A Whole Recombinant Yeast-Based Therapeutic Vaccine Elicits HBV X, S and Core Specific T Cells in Mice and Activates Human T Cells Recognizing Epitopes Linked to Viral Clearance
Figure 8
GS-4774-emergent IFNγ responses in healthy subjects or CHB patients on adefovir therapy.
(A) TPDCs were used to stimulate autologous PBMCs (two rounds), followed by IFNγ ELISpot assay in the presence of HBV peptide pools. n = 5 subjects/group. P values (healthy vs. CHB): GS-4774, <0.0001; S-Core, 0.44; Yvec, 0.95 (B) IFNγ ELISpot response of TPDC-expanded T cells in a chronic HBV donor. P values, S-Core vs. Ovax: TPDC, 0.00051; TPDC plus rS&C, 0.0051. (C) Both CD4+ and CD8+ T cells from the CHB donor produce IFNγ in response to TPDC stimulation. P values, S-Core vs. Ovax: CD4, 0.0001; CD8, 0.0001. X-axis label abbreviations: TPDC, expansion with TPDCs only; TPDC plus rHBsAg or HBV peptides, expansion with TPDC followed by 24 hour incubation with rHBsAg or HBV peptides during the ELISpot or ICS assay. X-S-Core, fusion protein expressed in GS-4774.