Annual vaccination is necessary to maintain humoral immunity in the elderly population. However, the factors influencing the response to influenza vaccination have not been completely identified. The aim of this study...Annual vaccination is necessary to maintain humoral immunity in the elderly population. However, the factors influencing the response to influenza vaccination have not been completely identified. The aim of this study was to explore the factors that influenced antibody responses to repeated vaccination using measures that were both objective and quantitative. A total of 111 volunteers aged > 61 years were vaccinated subcutaneously with one dose of influenza vaccine from the 2005-2006 season through the 2009-2010 season. The factors that influenced antibody responses after vaccination were evaluated. The seroprotection rates (PRs) were significantly higher in responders (subjects with a higher antibody titer in the 2005-2006 season) than in nonresponders only in the 2006-2007 and 2007-2008 seasons. PRs after vaccination were significantly higher in seropositive individuals (subjects with a higher prevaccination antibody titer in the 2006-2007 season) than in seronegative individuals for all three virus strains in almost all of the 5 years. Age, gender, and vaccination in the 2004-2005 season did not influence the response. These results suggest that an immune response at a certain time point would predict immune responses only in the near future. However, prevaccination antibody titer in the following season is the ideal predictor for future responses that last over several influenza seasons.展开更多
Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of straintranscending malarial vaccines.The present study sought to determine safety,immunogenicity and cross-species e...Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of straintranscending malarial vaccines.The present study sought to determine safety,immunogenicity and cross-species efficacy of Plasmodium falciparum serine repeat antigen 5 polypeptide co-expressed with epitopes of BacilleCalmette Guerin(BCG),tetanus toxoid(TT) and a chemokine gene.Olive baboons and BALB/c mice were randomly assigned into vaccine and control groups.The vaccine group animals were primed and boosted twice with pIRES plasmids encoding the SERA5 + BCG + TT alone,or with either CCL5 or CCL20 and the control group with pIRES plasmid vector backbone.Mice and baboons were challenged with P.berghei ANKA and P.knowlesi H strain parasites,respectively.Safety was determined by observing for injection sites reactogenicities,hematology and clinical chemistry.Parasitaemia and survivorship profiles were used to determine cross-species efficacy,and T cell phenotypes,Th1-,Th2-type,T-regulatory immune responses and antibody responses were assessed to determine vaccine immunogenicity.The pSeBCGTT plasmid DNA vaccines were safe and induced Thl-,Th2-type,and Tregulatory responses vaccinated animals showed enhanced CD4~+(P〈0.01),CD 8~+ T cells(P〈 0.001) activation and IgG anti-SE36 antibodies responses(P〈 0.001) at week 4 and 8 post vaccination compared to the control group.Vaccinated mice had a 31.45-68.69%cumulative parasite load reduction and 60%suppression in baboons(P〈0.05)and enhanced survivorship(P〈 0.001) with no clinical signs of malaria compared to the control group.The results showed that the vaccines were safe,immunogenic and conferred partial cross-species protection.展开更多
文摘Annual vaccination is necessary to maintain humoral immunity in the elderly population. However, the factors influencing the response to influenza vaccination have not been completely identified. The aim of this study was to explore the factors that influenced antibody responses to repeated vaccination using measures that were both objective and quantitative. A total of 111 volunteers aged > 61 years were vaccinated subcutaneously with one dose of influenza vaccine from the 2005-2006 season through the 2009-2010 season. The factors that influenced antibody responses after vaccination were evaluated. The seroprotection rates (PRs) were significantly higher in responders (subjects with a higher antibody titer in the 2005-2006 season) than in nonresponders only in the 2006-2007 and 2007-2008 seasons. PRs after vaccination were significantly higher in seropositive individuals (subjects with a higher prevaccination antibody titer in the 2006-2007 season) than in seronegative individuals for all three virus strains in almost all of the 5 years. Age, gender, and vaccination in the 2004-2005 season did not influence the response. These results suggest that an immune response at a certain time point would predict immune responses only in the near future. However, prevaccination antibody titer in the following season is the ideal predictor for future responses that last over several influenza seasons.
基金Gene Art for engineering the vaccine constructs and the Uganda Council of Science and Technology (UCST)/World Bank for providing the funds for the work
文摘Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of straintranscending malarial vaccines.The present study sought to determine safety,immunogenicity and cross-species efficacy of Plasmodium falciparum serine repeat antigen 5 polypeptide co-expressed with epitopes of BacilleCalmette Guerin(BCG),tetanus toxoid(TT) and a chemokine gene.Olive baboons and BALB/c mice were randomly assigned into vaccine and control groups.The vaccine group animals were primed and boosted twice with pIRES plasmids encoding the SERA5 + BCG + TT alone,or with either CCL5 or CCL20 and the control group with pIRES plasmid vector backbone.Mice and baboons were challenged with P.berghei ANKA and P.knowlesi H strain parasites,respectively.Safety was determined by observing for injection sites reactogenicities,hematology and clinical chemistry.Parasitaemia and survivorship profiles were used to determine cross-species efficacy,and T cell phenotypes,Th1-,Th2-type,T-regulatory immune responses and antibody responses were assessed to determine vaccine immunogenicity.The pSeBCGTT plasmid DNA vaccines were safe and induced Thl-,Th2-type,and Tregulatory responses vaccinated animals showed enhanced CD4~+(P〈0.01),CD 8~+ T cells(P〈 0.001) activation and IgG anti-SE36 antibodies responses(P〈 0.001) at week 4 and 8 post vaccination compared to the control group.Vaccinated mice had a 31.45-68.69%cumulative parasite load reduction and 60%suppression in baboons(P〈0.05)and enhanced survivorship(P〈 0.001) with no clinical signs of malaria compared to the control group.The results showed that the vaccines were safe,immunogenic and conferred partial cross-species protection.