Affordable Access

deepdyve-link
Publisher Website

High-relaxivity superparamagnetic iron oxide nanoworms with decreased immune recognition and long-circulating properties.

Authors
  • Wang, Guankui
  • Inturi, Swetha
  • Serkova, Natalie J
  • Merkulov, Sergey
  • McCrae, Keith
  • Russek, Stephen E
  • Banda, Nirmal K
  • Simberg, Dmitri
Type
Published Article
Journal
ACS Nano
Publisher
American Chemical Society
Publication Date
Dec 23, 2014
Volume
8
Issue
12
Pages
12437–12449
Identifiers
DOI: 10.1021/nn505126b
PMID: 25419856
Source
Medline
Keywords
License
Unknown

Abstract

One of the core issues of nanotechnology involves masking the foreignness of nanomaterials to enable in vivo longevity and long-term immune evasion. Dextran-coated superparamagnetic iron oxide nanoparticles are very effective magnetic resonance imaging (MRI) contrast agents, and strategies to prevent immune recognition are critical for their clinical translation. Here we prepared 20 kDa dextran-coated SPIO nanoworms (NWs) of 250 nm diameter and a high molar transverse relaxivity rate R2 (∼400 mM(-1) s(-1)) to study the effect of cross-linking-hydrogelation with 1-chloro-2,3-epoxypropane (epichlorohydrin) on the immune evasion both in vitro and in vivo. Cross-linking was performed in the presence of different concentrations of NaOH (0.5 to 10 N) and different temperatures (23 and 37 °C). Increasing NaOH concentration and temperature significantly decrease the binding of anti-dextran antibody and dextran-binding lectin conconavalin A to the NWs. The decrease in dextran immunoreactivity correlated with the decrease in opsonization by complement component 3 (C3) and with the decrease in the binding of the lectin pathway factor MASP-2 in mouse serum, suggesting that cross-linking blocks the lectin pathway of complement. The decrease in C3 opsonization correlated with the decrease in NW uptake by murine peritoneal macrophages. Optimized NWs demonstrated up to 10 h circulation half-life in mice and minimal uptake by the liver, while maintaining the large 250 nm size in the blood. We demonstrate that immune recognition of large iron oxide nanoparticles can be efficiently blocked by chemical cross-linking-hydrogelation, which is a promising strategy to improve safety and bioinertness of MRI contrast agents.

Report this publication

Statistics

Seen <100 times