Common and disorder-specific upregulation of the inflammatory markers TRAIL and CCL20 in depression and schizophrenia

Relationship between inflammatory markers in human olfactory neural progenitor cells and antidepressant response

Response to antidepressants is related to hippocampal neurogenesis integrity, a process mediated by neurotrophins, such as Brain Derived Neurotrophic Factor (BDNF). In turn, pro-inflammatory state appears to reduce neurogenesis, and has been associated with refractory depressive states. We propose to analyze the human neural progenitor cells derived from the olfactory epithelium (HNPCs-OE) as an indicator of neurogenesis in humans. Therefore, we compared the number and content of HNPCs-OE in depressed patients taking antidepressants, according to response to treatment. Twenty depressed patients were followed during eight weeks after antidepressant treatment was prescribed. At the end evaluation they were divided in two groups according to Hamilton depression rating scale (HDRS) scores: responders and non-responders. We compared the number and components of HNPCs-OE between groups and observed an elevation of interleukine-8 in those patients who do not achieve response to treatment, BDNF levels were no related to antidepressant response.

Immunological protein profiling of first-episode psychosis patients identifies CSF and blood biomarkers correlating with disease severity

BACKGROUND AND HYPOTHESIS

Immune activation is suggested to play an important role in psychosis. In this study, a large number of immune-related proteins were analyzed to obtain a more comprehensive picture of immune aberrations in schizophrenia.

STUDY DESIGN

Ninety-two immune markers were analyzed by the Olink Protein Extension Assay (Inflammatory Panel) in plasma and cerebrospinal fluid (CSF) from 77 first-episode psychosis (FEP) patients (of which 43 later received the diagnosis of schizophrenia) and 56 healthy controls, all recruited from the Karolinska Schizophrenia Project (KaSP), Stockholm, Sweden.

STUDY RESULTS

Differential analysis showed that 12 of 92 inflammatory proteins were significantly higher in the plasma of FEP patients (n = 77) than in controls, and several proteins were positively correlated with disease severity. Patients from the same cohort diagnosed with schizophrenia (n = 43), showed significantly higher levels of 15 plasma proteins compared to controls whereas those not receiving this diagnosis showed no significant differences. The presently used OLINK inflammatory panel allowed the detection of only 47 CSF proteins of which only CD5 differed between patients and controls.

CONCLUSIONS

The levels of several peripheral immune markers, particularly those interfering with WNT/β-catenin signaling, were significantly higher in patients with FEP than in healthy controls and associated with illness severity.