IsdB has significant vaccine activity when administered to mice, and IsdB specific antibodies generated by active immunization can confer protection.,, In light of the expanding evidence supporting the importance of T cells in immunity to bacteria, we initiated experiments to explore the role of lymphocytes in IsdB mediated protection.
Expression of gp100 and SPD-CD40L as separate molecules did not enhance survival, highlighting the requirement to encode gp100 within SPD-CD40L for optimal vaccine activity.
Furthermore, the ATP-binding domain deletion mutant Hsp70382 641, when fused to E7, was immunologically effective, suggesting that the peptide-binding region, not the ATPase domain of Hsp70, is required for the vaccine activity of the E7-Hsp70 DNA.
As such, measurement of total levels of antigen-specific antibody is not an appropriate measure of vaccine activity since not all antibodies would be able to provide therapeutic effect.
Our previous experience with A/Indonesia/5/2005 H5N1 strain has shown that cross-reactivity is stronger when assessed by the more sensitive neutralisation assay [23] which provides an evaluation of the vaccine activity against both the HA and the NA antigens and consequently, gives a more comprehensive evaluation of the biological activity of the vaccine.
Thus, many different strategies can be utilized to improve the genetic vaccine activity.
In animal models for studying tumour vaccines, temsirolimus enhanced vaccine activity by enhancing effector T-cell function and enhancing the production of CD8 memory T cells.
- The idea is that antigen presentation in the absence of costimulatory molecules and without a complement of proinflammatory cytokines is critical for inhibitory vaccine activity.
In initial studies of the safety and immunogenicity of these vaccines, volunteers should have low anti-CP antibody titers to preclude pre-existing antibody interference with the analysis of vaccine activity.
