Neuroimmune mechanisms in PTSD: inflammatory heterogeneity, circuit dysfunction, and biomarker-based subtypes

Area of Science:

• Neuroscience
• Immunology
• Psychiatry

Background:

• Post-traumatic stress disorder (PTSD) presents with complex symptoms and poorly understood molecular mechanisms.
• Dysregulation of the hypothalamic-pituitary-adrenal axis is a known factor, but glial-vascular and peripheral immune signaling roles are emerging.
• Clinical heterogeneity in PTSD suggests varied underlying neural circuit dysfunctions.

Purpose of the Study:

• To review the role of neuroimmune interactions in modulating neural circuits and network phenotypes in PTSD.
• To explore how peripheral immune signaling, endocrine regulation, and glial-vascular interactions influence PTSD.
• To connect immune-activated and immune-altered phenotypes to specific neural circuit dysfunctions in PTSD.

Main Methods:

• Integration of evidence from cytokine and immune cell profiling.
• Analysis of epigenetic and transcriptomic data.
• Review of experimental immune activation studies and neuroimaging, including translocator protein-positron emission tomography (TSPO-PET).

Main Results:

• Emerging evidence highlights inflammatory biomarkers (e.g., C-reactive protein, IL-6, TNF-α) and altered immune cell phenotypes in PTSD.
• Translocator protein-positron emission tomography (TSPO-PET) serves as a marker for glial activation.
• Neuroimmune interactions are implicated in modulating neural circuit function and synaptic plasticity.

Conclusions:

• Neuroimmune interfaces offer a framework for understanding PTSD heterogeneity.
• Peripheral immune markers combined with multimodal neuroimaging are crucial for validating underlying mechanisms.
• Further research into immune signaling, endocrine control, and neural networks is needed to elucidate PTSD pathophysiology.