ABSTRACT
In recent years, the development of new vaccines such as nucleic acid vaccines, genetically engineered vaccines, and synthetic peptide vaccines has achieved rapid development. However, compared with traditional inactivated or live vaccines, these vaccines often have problems such as poor immunogenicity. Therefore, an adjuvant is needed to enhance its effect, and adjuvants have proven to be a key component in vaccines. There are many types of adjuvants, while currently no unified standard for the classification. At present, the most commonly used adjuvants are Aluminum adjuvant and Freund's adjuvant, but new generation vaccines will probably need new generation adjuvants. Thus, this review aims to showcase the current status of immune adjuvants, with the focus on immunomodulatory molecular adjuvant, antigen delivery adjuvant and compound adjuvant. This review provides new insights for the development of novel vaccine adjuvants.