HTI responses are boosted by MVA.HTI vaccination. (A) Vaccination schedule of mice (n = 6/group) vaccinated with different prime/boost regimens including: 2xDNA (DD), 3xDNA (DDD), 4xDNA (DDDD); DNA prime followed by MVA boost (DDM and DDDM). 147 peptides (15-mers, overlapping by 11 residues) spanning the entire HTI sequence (including the leader sequence and linkers regions) were used in an IFN-γ ELISPOT assay to assess immunogenicity of the different regimens. Data from 1 animal in the DD group was not evaluated due to high background result in the ELISPOT assay. Breadth (B) and magnitude (C-E) of induced HTI-specific IFN-γ responses in different groups of mice to a set of 16 peptide pools spanning the different protein segments is shown either as total HTI-specific responses (C, D) or as response to individual proteins (E). Bars represent median values. Median with interquartile range is shown in panel E. Panel D is an independent mouse experiment conducted to compare responses after DDD, DDDD and DDDM vaccination.