Conclusion
Therefore, these results suggest that CS/O-HTCC nanoparticles are ideal vaccine adjuvants for soluble antigens used in intranasal or mucosal vaccination.
Methods
By using the advantages of polysaccharides, which can promote both T-helper 1 and 2 responses, curdlan sulfate (CS)-O-(2-hydroxyl)propyl-3-trimethyl ammonium chitosan chloride (O-HTCC) nanoparticles were prepared by interacting CS with O-HTCC, and the adjuvancy of the nanoparticles was investigated.
Results
The results showed that the polysaccharide-based nanoparticles induced the proliferation and activation of antigen-presenting cells. High protein-loading efficiency was obtained by testing with the model antigen ovalbumin (Ova), and the Ova adsorbed onto the cationic CS/O-HTCC complexes was taken up easily by the epithelium. To evaluate the capacity of the Ova/CS/O-HTCC nanoparticles for immune enhancement in vivo, we collected and analyzed immunocytes, serum, and mucosal lavage fluid from intranasally vaccinated mice. The results showed that Ova/CS/O-HTCC nanoparticles induced activation and maturation of antigen-presenting cells and provoked the proliferation and differentiation of lymphocytes more significantly compared to the immunization of Ova mixed with aluminum hydroxide gel. Furthermore, CS/O-HTCC evoked a significantly higher level of Ova-specific antibodies.