Background and purpose: In recent years nanotechnology has a significant impact on various fields of human life, especially in pharmaceutical and medical needs. Some biopolymers such as chitosan which is also biocompatible are low cost and abundantly found, so, their application for vaccine production is cost benefit. Trimethyl chitosan is a deacetylated derivative of chitosan that could be used to increase the induction of immune response. In this study, trimethyl chitosan nanoparticles containing tetanus protein were used to stimulate the immune system.

Materials and methods: In this experimental study, synthesis of the tetanus toxoid loaded nanoparticles was done by ion gelation method. Physical features of the nanoparticles were investigated using scanning electron microscopy (SEM). The nanoparticles were then injected subcutaneously into mice. After the sampling process, the immune system stimulation was evaluated using indirect ELISA. Data was analyzed using one-way ANOVA and significance level of P< 0.05. 

Results: The purity of protein was confirmed by SDS-PAGE and encapsulated proteins were loaded up to 80 percent. ELISA results showed that the immune system was stimulated significantly compared with Freund adjuvant, and antibody titer increased.

Conclusion: Tetanus toxoid loaded Trimethyl chitosan nanoparticles increase the stimulation of immune system and are more effective in comparison with Freund's adjuvant.