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Aims: Riemerella anatipestifer infections of goslings and ducklings can result in high mortality. Since there are at least 21 serotypes of R. anatipestifer, crossprotection is an important goal for vaccine development. Methods and Results: In this study, we evaluated the immunostimulatory effect of different immunization regimens -- the traditional inactivated vaccine vs prime--boost regimens using DNA and protein subunit vaccines (DNA+subunit, subunit+subunit, subunit+inactivated and DNA+DNA). Results showed that, when compared to the inactivated vaccine, prime--boost regimens induced higher and up to 16-week longer lasting levels of antibody responses, significantly elevated the percentage of the cytotoxic CD8+ T cell and higher expression levels of IFN-c, IL-6 and IL-12 mRNAs. Furthermore, as an indication of cross-protection, sera from prime--boost regimens were able to recognize lysates of R. anatipestifer serotypes 1, 2 and 6. Conclusions: Prime--boost regimens especially DNA-prime and protein-boost, induce strong long-term immune response and may prove protective for breeder ducks requiring long-term protection. Significance and Impact of the Study: It is worth mentioning that the subunit+inactivated regimen group also elicited strong immune response. The cost of this regimen may only be half of the other prime--boost regimens, making this subunit + inactivated combination an attractive option. [ABSTRACT FROM AUTHOR]

Aims: To examine the modulation of the interacting partners of the calcineurin (CaN)‐NFAT pathway in T cells during Cryptococcus neoformans fungal infection and post‐T11TS immunotherapy. Methods and Results: Wistar rats were infected with C. neoformans and followed by immunotherapy with immune‐potentiator T11TS. T cells were analysed by flow cytometry, immunoblotting and nuclear translocation study. The signalling proteins LCK, FYN, LAT, PLCγ1 and CaN in T cells were regulated by C. neoformans infection resulting in reduced nuclear translocation of NFAT and IL‐2 expression. Following T11TS immunotherapy, the expressions of the above‐mentioned proteins were boosted and thus resulting in the clearance of C. neoformans from lung and spleen. Conclusions: The precise mechanism of suppression of the T‐cell function by C. neoformans is still unknown. Previously, we have shown that T11TS positively regulates the function of T cells to abrogate glioma and other immunosuppressive conditions. T11TS immunotherapy increased the expression of the above signalling partners of the CaN‐NFAT pathway in T cells and improved nuclear retention of NFAT. As a result, an increased IL‐2 expression leads to activation and proliferation of T cells. Significance and Impact of the Study: Our results demonstrate the role of T11TS in restoring the CaN‐NFAT signalling pathway in T cells. It identifies T11TS as an immunotherapeutic agent with potential clinical outcomes to counteract C. neoformans infection. [ABSTRACT FROM AUTHOR]