Antigen Presentation Ability of Salmonella Carrying DNA Vaccine Model and MCP-3 gene

The objective of this study is to determine the antigen presentation ability of a DNA vaccine model that is co-delivered with that of recombinant Salmonella enterica serovar Typhimurium (STM1) expressing chemokine macrophage chemotactic protein-3 (MCP-3). The DNA vaccine, pVROVA, was constructed by amplification of the ovalbumin coding region from sOVA-C1. Dendritic cells (DCs) were obtained from IL-4 and GMCSF stimulated mouse bone marrow stem cell. Cultured DCs were incubated with STM1 carrying a model ovalbumin gene (pVROVA). Furthermore, MHC class I antigen presentation of a dominant OVA peptide was assayed in vitro. The experiments were designed to determine the effect of co-delivering MCP-3 with that of ovalbumin in STM1. Our results show that a plasmid pROVA-carrying ovalbumin gene was succesfully constructed and sequence analysis of the ovalbumin-coding revealed an identity match of 100% with that of the chicken ovalbumin DNA sequences from the GenBank database. We also found that the presence of the MCP-3 encoding plasmid in STM1 or E. coli DH1 could increase the recovery of both STM1 and E. coli DH1 over those that carry the empty plasmids. Antigen presentation assay also indicates that MCP-3 can positively influence the presentation of ovalbumin. Conclusion: the infection of DCs by STM1-carrying DNA vaccine and MCP-3 results in an increase of processing and presentation of ovalbumin in vitro. Keywords : DNA vaccine, MCP-3, APC, Salmonella, Dendritic cell

Proteomics and in silico approaches to extend understanding of the glutathione transferase superfamily of the tropical liver fluke Fasciola gigantica

Fasciolosis is an important foodborne, zoonotic disease of livestock and humans, with global annual health and economic losses estimated at several billion US$. Fasciola hepatica is the major species in temperate regions, while F. gigantica dominates in the tropics. In the absence of commercially available vaccines to control fasciolosis, increasing reports of resistance to current chemotherapeutic strategies and the spread of fasciolosis into new areas, new functional genomics approaches are being used to identify potential new drug targets and vaccine candidates. The glutathione transferase (GST) superfamily is both a candidate drug and vaccine target. This study reports the identification of a putatively novel Sigma class GST, present in a water-soluble cytosol extract from the tropical liver fluke F. gigantica. The GST was cloned and expressed as an enzymically active recombinant protein. This GST shares a greater identity with the human schistosomiasis GST vaccine currently at Phase II clinical trials than previously discovered F. gigantica GSTs, stimulating interest in its immuno-protective properties. In addition, in silico analysis of the GST superfamily of both F. gigantica and F. hepatica has revealed an additional Mu class GST, Omega class GSTs, and for the first time, a Zeta class member

Cured by DNA-genetic immunization in the therapeutic sector

Historically, immunization has been designed to prevent the onset of infectious disease, with vaccines acting as prophylactic agents. However, over the course of time immunization has evolved to include a therapeutic objective whereby individuals who have already contracted an infectious or neoplastic disease, and where traditional treatment options are limited, are vaccinated. With diseases such as HIV and tuberculosis the limited success of traditional chemotherapeutic and prophylactic approaches has resulted in the experimental advancement of therapeutic genetic immunization, where the host immune system is to be modulated to improve disease prognosis or ultimately, eradicate the infection. Furthermore, for cancer, a major non-infectious disease, similar experimental treatments are underway. Here we will explore how genetic immunization enables re-direction of the host immune system resulting in the development of effective immune responses

Construction and Immunogenicity Testing of Salmonella, STM1 Vaccine Vector Expressing HIV-1 Antigen

Objective of this study: to determine the ability of Salmonella enterica serovar Typhimurium STM1 as a delivery vehicle for the HIV p24 gene and HIV env gene. The STM1 delivery HIV-p24 vaccination was carried out in the form of a recombinant or a DNA vaccine whereas only a DNA vaccine was used for HIV env. Naked DNA vaccination was also tested and immune responses were evaluated following immunisation in mouse model. Results: vaccination cellular immune responses induced by recombinant p24 STM1 (STM1/pHly-p24) were greater than those elicited by the p24 DNA vaccine in STM1 (STM1/VR-p24), (but statistically not significance) than those induced by oral vaccination. However, IgA responses induced by oral vaccination with either a recombinant or DNA vaccine of p24 in STM1 are higher than those induced by IP vaccination. Conclusions: This result confirmsother studies that Salmonella was able to deliver HIV antigens to the immune system and induced specific immune responses to the HIV antigen

Construction and Immunogenicity Testing of Salmonella, STM1 Vaccine Vector Expressing HIV-1 Antigen

Objective of this study: to determine the ability of Salmonella enterica serovar Typhimurium STM1 as a delivery vehicle for the HIV p24 gene and HIV env gene. The STM1 delivery HIV-p24 vaccination was carried out in the form of a recombinant or a DNA vaccine whereas only a DNA vaccine was used for HIV env. Naked DNA vaccination was also tested and immune responses were evaluated following immunisation in mouse model. Results: vaccination cellular immune responses induced by recombinant p24 STM1 (STM1/pHly-p24) were greater than those elicited by the p24 DNA vaccine in STM1 (STM1/VR-p24), (but statistically not significance) than those induced by oral vaccination. However, IgA responses induced by oral vaccination with either a recombinant or DNA vaccine of p24 in STM1 are higher than those induced by IP vaccination. Conclusions: This result confirms</div><div>other studies that Salmonella was able to deliver HIV antigens to the immune system and induced specific immune responses to the HIV antigen

Antigen Presentation Ability of Salmonella Carrying DNA Vaccine Model and MCP-3 gene

The objective of this study is to determine the antigen presentation ability of a DNA vaccine model that is co-delivered with that of recombinant Salmonella enterica serovar Typhimurium (STM1) expressing chemokine macrophage chemotactic protein-3 (MCP-3). The DNA vaccine, pVROVA, was constructed by amplification of the ovalbumin coding region from sOVA-C1. Dendritic cells (DCs) were obtained from IL-4 and GMCSF stimulated mouse bone marrow stem cell. Cultured DCs were incubated with STM1 carrying a model ovalbumin gene (pVROVA). Furthermore, MHC class I antigen presentation of a dominant OVA peptide was assayed in vitro. The experiments were designed to determine the effect of co-delivering MCP-3 with that of ovalbumin in STM1. Our results show that a plasmid pROVA-carrying ovalbumin gene was succesfully constructed and sequence analysis of the ovalbumin-coding revealed an identity match of 100% with that of the chicken ovalbumin DNA sequences from the GenBank database. We also found that the presence of the MCP-3 encoding plasmid in STM1 or E. coli DH1 could increase the recovery of both STM1 and E. coli DH1 over those that carry the empty plasmids. Antigen presentation assay also indicates that MCP-3 can positively influence the presentation of ovalbumin. Conclusion: the infection of DCs by STM1-carrying DNA vaccine and MCP-3 results in an increase of processing and presentation of ovalbumin in vitro.Keywords : DNA vaccine, MCP-3, APC, Salmonella, Dendritic cell

The malaria war

The 25th of April is a national day to honour the members of the Australian and New Zealand Army Corps (ANZAC), who gave their lives at Gallipoli during the First World War (WWI). The 25th of April has also been designated World Malaria Day by the World Health Organization (WHO), and is commemorated every year to bring awareness of deaths caused by malaria infection and global efforts to control infection. There is no coincidence that these two commemorative events are on the same day, as military campaigns suffered great burdens caused by malaria infection during WWI. Malaria infection is yet to be eradicated from human history; fundamental discoveries of malaria and its control were developed during WWI and the fight against malaria continues to this date. This article focuses on the discovery of malaria prior to WWI, the impact that malaria had on military in the war, and the development of control measures taken to minimize these effects and to subsequently eradicate the disease in many countries

Influence of Promoter, Gene Copy Number, and Preexisting Immunity on Humoral and Cellular Responses to a Vectored Antigen Delivered by a Salmonella enterica Vaccine▿

Attenuated Salmonella strains are currently in production as vaccines for protection of animals against salmonellosis. Such commercial strains offer the potential to deliver heterologous antigen to protect animals against other diseases. One vaccine strain, attenuated Salmonella enterica serovar Typhimurium (STM-1), was tested for the ability to deliver ovalbumin and to induce immune responses in mice. Two vaccine trials were performed testing the influence of promoter choice, the location of the encoding DNA (plasmid or chromosome), and the effect of preexisting homologous or heterologous immunity. The results demonstrated that humoral and T-cell responses were induced from either of two promoters, from either the plasmid or the chromosome, and that preexposure to the empty homologous vector, STM-1, or the heterologous vector, S. enterica serovar Enteritidis, had no detrimental effect on subsequent antigen-specific responses. In the case of homologous preexposure, responses were generally greater, and this was correlated with an increased uptake of Salmonella by macrophages in vitro after opsonization with immune sera