Binding of human IgG to single-walled carbon nanotubes accelerated myeloperoxidase-mediated degradation in activated neutrophils.
The binding of protein to carboxylated single-walled carbon nanotubes (SWCNTs) was believed to play an important role in the biological effects of nanotubes. However, the effects of protein-SWCNTs interactions on the oxidative degradation of nanotubes were not stressed enough. Here, we investigated the binding of human immunoglobulin G (IgG) to SWCNTs, and found that the preferred binding site was located in the Fcregion of IgG. The hydrophobic and electrostatic interactions might be the crucial factors in stabilizing the binding of SWCNTs with IgG. Through the competitive binding of IgG and myeloperoxidase (MPO) to nanotube surfaces, the binding of IgG could impair MPO-induced SWCNTs biodegradation in vitro. However, both SWCNTs and IgG-SWCNTs were significantly degraded in zymosan-stimulated neutrophils, and the degradation degree was more for IgG-SWCNTs. These results suggest that the binding of IgG may be an important determinant for MPO-mediated SWCNTs biodegradation in activated human inflammatory cells.
Key Laboratory of Functional Small Organic Molecule, Ministry of Education, Key Laboratory of Green Chemistry, Jiangxi Province, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, China.
Yun
Y
Ding
Key Laboratory of Functional Small Organic Molecule, Ministry of Education, Key Laboratory of Green Chemistry, Jiangxi Province, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, China.
Rong
R
Tian
Department of Physics, University of Houston, Houston, TX, USA.
Zhen
Z
Yang
Department of Physics, University of Houston, Houston, TX, USA.
Jianfa
J
Chen
Key Laboratory of Functional Small Organic Molecule, Ministry of Education, Key Laboratory of Green Chemistry, Jiangxi Province, College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, China. Electronic address: naihaolu@jxnu.edu.cn.
Naihao
N
Lu
D001665:Binding Sites; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007074:Immunoglobulin G / Q000378:metabolism*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D018375:Neutrophil Activation; D009504:Neutrophils / Q000378:metabolism*; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism*; D011485:Protein Binding; D015054:Zymosan / Q000494:pharmacology
D007074:Immunoglobulin G; D037742:Nanotubes, Carbon; D015054:Zymosan; D009195:Peroxidase
Biodegradation; Human IgG; Myeloperoxidase; Neutrophils; Single-walled carbon nanotubes