Applications of Chitosan Derivatives as Adjuvant for Nanoparticles Based Vaccines.

This review focuses on the applications of chitosan derivatives towards vaccine delivery for their role as adjuvants. Adjuvants have been used as one of the key components in modern-day vaccines to enhance the immune response or as a drug delivery carrier. Generally, vaccines are administered to protect the host against harmful disease-causing infectious pathogens. The area of vaccine delivery is reaching new heights day by day with the evolution of the strategies and tools used for vaccine development. Currently, the vaccines have created a great impact by saving the lives of many human beings. A narrative review of all the relevant papers were conducted across the databases of PubMed and ScienceDirect. Based on the various studies performed in various animal models, the chitosan nanoparticle (CNP) was reported to be a safe and effective adjuvant candidate for a wide range of prophylactic and therapeutic vaccines that require a balanced and potent stimulation of both the cellular and humoral responses, due to its natural origin and good biocompatibility, as well as its lack of lethal toxicity to humans and animals. There was a tremendous shift in the paradigm of vaccine drug delivery from the use of conventional to novel adjuvants. For the development of a promising vaccine delivery system, adjuvant plays an irreplaceable role, but the adjuvants have not been utilized to their full potential because of the limited number of approved adjuvants. Hence the search for novel adjuvants is highly increased. In the list of versatile adjuvants, chitosan derivatives occupy an important place because of their huge benefits. The chitosan derivatives are obtained by the chemical modification of chitosan. The studies performed on various animal models validate the potential use of chitosan dervatives as adjuvants for vaccine delivery.