Finally, cluster of differentiation 14 (CD14), whose expression was increased in CSF from patients with Alzheimer’s disease (adjusted p = 5.9 × 10−3, logFC: 0.95, antibody ID: ab1393) and plasma from patients with Parkinson’s disease (adjusted p = 3.4 × 10−4), and osteopontin, whose expression was elevated in CSF from patients with Parkinson’s disease (adjusted p = 3.5 × 10−3, logFC: 0.83, antibody ID: ab1737), were selected for validation with quantitative ligand-binding assays (Figure 2A,B and Figure 3A,B). Here, SPP1 is linked to Alzheimer disease.