Preclinical development of an immunoassay for the detection of TREM2: a new biomarker for Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tangles composed of hyperphosphorylated tau protein. The combination of biomarkers is crucial for AD diagnosis. The triggering receptor expressed on myeloid cells 2 (TREM2), a receptor expressed on microglia, is important in AD pathogenesis. Impairment of TREM2 function aggravates the toxic effects of amyloid plaques, and its activation has been shown to reduce Aβ burden and memory deficits. Increased levels of soluble TREM2 (sTREM2) in blood and cerebrospinal fluid is associated with AD. Therefore, TREM2 could serve as a non-invasive biomarker for AD. In this study, we developed a preclinical immunoassay to detect TREM2 for AD diagnosis. Highly sensitive and specific TREM2 antibodies were produced using the hybridoma technique. The three optimized immunoassays exhibited lower limit of quantitation (LLOQ) of 0.474, 0.807, and 0.415 ng/mL, respectively. These preclinical immunoassays showed high sensitivity and specificity. The sandwich enzyme-linked immunosorbent assay (ELISA) could potentially be used for AD diagnosis.