Innovative Blood Test Identifies Glycan Marker Associated with Schizophrenia

Researchers from Nagoya University in Japan have developed a novel, highly sensitive blood test to measure polysialic acid, a distinctive acidic glycan predominantly found in the brain regions responsible for memory and emotion. Notably, this glycan fluctuates in the bloodstream of individuals with psychiatric conditions. Their innovative method employs a sandwich ELISA technique utilizing both positive and negative antibodies to detect polysialic acid accurately, overcoming previous challenges posed by its unique chemical properties.

This breakthrough revealed that levels of polysialic acid are notably elevated in the blood of patients diagnosed with schizophrenia, suggesting its potential as a diagnostic biomarker. Interestingly, similar increases were not observed in patients with chronic inflammatory demyelinating polyneuropathy, indicating that blood levels of this glycan could help differentiate between different neurological diseases.

Polysialic acid's main presence in brain areas related to memory and emotion makes it particularly relevant for neuropsychiatric disorders. Its detection in blood provides a promising avenue for developing non-invasive diagnostic tools, potentially improving early diagnosis and treatment planning.

The measurement technique is based on an enhanced sandwich ELISA method, which uses paired antibodies recognizing different structures of polysialic acid. The inclusion of a mutated negative antibody minimizes non-specific binding, significantly increasing measurement accuracy.

Further, the research points to broader implications, as elevated polysialic acid levels might also relate to other conditions like cancer, where tumor cells release substances into the bloodstream. The researchers believe understanding the mechanisms behind these changes could lead to new treatment strategies for various diseases.

This study, published in Scientific Reports, marks a significant step toward utilizing blood-based biomarkers for mental health and neurodegenerative disorders, opening new paths for research and clinical applications.