T cell responses to Tarmogen-pulsed DCs in ENGERIX-B vaccinated donor samples.

<p>TPDCs were used to stimulate autologous PBMCs over 3 rounds to expand HBV-specific T cells. (A) IFNγ ELISpot response of a donor immunized with Engerix-B six months prior to TPDC expansion. S-Core Tarmogen: identical to GS-4774 except for the absence of HBxAg. <b><u>P values</u></b> (TPDC plus rHBsAg only): GS-4774 vs. Yvec, 0.0001; S-Core vs. Yvec, 0.0001. (B) ICS staining of donor cells collected 20 years post Engerix-B immunization to evaluate the LAMP1 phenotype of IFNγ-secreting CD4⁺ and CD8⁺ T cells. HBV peptides for CD4⁺ T cell response: PICPGYRWMCLRRFIIFL, FFLLTRILTIPQSLD, SGFLGPLLVLQAGFFLLTR, TRILTIPQSLDSWWTSLNF 10 µg/mL each. HBV peptides for CD8⁺ T cell responses: VLQAGFFLL, FLLTRILTI, LLDYQGMLPV, WLSLLVPFV, SIVSPFIPLL 10 µg/mL each. <b><u>P values</u></b> (TPDC plus HBV peptides), S-Core vs. Yvec: CD8, 0.0001; CD4, 0.0002.