Hybrid nanoparticle-based nicotine nanovaccines: Boosting the immunological efficacy by conjugation of potent carrier proteins.

A series of hybrid nanoparticle-based nicotine nanovaccines (NanoNicVac) were engineered in this work by conjugating potent carrier protein candidates (Keyhole limpet hemocyanin (KLH) multimer, KLH subunit, cross-reactive material 197 (CRM), or tetanus toxoid (TT)) for enhanced immunological efficacy. NanoNicVac with CRM or TT were processed by dendritic cells more efficiently than that with KLH multimer or subunit. NanoNicVac carrying CRM or TT exhibited a significantly higher immunogenicity against nicotine and a considerably lower immunogenicity against carrier proteins than NanoNicVac carrying KLH multimer or subunit in mice. The in vivo results revealed that NanoNicVac with CRM or TT resulted in lower levels of nicotine in the brain of mice after nicotine challenge. All findings suggest that an enhanced immunological efficacy of NanoNicVac can be achieved by using CRM or TT instead of KLH or KLH subunit as carrier proteins, making NanoNicVac a promising next-generation immunotherapeutic candidate against nicotine addiction.