simoa assays  (Quanterix)

Journal: The Journal of Prevention of Alzheimer's Disease

Article Title: Plasma GFAP outperforms CSF GFAP in detecting amyloid pathology and is associated with increased risk of clinical progression in early Alzheimer’s disease

doi: 10.1016/j.tjpad.2026.100544

Figure Lengend Snippet: Biomarker Levels in Plasma and CSF across Different Groups. (A) Plasma GFAP (Glial Fibrillary Acidic Protein) levels (pg/ml) across subject groups, including healthy controls (Ctrl), relatives of Alzheimer’s disease patients (AD-rel), subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer’s disease (AD). Both the MCI and AD groups show significantly higher GFAP levels compared to controls (*p < 0.05, **p < 0.01, ***p < 0.001). (B) CSF GFAP (ng/ml) levels in the same groups. GFAP concentrations in both MCI and AD are also significantly higher than in controls (*p < 0.05, **p < 0.01, *p < 0.001).

Article Snippet: Approximately one hour before analysis, samples were thawed at room temperature and centrifuged for 10 min at 10.000 g. Plasma levels of GFAP were quantitated using the Simoa® GFAP Discovery Kit (PN 102,336, Quanterix, Billerica, MA, USA) on a SIMOA HD-X platform.

Techniques: Biomarker Discovery, Clinical Proteomics

Journal: The Journal of Prevention of Alzheimer's Disease

Article Title: Plasma GFAP outperforms CSF GFAP in detecting amyloid pathology and is associated with increased risk of clinical progression in early Alzheimer’s disease

doi: 10.1016/j.tjpad.2026.100544

Figure Lengend Snippet: Biomarker Levels in Plasma and CSF Based on Amyloid-β Status. (A) Plasma GFAP levels (pg/ml) in the same groups. Plasma GFAP concentrations in SCD-A+, MCI-A+, and AD-A+ are significantly higher than in controls and their respective A− counterparts. (B) CSF GFAP (Glial Fibrillary Acidic Protein) levels (ng/ml) across subject groups categorized by amyloid-β negative (A−) and positive (A+) status, including healthy controls (Ctrl), subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer’s disease (AD). No significant differences were observed between A− and A+ groups in any category (p > 0.05) (*p < 0.05, **p < 0.01, ***p < 0.001).

Article Snippet: Approximately one hour before analysis, samples were thawed at room temperature and centrifuged for 10 min at 10.000 g. Plasma levels of GFAP were quantitated using the Simoa® GFAP Discovery Kit (PN 102,336, Quanterix, Billerica, MA, USA) on a SIMOA HD-X platform.

Techniques: Biomarker Discovery, Clinical Proteomics

Journal: The Journal of Prevention of Alzheimer's Disease

Article Title: Plasma GFAP outperforms CSF GFAP in detecting amyloid pathology and is associated with increased risk of clinical progression in early Alzheimer’s disease

doi: 10.1016/j.tjpad.2026.100544

Figure Lengend Snippet: Receiver Operating Characteristic (ROC) Curves for prediction of amyloid positivity. (A) ROC curves comparing CSF GFAP, plasma GFAP alone, and plasma GFAP combined with age and ApoE4 in the total cohort. Plasma GFAP alone showed moderate discrimination (AUC: 0.73 [0.68–0.78]), whereas CSF GFAP showed lower performance (AUC: 0.55 [0.49–0.60]). The combined model including plasma GFAP, age, and ApoE4 demonstrated the highest classification accuracy (AUC: 0.84 [0.81–0.88]). (B) ROC curves comparing plasma GFAP + age (AUC: 0.76 [0.71–0.81]), plasma GFAP + ApoE4 (AUC: 0.82 [0.78–0.86]), age + ApoE4 (AUC: 0.82 [0.78–0.85]), age alone (AUC: 0.69 [0.65–0.74]), and ApoE4 alone (AUC: 0.63 [0.58–0.68]) for prediction of amyloid positivity. (C) ROC curves for plasma GFAP alone in individual diagnostic groups. Discriminatory performance varied across groups, with AUCs of 0.64 [0.47–0.82] for controls, 0.64 [0.55–0.73] for SCD, 0.77 [0.68–0.86] for MCI, and 0.81 [0.59–1.00] for AD. (D) ROC curves for plasma GFAP combined with age and ApoE4 within individual diagnostic groups. The combined model yielded AUCs of 0.77 [0.62–0.91] for controls, 0.79 [0.71–0.86] for SCD, 0.87 [0.79–0.95] for MCI, and 0.72 [0.29–1.00] for AD.

Article Snippet: Approximately one hour before analysis, samples were thawed at room temperature and centrifuged for 10 min at 10.000 g. Plasma levels of GFAP were quantitated using the Simoa® GFAP Discovery Kit (PN 102,336, Quanterix, Billerica, MA, USA) on a SIMOA HD-X platform.

Techniques: Clinical Proteomics, Diagnostic Assay

Journal: The Journal of Prevention of Alzheimer's Disease

Article Title: Plasma GFAP outperforms CSF GFAP in detecting amyloid pathology and is associated with increased risk of clinical progression in early Alzheimer’s disease

doi: 10.1016/j.tjpad.2026.100544

Figure Lengend Snippet: Plasma GFAP increases the amyloid-independent risk of clinical progression to MCI and dementia. (A) ROC curve of plasma GFAP differentiating AD from controls (AUC = 0.864). The optimal threshold (229 pg/ml), determined using the Youden index, yielded a sensitivity of 0.785 and a specificity of 0.833. (B) Distribution of plasma GFAP concentrations across diagnostic groups (Control, SCD, MCI, and AD). The dashed horizontal line indicates the ROC-derived optimal cutoff (229 pg/ml) used for subsequent survival analyses. (C) Kaplan–Meier curves for conversion to MCI stratified by plasma GFAP levels, showing faster conversion in the high-GFAP group (unadjusted HR = 2.19, 95 % CI: 1.53–3.14; adjusted HR = 1.70, 95 % CI: 1.17–2.47). (D) Kaplan–Meier curves for conversion to dementia, demonstrating a markedly increased progression risk in participants with high plasma GFAP (unadjusted HR = 3.5, 95 % CI: 2.17–5.65; adjusted HR = 2.49, 95 % CI: 1.52–4.08).

Article Snippet: Approximately one hour before analysis, samples were thawed at room temperature and centrifuged for 10 min at 10.000 g. Plasma levels of GFAP were quantitated using the Simoa® GFAP Discovery Kit (PN 102,336, Quanterix, Billerica, MA, USA) on a SIMOA HD-X platform.

Techniques: Clinical Proteomics, Diagnostic Assay, Control, Derivative Assay