RESUMEN
BACKGROUND: Alzheimer's disease (AD) is an age-related chronic degenerative disease that damages the nervous system. A noninvasive and simple method for early detection of AD is extremely important for the diagnosis and prognosis of AD. Thus, we aimed to develop an enzyme-linked immunosorbent assay (ELISA) kit to detect urine Alzheimer-associated neuronal thread protein (AD7C-NTP), and to evaluate its clinical value for the diagnosis of AD. METHODS: Immunogenic AD7C-NTP peptide fragments were synthesized by the solid-phase method and used for immunizing mice or rabbits to generate anti-AD7C-NTP antibodies. The urine AD7C-NTP ELISA kit was then established; the generated mouse anti-AD7C-NTP antibody was used as a capture antibody, the biotin-labeled rabbit anti-AD7C-NTP antibody was used as a detection antibody, and avidin labeled by horseradish peroxidase was used as a substrate. The first morning urine specimens of 121 AD patients and 118 age-matched controls were collected, and the urine AD7C-NTP levels were detected by the above ELISA kit. RESULTS: Mouse and rabbit anti-AD7C-NTP antibody ELISA titer was found to be 1:8,000 and 1:32,000, respectively. A single band with a relative molecular mass of 41 kDa was found in human brain specimens by Western blot assay, which was identified as AD7C-NTP antibody. The urine AD7C-NTP concentration of the AD patients was higher than that of the age-matched controls, the sensitivity was 89.3% and the specificity was 84.7%. CONCLUSIONS: Our study demonstrated that our newly developed urine AD7C-NTP ELISA kit has suggested potential for diagnosing AD in a Chinese population, suggesting it may be a useful diagnostic kit for detecting early AD.