Dataset Information

PH-degradable imidazoquinoline-ligated nanogels for lymph node-focused immune activation.

ABSTRACT: Agonists of Toll-like receptors (TLRs) are potent activators of the innate immune system and hold promise as vaccine adjuvant and for anticancer immunotherapy. Unfortunately, in soluble form they readily enter systemic circulation and cause systemic inflammatory toxicity. Here we demonstrate that by covalent ligation of a small-molecule imidazoquinoline-based TLR7/8 agonist to 50-nm-sized degradable polymeric nanogels the potency of the agonist to activate TLR7/8 in in vitro cultured dendritic cells is largely retained. Importantly, imidazoquinoline-ligated nanogels focused the in vivo immune activation on the draining lymph nodes while dramatically reducing systemic inflammation. Mechanistic studies revealed a prevalent passive diffusion of the nanogels to the draining lymph node. Moreover, immunization studies in mice have shown that relative to soluble TLR7/8 agonist, imidazoquinoline-ligated nanogels induce superior antibody and T-cell responses against a tuberculosis antigen. This approach opens possibilities to enhance the therapeutic benefit of small-molecule TLR agonist for a variety of applications.

SUBMITTER: Nuhn L

PROVIDER: S-EPMC4961133 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

pH-degradable imidazoquinoline-ligated nanogels for lymph node-focused immune activation.

Nuhn Lutz L Vanparijs Nane N De Beuckelaer Ans A Lybaert Lien L Verstraete Glenn G Deswarte Kim K Lienenklaus Stefan S Shukla Nikunj M NM Salyer Alex C D AC Lambrecht Bart N BN Grooten Johan J David Sunil A SA De Koker Stefaan S De Geest Bruno G BG

Proceedings of the National Academy of Sciences of the United States of America 20160705 29

Agonists of Toll-like receptors (TLRs) are potent activators of the innate immune system and hold promise as vaccine adjuvant and for anticancer immunotherapy. Unfortunately, in soluble form they readily enter systemic circulation and cause systemic inflammatory toxicity. Here we demonstrate that by covalent ligation of a small-molecule imidazoquinoline-based TLR7/8 agonist to 50-nm-sized degradable polymeric nanogels the potency of the agonist to activate TLR7/8 in in vitro cultured dendritic c ...[more]

PMID: 27382168

Similar Datasets

Project description:Liver fibrosis is a hard-to-treat disease with liver transplantation as only effective curation to this date. During disease progression, immune suppressive macrophages dominate and support fibrosis formation by replacement of functional parenchyma with collagen-dominating scare tissue. To alter the macrophage behavior, a pH-degradable, nanogel-based delivery system was developed for the covalent conjugation of the clinically approved bisphosphonate alendronate. The nanocarrier mediates the drugs’ delivery into hepatic nonparenchymal cells after intravenous administration and, thereby, triggers a macrophage repolarization against fibrosis progression. This approach may provide a significant contribution to establish further nanotherapeutic delivery strategies to effectively treat liver fibrosis. Immune suppressive macrophages contribute to the progression of several diseases including cancer and fibrosis. Especially in chronically damaged liver tissues they trigger the replacement of functional parenchyma by collagen-dominating scare tissue. In this study, we aimed to intervene into this cascade by repolarizing the macrophage phenotype via a pH-degradable, squaric ester-based nanogel carrier system. This nanotechnology platform enables a selective covalent conjugation of the highly water-soluble bisphosphonate alendronate and, thus, its safe and efficient delivery to hepatic nonparenchymal cells of fibrotic livers after intravenous administration. The bisphosphonate triggers a reprogramming of profibrotic M2- towards antifibrotic M1-phenotype macrophages affording an fibrolytic outcome, as verified both on mRNA and protein level. Further insights by genomic and proteomic studies confirm the macrophages’ repolarization and thus corroborate the virtue of the nanogels as biocompatible nanocarrier platform for hepatotropic bisphosphonate delivery. Beyond preventing liver fibrosis progression, these nanogels may therefore represent an attractive device for further nanotherapeutic interventions in M2-type macrophage dominating diseases.

Project description:For successful therapeutic interventions in cancer immunotherapy, strong antigen-specific immune responses are required. To this end, immunostimulating cues must be combined with antigens to simultaneously arrive at antigen-presenting cells and initiate cellular immune responses. Recently, imidazoquinolines have shown their vast potential as small molecular Toll-like receptor 7/8 (TLR7/8) agonists for immunostimulation when delivered by nanocarriers. At the same time, peptide antigens are promising antigen candidates but require combination with immune-stimulating adjuvants to boost their immunogenicity and exploit their full potential. Consequently, we herein present biodegradable polycarbonate nanogels as versatile delivery system for adjuvants within the particles' core as well as for peptide antigens by surface decoration. For that purpose, orthogonally addressable multifunctional polycarbonate block copolymers were synthesized, enabling adjuvant conjugation through reactive ester chemistry and peptide decoration by strain-promoted alkyne-azide cycloaddition (SPAAC). In preparation for SPAAC, CD4+-specific peptide sequences of the model protein antigen ovalbumin were equipped with DBCO-moieties by site-selective modification at their N-terminal cysteine. With their azide groups exposed on their surface, the adjuvant-loaded nanogels were then efficiently decorated with DBCO-functional CD4+-peptides by SPAAC. In vitro evaluation of the adjuvant-loaded peptide-decorated gels then confirmed their strong immunostimulating properties as well as their high biocompatibility. Despite their covalent conjugation, the CD4+-peptide-decorated nanogels led to maturation of primary antigen-presenting cells and the downstream priming of CD4+-T cells. Subsequently, the peptide-decorated nanogels loaded with TLR7/8 agonist were successfully processed by antigen-presenting cells, enabling potent immune responses for future application in antigen-specific cancer immunotherapy.

Dataset Information

PH-degradable imidazoquinoline-ligated nanogels for lymph node-focused immune activation.

Publications

pH-degradable imidazoquinoline-ligated nanogels for lymph node-focused immune activation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets