Co-delivery of antigens and immunostimulants a polymersome for improvement of antigen-specific immune response

• Published in: Journal of materials chemistry. B, Materials for biology and medicine Materials for biology and medicine, 2020-07, Vol.8 (26), p.562-5626
• Main Authors: Lim, Jong-Woo, Na, Woonsung, Kim, Hyun-Ouk, Yeom, Minjoo, Kang, Aram, Park, Geunseon, Park, Chaewon, Ki, Jisun, Lee, Sojeong, Jung, Bud, Jeong, Hyoung Hwa, Park, Daewon, Song, Daesub, Haam, Seungjoo
• Format: Article
• Language: English
• ISSN: 2050-750X; 2050-7518
• DOI: 10.1039/d0tb00892c

Cellular uptake of antigens (Ags) by antigen-presenting cells (APCs) is vital for effective functioning of the immune system. Intramuscular or subcutaneous administration of vaccine Ags alone is not sufficient to elicit optimal immune responses. Thus, adjuvants are required to induce strong immunogenicity. Here, we developed nanoparticulate adjuvants that assemble into a bilayer spherical polymersome (PSome) to promote the cellular uptake of Ags by APCs. PSomes were synthesized by using a biodegradable and biocompatible block copolymer methoxy-poly(ethylene glycol)- b -poly( d , l -lactide) to encapsulate both hydrophilic and lipophilic biomacromolecules, such as ovalbumin (OVA) as a model Ag and monophosphoryl lipid A (MPLA) as an immunostimulant. After co-encapsulation of OVA and MPLA, the PSome synthetic vehicle exhibited the sustained release of OVA in cell environments and allowed efficient delivery of cargos into APCs. The administration of PSomes loaded with OVA and MPLA induced the production of interleukin-6 and tumor necrosis factor-alpha cytokines by macrophage activation in vitro and elicited effective Ag-specific antibody responses in vivo . These findings indicate that the nano-sized PSome may serve as a potent adjuvant for vaccine delivery systems to modulate enhanced immune responses. Bilayer spherical polymersome based adjuvants promote the antigen cellular uptake into antigen-presenting cells. The administration of polymersome loading OVA and MPLA induce the secretion of cytokines by macrophage activation and elicit potent antigen-specific antibody responses.