LAUSR

Adjuvants have been widely used in vaccine to improve the protection or treatment efficacy. However, so far they inevitably produce side effects and are hard to induce cellular immunity in practical application. Here, we fabricated two kinds of amphiphilic poly(glutamic acid) nanoparticales (α-PGA-F and γ-PGA-F NPs) as nanocarrier adjuvants to induce an effective cellular immune response. Amphiphilic PGA were synthesized by grafting phenylalanine ethyl ester to form biodegradable self-assembly nanoadjuvants in a water solution. The model antigen, chicken ovalbumin (OVA), could be loaded into PGA-F NPs (OVA@PGA-F NPs) with the high loading ratio above 12%. Moreover, compared with γ-PGA-F NPs, the acidic environment could induce the α-helical secondary structure of α-PGA NPs, promoting membrane fusion and more fast antigen lysosomal escape. Hence, the antigen presenting cells treated with OVA@α-PGA-F NPs showed higher secretion of inflammatory cytokines, and higher expression of major biological histocompatibility complex class I and CD80 than those of OVA@γ-PGA-F NPs. Overall, this work indicated that pH responsive α-PGA-F NPs as a carrier adjuvant can effectively improve the ability of cellular immune responses, leading to it being a potent candidate for vaccine applications. This article is protected by copyright. All rights reserved.