Comparison of GFAP and UCH-L1 Measurements from Two Prototype Assays: The Abbott i-STAT and ARCHITECT Assays

• Published in: Neurotrauma reports Vol. 2; no. 1; pp. 193 - 199
• Main Authors: Korley, Frederick K, Datwyler, Saul A, Jain, Sonia, Sun, Xiaoying, Beligere, Gangamani, Chandran, Raj, Marino, Jaime A, McQuiston, Beth, Zhang, Hongwei, Caudle, Krista L, Wang, Kevin K W, Puccio, Ava M, Okonkwo, David O, Yue, John K, Taylor, Sabrina R, Markowitz, Amy, Manley, Geoffrey T, Diaz-Arrastia, Ramon
• Format: Journal Article
• Language: English
• Published: 140 Huguenot Street, 3rd FloorNew Rochelle, NY 10801USA Mary Ann Liebert, Inc., publishers 01.04.2021; Mary Ann Liebert
• Subjects: assay; biomarkers; glial fibrillary acidic protein; Original; Original Article; traumatic brain injury; ubiquitin carboxyl-terminal hydrolase L1; traumatic brain injury; ubiquitin carboxyl-terminal hydrolase L1; assay; glial fibrillary acidic protein; biomarkers
• ISSN: 2689-288X; 2689-288X
• DOI: 10.1089/neur.2020.0037

Glial fibrillary acidic protein (GFAP) and ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) may aid in the evaluation of traumatic brain injury (TBI). The objective of this analysis was to compare GFAP and UCH-L1 values measured using a handheld device compared with a core laboratory platform. We analyzed plasma samples from patients with TBI and healthy controls enrolled in the T ransforming R esearch a nd C linical K nowledge in TBI (TRACK-TBI) cohort study. GFAP and UCH-L1 were measured twice in each subject using prototype assays, first with the Abbott i-STAT™ handheld device, and second with the Abbott ARCHITECT ® platform. We then quantified the agreement in biomarker values obtained using these two methods. GFAP and UCH-L1 were measured twice in 570 and 572 samples, respectively. GFAP values measured by the ARCHITECT platform (median 143.3 [interquartile range (IQR): 19.8–925.8] pg/mL) were higher than values measured by the i-STAT (median 116.0 [IQR: 9.2–856.5] pg/mL). GFAP values from the two platforms were strongly correlated ( p  = 0.985). Similarly, UCH-L1 values measured by the ARCHITECT platform (median 163.9 [IQR: 82.5–412.4] pg/mL) were higher than values measured by the i-STAT (median 122.5 [IQR: 63.0–297.3] pg/mL). UCH-L1 values from the two platforms were strongly correlated ( p  = 0.933). Passing-Bablok regression equations were developed to estimate the relationship between the two platforms, specifically to predict i-STAT values from the ARCHITECT platform. GFAP and UCH-L1 values measured using the prototype assays on the Abbott i-STAT and ARCHITECT platforms are strongly correlated and values from either platform may be converted to the other.