Figure 4.

Humoral immune responses by exosomes were analyzed. Mice were immunized three times with either PBS, Exo 5 µg or Exo 20 µg or CIITA-Exo 5 µg or CIITA-Exo 20 µg. The experiments were repeated twice and displayed similar results. Sera from the immunized mice were obtained and were pooled one week after each immunization (1^st, 2^nd and 3^rd week). (A) Anti-mouse IgG and IgM antibody was used to detect whole antibodies. (B) Anti-IgG1- and anti-IgG2a-speicific antibodies were used to detect antibody isotypes. Statistical significance; ns: not significant, ^*: P <0.05, ^**: P <0.01.