Related Experiment Video
Updated: Jun 16, 2025

Screening Bioactive Nanoparticles in Phagocytic Immune Cells for Inhibitors of Toll-like Receptor Signaling
Published on: July 26, 2017
Synthetic polypeptides inhibit nucleic acid-induced inflammation in autoimmune diseases by disrupting multivalent
Xingliang Liu1,2, Shi Chen1, Jing Huang1,2
1School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Sun Yat-sen University, Guangzhou, China.
Abstract:
Complexes of extracellular nucleic acids (NAs) with endogenous proteins or peptides, such as LL37, break immune balance and cause autoimmune diseases, whereas NAs with arginine-enriched peptides do not. Inspired by this, we synthesize a polyarginine nanoparticle PEG-TK-NPArg, which effectively inhibits Toll-like receptor-9 (TLR9) activation, in contrast to LL37. To explore the discrepancy effect of PEG-TK-NPArg and LL37, we evaluate the periodic structure of PEG-TK-NPArg-NA and LL37-NA complexes using small-angle X-ray scattering. LL37-NA complexes have a larger inter-NA spacing that accommodates TLR9, while the inter-NA spacing in PEG-TK-NPArg-NA complexes mismatches with the cavity of TLR9, thus inhibiting an interaction with multiple TLR9s, limiting their clustering and damping immune induction. Subsequently, the inhibitory inflammation effect of PEG-TK-NPArg is proved in an animal model of rheumatoid arthritis. This work on how the scavenger-NA complexes inhibit the immune response may facilitate proof-of-concept research translating to clinical application.
Related Concept Videos
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Drugs for Treatment of Crohn's Disease in IBD Using Biologic Agents: Anti-TNF
Types of RNA
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Inflammatory Response
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
Eukaryotic Transcription Inhibitors
Eukaryotic transcription inhibitors usually contain two distinct domains, a...
Experimental RNAi

