Anti-aquaporin-4 immunoglobulin G colorimetric detection by silver nanoparticles

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory and autoimmune disease whose biomarker is the anti-AQP4-IgG autoantibody that binds to aquaporin-4 (AQP4) protein. We introduced a nanosensor with a sensitivity of 84.6%, higher than the CBA's 76.5%. Using silver nanoparticles (A...

Full description

Saved in:
Bibliographic Details
Published in:Nanomedicine 2022-04, Vol.41, p.102531-102531, Article 102531
Main Authors: Higa, Akemi M., Moraes, Ariana S., Shimizu, Flávio M., Bueno, Raquel G., Peroni, Luís A., Strixino, Francisco T., Sousa, Nise A.C., Deffune, Elenice, Bovolato, Ana Lívia C., Oliveira, Osvaldo N., Brum, Doralina G., Leite, Fabio L.
Format: Article
Language:English
Subjects:
Anti-aquaporin-4 immunoglobulin G
Aquaporin 4
Colorimetry
Diagnosis
Epitopes
Humans
Immunoglobulin G
Metal Nanoparticles
Neuromyelitis Optica - diagnosis
Neuromyelitis optica spectrum disorders
Silver
Silver nanoparticles
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory and autoimmune disease whose biomarker is the anti-AQP4-IgG autoantibody that binds to aquaporin-4 (AQP4) protein. We introduced a nanosensor with a sensitivity of 84.6%, higher than the CBA's 76.5%. Using silver nanoparticles (AgNPs), we detected not only seropositive but also some false-negative patients previously classified with CBA. It consisted of AgNPs coated with one of a panel of 5 AQP4 epitopes. The ability in detecting the anti-AQP4-IgG in NMOSD patients depended on the epitope and synergy could be obtained by combining different epitopes. We demonstrated that NMOSD patients could easily be distinguished from healthy subjects and patients with multiple sclerosis. Using the most sensitive AQP461-70 peptide, we established a calibration curve to estimate the concentration of anti-AQP4-IgG in seropositive NMOSD patients. The ability to enhance the accuracy of the diagnosis may improve the prognosis of 10-27% of anti-AQP4-IgG seronegative patients worldwide. Schematic diagram of the interaction mechanism of the AQP4-peptide conjugated AgNPs with IgG samples. When a serum sample containing the anti-AQP4-IgG is added to the AgNPs suspension, the target antibody promotes nanoparticle aggregation, evidenced by color changing from yellow to orange-red variations, associated with the appearance of new LSPR bands in the UV–vis absorption spectrum, at longer wavelengths and 360 nm. The maintenance of suspension original color (yellow) and one single LSPR band characterize the non-specific response of the AQP4-peptide conjugated AgNPs after interaction with serum samples without the anti-AQP4-IgG autoantibody. [Display omitted] •Prognosis of AQP4-IgG CBA seronegative patients may be improved with our approach.•AQP4-IgG detection was reached with a low-cost nanoparticle colorimetric method.•High accuracy was reached with a judicious choice of AQP4 target epitopes.•AQP4 epitope targets differ in patients with distinct clinical diagnosis of NMOSD.
ISSN:1549-9634
1549-9642
DOI:10.1016/j.nano.2022.102531