Amyloid P component as a plasma marker for Parkinson's disease identified by a proteomic approach.

ABSTRACT

OBJECTIVES: Parkinson's disease (PD) ranks the second among the neurodegenerative disorders. Proteins involved in Parkinson's disease (PD) have been investigated but none as the diagnostic markers in blood. DESIGN AND METHODS: In this study, we applied a proteomic strategy, by utilizing two-dimensional electrophoresis and mass spectrometry, to analyze two sample pools of plasma from the healthy individuals and PD subjects. RESULTS: IgGκL and human serum amyloid P component (SAP) were found differentially expressed between these pools. SAP level increased by approximately 5-fold in PD samples, and the ELISA procedure revealed a significant (P<0.001) increase in SAP concentration (65.9 ± 18.7µg/mL) in the plasma of PD subjects (healthy individuals, 35.0 ± 12.5µg/mL), with sensitivity of 94.1% and specificity of 87.5%. CONCLUSION: Our results indicated a potential feasibility of plasma SAP as a marker to approach PD.