AIM: To characterize the biochemical and immunological properties of an experimental ISCOMS vaccine prepared from a novel therapeutic polypeptide based on T cell epitopes of HBsAg, and a heptatis B-ISCOMS was prepared...AIM: To characterize the biochemical and immunological properties of an experimental ISCOMS vaccine prepared from a novel therapeutic polypeptide based on T cell epitopes of HBsAg, and a heptatis B-ISCOMS was prepared and investigated. METHODS: An immunostimulating complexes(ISCOMS)-based vaccine containing a novel therapeutic hepatitis B polypeptide was prepared by dialysis method, and its formation was visualized by electron microscopy and biochemically verified by SDS-polyacrylamide gel electrophoresis. Amount of the peptide within ISCOMS was determined by Bradford assay, and specific CTL response was detected by ELISPOT assay. RESULTS: Typical cage-like structures of submicroparticle with a diameter of about 40nm were observed by electron microscopy. Results from Bradford assay showed that the level of peptide incorporation was about 0.33g.L(-1). At the paralleled position close to the sixth band of the molecular weight marker(3480kDa) a clear band was shown in SDS-PAGE analysis, indicating successful incorporation of polypeptide into ISCOMS. It is suggested that ISCOMS delivery system could efficiently improve the immunogenicity of polypeptide and elicit specific immune responses in vivo by the results of ELISPOT assay, which showed that IFN-gamma producing cells(specific CTL responses) were increased(spots of ISCOMS-treated group: 47+/-5, n =3; control group: 5+/-2, n =3). CONCLUSION: ISCOMS-based hepatitis B polypeptide vaccine is successfully constructed and it induces a higher CTL response compared with short polypeptides vaccine in vivo.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
Recent studies have demonstrated that the membrane-proximal external region (MPER) of human immunodeficiency virus 1 (HIV-1) glycoprotein 41 contains a series of epitopes for human monoclonal antibodies, including...Recent studies have demonstrated that the membrane-proximal external region (MPER) of human immunodeficiency virus 1 (HIV-1) glycoprotein 41 contains a series of epitopes for human monoclonal antibodies, including 2F5, Zl3el, 4El0, and 10E8, which were isolated from HIV-l-infected individuals and show broad neutralizing activities. This suggests that MPER is a good target for the development of effective HIV-1 vaccines. However, many studies have shown that it is difficult to induce antibodies with similar broad neutralizing activities using MPER-based peptide antigens. Here, we report that 10E8-1ike neu- tralizing antibodies with effective anti-HIV-1 activity were readily induced using a precisely designed conformational immu- nogenic peptide containing the 10E8-specific epitope. This immunogenic peptide (designated T10HE) contains a 15-mer MPER-derived 10E8-specific epitope fused to T-helper-cell epitopes from tetanus toxin (tt), which showed a significantly sta- bilized a-helix structure after a series of modifications, including substitution with an (S)-c^-(2'-pentenyl) alanine containing an olefin-bearing tether and ruthenium-catalyzed olefin metathesis, compared with the unmodified T10E peptide. The stabilized (x-helix structure of T10HE did not affect its capacity to bind the 10E8 antibody, as evaluated with an enzyme linked immuno- sorbent assay (ELISA) and surface plasmon resonance binding assay (SPR assay). The efficacies of the T10HE and T10E epitope vaccines were evaluated after a standard vaccination procedure in which the experimental mice were primed with ei- ther the T10HE or T10E immunogen and boosted with HIV-1 JRFL pseudoviruses. Higher titers of 10E8-1ike antibodies were induced by T10HE than that by T10E. More importantly, the antibodies induced by T10HE showed enhanced antiviral potency against HIV-1 strains with both X4 and R5 tropism and a greater degree of broad neutralizing activity than the antibodies in- duced by T10E. These results indicate that a 10E8-epitope-based structure-specific peptide immunogen can elicit neutralizing antibodies when used as a vaccine prime.展开更多
We formulate an age-structured model based on a system of nonlinear partial differen- tial equations to assist the early and catch up female vaccination programs for human papillomavirus (HPV) types 6 and 11. Since ...We formulate an age-structured model based on a system of nonlinear partial differen- tial equations to assist the early and catch up female vaccination programs for human papillomavirus (HPV) types 6 and 11. Since these HPV types do not induce permanent immunity, the model, which stratifies the population based on age and gender, has a susceptible-infectious-susceptible (SIS) structure. We calculate the effective reproduction number Rv for the model and describe the local-asymptotic stability of the disease-free equilibrium using Rv. We prove the existence of an endemic equilibrium for Rv 〉 1 for the no vaccine case. However, analysis of the model for the vaccine case reveals that it undergoes the phenomenon of backward bifurcation. To support our theoretical results, we estimate the age and time solution with the given data for Toronto population, when an early and catch up female vaccine program is adopted, and when there is no vaccine. We show that early and catch up female vaccine program eliminates the infection in both male and female populations over a period of 30 years. Finally, we introduce the optimal control to an age-dependent model based on ordinary differential equations and solve it numerically to obtain the most cost-effective method for introducing the catch up vaccine into the population.展开更多
基金the National Natural Science Foundation of China,No.39789010
文摘AIM: To characterize the biochemical and immunological properties of an experimental ISCOMS vaccine prepared from a novel therapeutic polypeptide based on T cell epitopes of HBsAg, and a heptatis B-ISCOMS was prepared and investigated. METHODS: An immunostimulating complexes(ISCOMS)-based vaccine containing a novel therapeutic hepatitis B polypeptide was prepared by dialysis method, and its formation was visualized by electron microscopy and biochemically verified by SDS-polyacrylamide gel electrophoresis. Amount of the peptide within ISCOMS was determined by Bradford assay, and specific CTL response was detected by ELISPOT assay. RESULTS: Typical cage-like structures of submicroparticle with a diameter of about 40nm were observed by electron microscopy. Results from Bradford assay showed that the level of peptide incorporation was about 0.33g.L(-1). At the paralleled position close to the sixth band of the molecular weight marker(3480kDa) a clear band was shown in SDS-PAGE analysis, indicating successful incorporation of polypeptide into ISCOMS. It is suggested that ISCOMS delivery system could efficiently improve the immunogenicity of polypeptide and elicit specific immune responses in vivo by the results of ELISPOT assay, which showed that IFN-gamma producing cells(specific CTL responses) were increased(spots of ISCOMS-treated group: 47+/-5, n =3; control group: 5+/-2, n =3). CONCLUSION: ISCOMS-based hepatitis B polypeptide vaccine is successfully constructed and it induces a higher CTL response compared with short polypeptides vaccine in vivo.
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.
基金supported by Ministry of Science and Technology of China(2012ZX10001-009)
文摘Recent studies have demonstrated that the membrane-proximal external region (MPER) of human immunodeficiency virus 1 (HIV-1) glycoprotein 41 contains a series of epitopes for human monoclonal antibodies, including 2F5, Zl3el, 4El0, and 10E8, which were isolated from HIV-l-infected individuals and show broad neutralizing activities. This suggests that MPER is a good target for the development of effective HIV-1 vaccines. However, many studies have shown that it is difficult to induce antibodies with similar broad neutralizing activities using MPER-based peptide antigens. Here, we report that 10E8-1ike neu- tralizing antibodies with effective anti-HIV-1 activity were readily induced using a precisely designed conformational immu- nogenic peptide containing the 10E8-specific epitope. This immunogenic peptide (designated T10HE) contains a 15-mer MPER-derived 10E8-specific epitope fused to T-helper-cell epitopes from tetanus toxin (tt), which showed a significantly sta- bilized a-helix structure after a series of modifications, including substitution with an (S)-c^-(2'-pentenyl) alanine containing an olefin-bearing tether and ruthenium-catalyzed olefin metathesis, compared with the unmodified T10E peptide. The stabilized (x-helix structure of T10HE did not affect its capacity to bind the 10E8 antibody, as evaluated with an enzyme linked immuno- sorbent assay (ELISA) and surface plasmon resonance binding assay (SPR assay). The efficacies of the T10HE and T10E epitope vaccines were evaluated after a standard vaccination procedure in which the experimental mice were primed with ei- ther the T10HE or T10E immunogen and boosted with HIV-1 JRFL pseudoviruses. Higher titers of 10E8-1ike antibodies were induced by T10HE than that by T10E. More importantly, the antibodies induced by T10HE showed enhanced antiviral potency against HIV-1 strains with both X4 and R5 tropism and a greater degree of broad neutralizing activity than the antibodies in- duced by T10E. These results indicate that a 10E8-epitope-based structure-specific peptide immunogen can elicit neutralizing antibodies when used as a vaccine prime.
文摘We formulate an age-structured model based on a system of nonlinear partial differen- tial equations to assist the early and catch up female vaccination programs for human papillomavirus (HPV) types 6 and 11. Since these HPV types do not induce permanent immunity, the model, which stratifies the population based on age and gender, has a susceptible-infectious-susceptible (SIS) structure. We calculate the effective reproduction number Rv for the model and describe the local-asymptotic stability of the disease-free equilibrium using Rv. We prove the existence of an endemic equilibrium for Rv 〉 1 for the no vaccine case. However, analysis of the model for the vaccine case reveals that it undergoes the phenomenon of backward bifurcation. To support our theoretical results, we estimate the age and time solution with the given data for Toronto population, when an early and catch up female vaccine program is adopted, and when there is no vaccine. We show that early and catch up female vaccine program eliminates the infection in both male and female populations over a period of 30 years. Finally, we introduce the optimal control to an age-dependent model based on ordinary differential equations and solve it numerically to obtain the most cost-effective method for introducing the catch up vaccine into the population.