Acetalated dextran microparticles are a potent delivery platform for vaccine adjuvants in vitro

摘要

In an effort to produce a more potent protein based vaccine, TLR 7 agonist imiquimod was encapsulated in microparticles made of the novel biomaterial, acetalated dextran (Ac-DEX). Ac-DEX is a pH sensitive biopolymer that degrades via the pH change present during antigen presenting cell (APC) phagocytosis. In vitro cytokine production and RT-PCR concludes that several inflammatory cytokines are upregulated in APCs cultured with imiquimod loaded Ac-DEX particles (MH-S and RAW 264.7 macrophages and bone marrow derived dendritic cells (BMDCs)). Dose sparing is observed, in that significantly less imiquimod is required for equivalent cell activation, compared to free imiquimod. Dose sparing, coupled with the passive targeting of APCs afforded with nanoparticle encapsulation, indicate that Ac-DEX encapsulated of imiquimod could increase protein vaccine efficacy.