Peripheral Immune System in Individuals With Schizophrenia

Completed

• Conditions: Schizophrenia; Schizo Affective Disorder; Schizophreniform Disorders

• Registration Number: NCT05109065
• Lead Sponsor: Stanford University

Brief Summary

The investigators are seeking healthy volunteers and people with schizophrenia or schizoaffective disorder for a clinical study of the immune system in psychotic disorders. This is an observational study, to understand the ways in which the immune system may be contributing to the disease process.

Detailed Description

Genetic studies have linked the number of copies coding for C4 protein to risk for schizophrenia. Studies examining the amount of mRNA, the molecules that point to how much C4 protein is likely being made, found more C4 mRNA in the brains from individuals with schizophrenia. Studies in mice have suggested that expressing more C4 protein in the brain, specifically the A-type of C4, can result in abnormalities in behavior. However, researchers have also found that pathways that involve this protein in the blood to be abnormal in individuals even before they develop schizophrenia and hypothesize these abnormalities change the blood brain barrier. In this work, the researchers are hoping to understand the ways in which C4 protein is abnormal in the peripheral blood and how this may be contributing to the disease process in hopes of finding new ways of helping individuals with schizophrenia and possibly other mental health disorders. A major goal of this study is to collect blood tissue for ongoing translational study of pathophysiological mechanisms of schizophrenia.

Interested participants will be asked a series of questions about their medical and mental health history, be able to provide informed consent, undergo a urine toxicology screen and be willing to provide a blood sample.

Study Timeline

• Study Start: 2021-03-01
• Study First Submitted: 2021-10-26
• Study First Submitted QC: 2021-10-26
• Study First Posted: 2021-11-05
• Primary Completion: 2024-05-23
• Study Completion: 2024-05-23
• Status Verified: 2025-06
• Last Update Submitted: 2025-06-03
• Last Update Posted: 2025-06-06

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 63

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Group comparison of C4 protein in immune cells	Day 1	Measure the concentration of complement 4 protein in immune cells.

Secondary Outcome Measures

Name	Time	Method
Body Mass Index and its relationship to C4 protein concentration	Day 1	The relationship between body mass index, calculated from the measured height and weight of participants, and the primary outcome (C4 protein concentration) will be determined.
C4 Gene Copy Number	Day 1	Determine the C4 Gene Copy Number its relationship to C4 protein concentration in immune cells.
Relationship to symptom presentation	Day 1	Explore the relationship between clinical severity scores (PANSS) and the primary outcome.
Relationship to stress	Day 1	Explore the relationship between perceived stress (PSS) and the primary outcome.
C4 Activation	Day 1	Measure activity of C4 protein and its relationship to the primary outcome.

Trial Locations

Locations (1)

Stanford University School of Medicine; 🇺🇸 Stanford, California, United States