Abstract
Foot-and-mouth disease (FMD) is a highly contagious and economically devastating disease of cloven-hoofed animals with an almost-worldwide distribution. Conventional FMD vaccines consisting of chemically inactivated viruses have aided in the eradication of FMD from Europe and remain the main tool for control in endemic countries. Although significant steps have been made to improve the quality of vaccines, such as improved methods of antigen concentration and purification, manufacturing processes are technically demanding and expensive. Consequently, there is large variation in the quality of vaccines distributed in FMD-endemic countries compared with those manufactured for emergency use in FMD-free countries. Here, we have used reverse genetics to introduce haemagglutinin (HA) and FLAG tags into the foot-and-mouth disease virus (FMDV) capsid. HA- and FLAG-tagged FMDVs were infectious, with a plaque morphology similar to the non-tagged parental infectious copy virus and the field virus. The tagged viruses utilized integrin-mediated cell entry and retained the tag epitopes over serial passages. In addition, infectious HA- and FLAG-tagged FMDVs were readily purified from small-scale cultures using commercial antibodies. Tagged FMDV offers a feasible alternative to the current methods of vaccine concentration and purification, a potential to develop FMD vaccine conjugates and a unique tool for FMDV research.
Highlights
The CD4+ T cell response to FMDV vaccination has been examined using established methods. Antigen‐specific cell proliferation was used to assess the functional capacity of cell populations using either whole PBMC or purified cell populations (CD4+ cells) Carboxyfluorescein diacetate succinimydyl ester (CFSE) labelling was used as a marker for cell division in in vitro assays
We have carried out methods to quantitate IFN‐γ in cell supernatants (ELISA) and identify cell subsets involved in its production by intracellular flow cytometry
By combining surface antigen and CFSE staining, we showed each T cell subset examined exhibited some degree of cell division/proliferation following culture in vitro with either vaccine antigen or peptide (Fig 3)
Summary
The CD4+ T cell response to FMDV vaccination has been examined using established methods. Carboxyfluorescein diacetate succinimydyl ester (CFSE) labelling was used as a marker for cell division in in vitro assays. The dye‐protein passively diffuses into cells and is retained by the cells until meiosis and fluorescent intensity is subsequently reduced by 50% with each cell division. Interferon‐gamma (IFN‐γ) is regarded as a key immuno‐regulator. We have carried out methods to quantitate IFN‐γ in cell supernatants (ELISA) and identify cell subsets involved in its production by intracellular flow cytometry. Parallel analyses such as this should provide us with a better understanding of the CD4+ T cell responses post‐vaccination
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
