Quantification of blood glial fibrillary acidic protein using a second-generation microfluidic assay. Validation and comparative analysis with two established assays

© 2024 the author(s), published by De Gruyter, Berlin/Boston..

OBJECTIVES: Increased levels of glial fibrillary acidic protein (GFAP) in blood have been identified as a valuable biomarker for some neurological disorders, such as Alzheimer's disease and multiple sclerosis. However, most blood GFAP quantifications so far were performed using the same bead-based assay, and to date a routine clinical application is lacking.

METHODS: In this study, we validated a novel second-generation (2nd gen) Ella assay to quantify serum GFAP. Furthermore, we compared its performance with a bead-based single molecule array (Simoa) and a homemade GFAP assay in a clinical cohort of neurological diseases, including 210 patients.

RESULTS: Validation experiments resulted in an intra-assay variation of 10 %, an inter-assay of 12 %, a limit of detection of 0.9 pg/mL, a lower limit of quantification of 2.8 pg/mL, and less than 20 % variation in serum samples exposed to up to five freeze-thaw cycles, 120 h at 4 °C and room temperature. Measurement of the clinical cohort using all assays revealed the same pattern of GFAP distribution in the different diagnostic groups. Moreover, we observed a strong correlation between the 2nd gen Ella and Simoa (r=0.91 (95 % CI: 0.88-0.93), p<0.0001) and the homemade immunoassay (r=0.77 (95 % CI: 0.70-0.82), p<0.0001).

CONCLUSIONS: Our results demonstrate a high reliability, precision and reproducibility of the 2nd gen Ella assay. Although a higher assay sensitivity for Simoa was observed, the new microfluidic assay might have the potential to be used for GFAP analysis in daily clinical workups due to its robustness and ease of use.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - year:2024

Enthalten in:

Clinical chemistry and laboratory medicine - (2024) vom: 07. Feb.

Sprache:

Englisch

Beteiligte Personen:

Fazeli, Badrieh [VerfasserIn]
Gómez de San José, Nerea [VerfasserIn]
Jesse, Sarah [VerfasserIn]
Senel, Makbule [VerfasserIn]
Oeckl, Patrick [VerfasserIn]
Erhart, Deborah K [VerfasserIn]
Ludolph, Albert C [VerfasserIn]
Otto, Markus [VerfasserIn]
Halbgebauer, Steffen [VerfasserIn]
Tumani, Hayrettin [VerfasserIn]

Links:

Volltext

Themen:

Alzheimer’s disease
Blood biomarker
GFAP
Journal Article
Microfluidic assay
Multiple sclerosis

Anmerkungen:

Date Revised 03.04.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1515/cclm-2023-1256

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM368432564