A highly specific and sensitive nanoimmunosensor for the diagnosis of neuromyelitis optica spectrum disorders

• Autor(a) principal: Moraes, Ariana de Souza
• Data de Publicação: 2019
• Outros Autores: Brum, Doralina Guimaraes [UNESP], Magalhaes Ierich, Jessica Cristiane, Higa, Akemi Martins, Jabur Assis, Amanda Stefanie, Miyazaki, Celina Massumi, Shimizu, Flavio Makoto, Peroni, Luis Antonio, Machini, M. Teresa, Barreira, Amilton Antunes, Ferreira, Marystela, Oliveira Jr, Osvaldo N., Leite, Fabio Lima
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1038/s41598-019-52506-w; http://hdl.handle.net/11449/196300

A precise diagnosis for neuromyelitis optica spectrum disorders (NMOSD) is crucial to improve patients' prognostic, which requires highly specific and sensitive tests. The cell-based assay with a sensitivity of 76% and specificity of 100% is the most recommended test to detect anti-aquaporin-4 antibodies (AQP4-Ab). Here, we tested four AQP4 external loop peptides (AQP4(61-70), AQP4(131-140), AQP4(141-150), and AQP4(201-210)) with an atomic force microscopy nanoimmunosensor to develop a diagnostic assay. We obtained the highest reactivity with AQP4(61-70)-nanoimunosensor. This assay was effective in detecting AQP4-Ab in sera of NMOSD patients with 100% specificity (95% CI 63.06-100), determined by the cut-off adhesion force value of 241.3 pN. NMOSD patients were successfully discriminated from a set of healthy volunteers, patients with multiple sclerosis, and AQP4-Ab-negative patients. AQP4(61-70) sensitivity was 81.25% (95% CI 56.50-99.43), slightly higher than with the CBA method. The results with the AQP4(61-70)-nanoimmunosensor indicate that the differences between NMOSD seropositive and seronegative phenotypes are related to disease-specific epitopes. The absence of AQP4-Ab in sera of NMOSD AQP4-Ab-negative patients may be interpreted by assuming the existence of another potential AQP4 peptide sequence or non-AQP4 antigens as the antibody target.