title: Stimulation of immune systems by conjugated polymers and their potential as an alternative vaccine adjuvant.
abstract: Recently, conjugated polymers have been widely explored in the field of nanomedicine. Careful evaluations of their biological effects are thus urgently needed. Hereby, we systematically evaluated the biological effects of different types of conjugated polymers on macrophages and dendritic cells (DCs), which play critical roles in the innate and adaptive immune systems, respectively. While naked poly-(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (
  PSS) exhibits a high level of cytotoxicity, polyethylene glycol (PEG) modified
  PSS (PEDOT:PSS-PEG) shows greatly reduced toxicity to various types of cells. To our surprise, PEGylation of
  PSS could obviously enhance the cellular uptake of these nanoparticles, leading to subsequent immune stimulations of both macrophages and DCs. In contrast, another type of conjugated polymer, polypyrrole (PPy), is found to be an inert material with neither significant cytotoxicity nor noticeable immune-stimulation activity. Interestingly, utilizing ovalbumin (OVA) as a model antigen, it is further uncovered in our ex vivo experiment that
  PSS-PEG may serve as an adjuvant to greatly enhance the immunogenicity of OVA upon simple mixing. Our study on the one hand suggests the promise of developing novel nano-adjuvants based on conjugated polymers, and on the other hand highlights the importance of careful evaluations of the impacts of any new nanomaterials developed for nanomedicine on the immune systems.
authors.affiliation: Institute of Functional Nano & Soft Materials (FUNSOM), Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123, China. lgxu@suda.edu.cn rpeng@suda.edu.cn zliu@suda.edu.cn.
authors.forename: Hua
authors.initials: H
authors.lastname: Gong
authors.forename: Jian
authors.initials: J
authors.lastname: Xiang
authors.forename: Ligeng
authors.initials: L
authors.lastname: Xu
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Song
authors.forename: Ziliang
authors.initials: Z
authors.lastname: Dong
authors.forename: Rui
authors.initials: R
authors.lastname: Peng
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D008264:Macrophages / Q000166:cytology / Q000276:immunology*; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology; D013451:Sulfonic Acids / Q000737:chemistry / Q000494:pharmacology
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D011108:Polymers; D013451:Sulfonic Acids; C121383:poly(3,4-ethylene dioxythiophene); D011092:Polyethylene Glycols; C000595209:polyethylene glycol 1000; C077114:styrenesulfonic acid polymer