Fast antibody responses by immuno-targeting and nanotechnology strategies versus HBsAg vaccine

Though immunization with HBsAg has been routine since the 1980s, it has numerous limitations such as low or none humoral immune responses. Today, nanotechnology is used in vaccinology to achieve higher potency. The present study deals with the achievement of fast antibody response of humoral immune responses using immune-targeting through mannosylated nanocarriers of the vaccine.

Mannose sugar and HBsAg were attached to the surface of iron oxide nanoparticles. Mannosylated iron oxide nanoparticles conjugated HBsAg (HBsAg +MLCMNP), iron oxide nanoparticles conjugated HBsAg (HBsAg +LCMNP), hepatitis B vaccine, and mere HBsAg were injected twice to BALB/c mice subcutaneously, while suitable control groups were considered. Specific total IgG antibodies were evaluated on the 7th and 14th days after the final immunization. The avidity maturation of the humoral immune response was assessed with an optimized ELISA. Graph pad prism software was used to analyze statistical data.

Results showed that on the seventh day of the final shooting, the mannosylated nano-vaccine caused higher antibody response induction than nano-vaccine without mannose and commercial vaccine groups. After 14 days of the second injection, a significant difference was seen versus the nano-vaccine without mannose but not the commercial vaccine group. In addition, the avidity index in mannosylated nano-vaccine showed a significant increase compared with the nano-vaccine without mannose and mere HBsAg group but not compared with the commercial vaccine.

It seems that mannosylated nano-vaccine has more potency to achieve fast antibody responses and also higher quality of humoral immune response.