supports the designation and construction of new vaccine against HBV and specific immune remedy for HBV continuous infection.展开更多
基金Supported by the Biological E Limited, Hyderabad, India
文摘AIM: To establish the safety and efficacy of an indigenously developed r-hepatitis B vaccine using an accelerated schedule and to highlight the social awareness and commitment in preventing the spreading of hepatitis B virus infection. METHODS: The study was a multicentric, double blind, randomized (3:1) study using three doses of vaccine immunization schedule (20μg for those above 10 years old and 10 μg for those below 10 years old) on d 0, 30 and 60. One hundred and sixty-six subjects were enrolled (87 males and 76 females aged 5-35 years). The main outcome measure was assessment of immunogenicity and safety. RESULTS: A 100% seroconversion response was observed on the 30th d after the 1st injection in both the experimental groups. The sero-protection data reported a 41.2-65.6% response on the 30th d after the 1st injection and reached 100% on the 60th d. Descriptive statistical analysis showed a geometric mean titer value of 13.77 mIU/mL in the test (BEVAC) group and 10.95 mlU/mL in the commercial control (ENGERIX-B) group on the 30th d after the 1st injection. The response on the 60th d showed a geometric mean titre value (GMT) of 519.84 mlU/mL in the BEVAC group and 475.46 mlU/mL in the ENGERIX-B group. On the 90th d, the antibody titer response was observed to be 2627.58 mlU/mL in the BEVAC group and 2272.72 mlU/mL in the ENGERIX-B group. Two subjects in each group experienced pains at injection site after the first vaccination. A total of six subjects in both groups experienced a solicited adverse reaction, which included pains, swelling and redness at the injection site, three subjects in the group-B had a pain at the injection site after the third dose. No other serious adverse events occurred and no dose-related local or general symptoms were observed during the study. CONCLUSION: The vaccine is safe, efficacious and immunogenic in comparison with the well documented ENGERIX-B.
文摘This paper presents the results of a pre-clinical study of the immunogenicity and efficacy of an egg-derived, inactivated, whole-virion adjuvanted vaccine (Refluvac) on ferret models. For this purpose, groups of eight ferrets (6 to 7 months old) were injected with 0.5 mL of vaccine specimens containing 3.75, 7.5 or 15.0 μg of virus hemagglutinin. Administration was intramuscular and given either as a single dose or as two doses 14 days apart. All vaccine specimens manifested immunogenicity in ferrets for single (HI titer, from 51 ± 7 to 160 ± 23) and double (HI titer, from 697± 120 to 829 ± 117) administrations. To assess the protective effects of the vaccine, ferrets from the vaccinated and control groups were infected intranasally with pandemic virus A/California/7/09 (H1N1) pdm09 at a dose of 106 106/0.5 mL. Fourteen days post-infection, the ferrets inoculated with single or double vaccines containing 3.75, 7.5 or 15.0 ~g of hemagglutinin per dose showed no signs of influenza infection, weight loss, or body temperature rise, and no premature deaths occurred. The number of vaccinated ferrets shedding the virus via the upper airway, as well as the amount of virus shed after infection, was significantly reduced in comparison with animals from the control group. Based on our results, we suggest that a single vaccination at a dose of 3.75 or 7.5 μg hemagglutinin be used for Phase I clinical trials.
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.
文摘AIM: Patients with chronic hepatitis C have been recommended to receive vaccinations against hepatitis B. Our study aimed at evaluating the hepatitis B immunogenicity and efficacy against hepatitis B virus infection 4 years after primary immunization series in a group of patients with chronic hepatitis C.METHODS: We recruited 36 out of 48 hepatitis C virus (HCV) infected individuals who were vaccinated against hepatitis B virus (20 μg of recombinant HBsAg at 0-1-6mo schedule) in 1998. Here we measured anti-HBs titers and anti-HBc 4 years after delivery of the third dose of primary immunization series.RESULTS: After 4 years a total of 13/36 (36%) HCV infected patients had seroprotective titers of anti-HBs compared with 9/10 (90%) in the control group, (P<0.05).Similarly the mean concentration of anti-HBs found in hepatitis C patients was significantly lower than that found in healthy subjects (18.3 and 156.0 mIU/mL respectively (P<0.05). None of the HCV infected patients or controls became infected with HBV during the study period as confirmed by anti-HBc negativity.CONCLUSION: We demonstrated that 4 years after HBV immunizations' more than 60% of vaccinated HCV patients did not maintain seroprotective levels of anti-HBs, which might put them at risk of clinically significant breakthrough infections. Further follow-up studies are required to clarify whether memory B and T lymphocytes can provideprotection in chronic hepatitis C patients in the absence or inadequate titers of anti-HBs.
基金Supported by the National Natural Science Foundation of China,No. 30270078
文摘AIM:To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori (H pylori) and to study the immunogenicity of adhesin AlpA. METHODS: Gene Ab, which was amplified from H pylori chromosomal DNA by PCR technique, was sequenced and the biological information was analyzed, and inserted into the Nco I and Not I restriction fragments of the expression vector pET-22b(+) using T4 DNA ligase. The resulting plasmid pET-AlpA was transformed into competent E.coli BL21(DE3) cells using ampicillin resistance for selection. Recombinant strains were incubated in 5 mL LB with 100 μg/mL ampicillin overnight at 37 ℃. Sonication of BL21(DE3)pET-22b(+)/AlpA was analyzed by Western blot to detect AlpA immunogenicity. RESULTS: The gene encoding AlpA protein was amplified by PCR with chromosomal DNA of H pylori Sydney strain (SS1) as templates. It revealed that AlpA DNA fragment amplified by PCR had approximately 1 500 nucleotides, compatible with the previous reports. The recombinant plasmid pET-22b(+)/AB was successfully constructed. DNA sequencing showed one open reading frame with the length of 588 bp. It encoded seven conservative regions that showed good antigenicity and hydrophobicity by Parker and Welling method. Furthermore, INTERNET EXPASY, NNPREDICT and ISREC predicted that it was a porin-like structure consisting of β-pleated sheets that were embedded in the outer membrane. BLAST analyzed 836 767 protein sequences and found that the similar sequences were all belonging to H pylori OMP sequences. SDS-PAGE and scan analysis showed that the molecular weight of AB was 22.5 ku and recombinant protein amounted to 29% of the total bacterial protein, among which dissolved expression amounted to 21.9% of sonicated supernatant. The rAB purity amounted to 96% through affinity chromatography. Western blot analysis of rAB confirmed that it could be specially recognized by serum form rabbit immunized with AlpA and H pylori infected. CONCLUSION: Adhesin AlpA recombinant protein may be a potential vaccine for control and treatment of H pylori infection.
文摘The present study deals with the co-ordination of cytokine (IL-4 and IFN-7) expression and kinetics of peste des petits ruminants (PPR) virus antigen and antibody in PPRV infected and vaccinated goats. The infected animals exhibited mixed cytokine (both TH1 and TH2) responses in the initial phase of the disease. The infected and dead goats had increased IFN-T response before their death; while IL-4 remained at the base level. The cytokine expression in recovered animals was almost similar to that of vaccinated ones, where a unique biphasic response of IL-4 expression was observed with an up-regulation of IFN-T on 7th days post vaccination (dpv). Analysis of PPR virus antigen and antibody kinetics in different components of blood from infected and vaccinated animais revealed that the PPR virus antigen load was highest in plasma followed by serum and blood of the infected animals, whereas vaccinated animals showed only marginal positivity on 9th dpv. The antibody titer was high in serum followed by plasma and blood in both vaccinated and infected animals. Therefore, it is inferred that the presence of antigen and antibody were significant with the expression of cytokine, and that a decreased response of IL-4 was noticed during intermediate phase of the disease i.e., 7 to 12m days post infection (dpi). This indicates the ability to mount a functional TH2 response after 14th dpi could be a critical determinant in deciding the survival of the PPR infected animal.
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 30271213)
文摘The aim of this study is to investigate the feasibility and mechanism of hIL-2-preS DNA vaccine as prevention and therapeutic approach against Hepatitis B. Eukaryon expression vector involving hIL-2 and preS gene was constructed with recombinant technique and transferred into normal BALB/c mice and HBV transgenic mice (Tg-Mice) respectively. Then a series of detection were performed: detection of anti-preS2, HBs antibody and HBsAg in BALB/c mice and Tg-mice with ELISA, quantification of HBV DNA copies in HBV Tg-mice serum with real-time PCR, determination of hepatitis degree with immunopathological HE staining and detection of liver function. Anti-preS1 can be detected at 4 th , 6 th and 10 th week in inoculated BALB/c mice. Injection with gene gun gained an advantage over muscular and subcutaneous injection since it acquired just 1/10 inoculation quantity (10 μg/mouse). Highest expression of IgG2a at 4 th week suggested Th1-mediated immune response, which facilitated HBV cleaning. Of all inoculated HBV Tg-mice, 80% of them showed anti-preS2, HBs antibody positive and HBV DNA decreased, and 20% showed negative for HBsAg. HE staining to hepatic tissue showed obvious infiltration of inflammatory cells, swelling and granular degeneration of hepatocytes. In our study, IL-2-preS DNA vaccine which can provoke the humoral and cellular immune response and break the immune tolerance supports the designation and construction of new vaccine against HBV and specific immune remedy for HBV continuous infection.