An antibody microarray analysis of serum cytokines in neurodegenerative Parkinsonian syndromes

Background Microarray technology may offer a new opportunity to gain insight into disease-specific global protein expression profiles. The present study was performed to apply a serum antibody microarray to screen for differentially regulated cytokines in Parkinson's disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). Results Serum samples were obtained from patients with clinical diagnoses of PD (n = 117), MSA (n = 31) and PSP/CBS (n = 38) and 99 controls. Cytokine profiles of sera from patients and controls were analyzed with a semiquantitative human antibody array for 174 cytokines and the expression of 12 cytokines was found to be significantly altered. In a next step, results from the microarray experiment were individually validated by different immunoassays. Immunoassay validation confirmed a significant increase of median PDGF-BB levels in patients with PSP/CBS, MSA and PD and a decrease of median prolactin levels in PD. However, neither PDGF-BB nor prolactin were specific biomarkers to discriminate PSP/CBS, MSA, PD and controls. Conclusions In our unbiased cytokine array based screening approach and validation by a different immunoassay only two of 174 cytokines were significantly altered between patients and controls.