Fig. 4

T7-EA increases HBsAg-specific Th1 immune responses in CD4⁺ T cell dependent manner. a, b Groups of Balb/c mice (n = 5 per group) were immunized intraperitoneally with 2 μg HBsAg mixed with 100 nmol T7, T7-EA or R848 at day 0, 14 and 28. HBsAg specific IgG1 and IgG2a were measured by ELISA in serum obtained 7 days after the third immunization. c, d Splenocytes were isolated 7 days after the third immunization, and HBsAg-specific T cells were detected by Elispot assay. The cells were cultured at a density of 3 × 10⁵ cells/well with 20 μg/mL HBsAg in a 96 well pre-coated Elispot plate for 18 h. e, f Groups of Balb/c mice (n = 4 per group) were immunized intraperitoneally with 2 μg HBsAg mixed with 100 nmol T7-EA and Alum adjuvant at day 0. CD4⁺ or Ly6c⁺ cells were depleted by antibody treatment. Splenocytes were isolated 7 days after the immunization. Elispot assay was used for HBsAg-specific T-cell detection. The cells were cultured at a density of 3×10⁵ cells/well with 20 μg/mL HBsAg in the 96 well pre-coated Elispot plate for 18 h. A student’s t test was used for data analysis. The data represent the mean ± SD. * P < 0.05