Acute Immunological Phenotypes in Individuals with Traumatic Spinal Cord Injury.

Area of Science:

• Immunology
• Neuroscience
• Genomics

Background:

• Traumatic spinal cord injury (SCI) initiates an inflammatory response, exacerbating secondary damage and systemic inflammation.
• This systemic inflammation contributes to long-term health complications following SCI.

Purpose of the Study:

• To investigate acute cellular and molecular immune system alterations in individuals with SCI within 0-4 days post-injury.
• To compare these changes against uninjured control individuals.

Main Methods:

• Bulk RNA sequencing of blood samples from SCI patients (N=36) and controls (N=36).
• Complete blood count analysis and flow cytometry to assess immune cell populations.
• Measurement of inflammatory biomarkers like C-reactive protein and cytokines.

Main Results:

• Identified 4752 differentially expressed genes in SCI patients, notably those linked to inflammation and innate immunity (e.g., Neutrophil degranulation, Toll-Like Receptor signaling).
• Observed elevated white blood cell, neutrophil, and monocyte counts, alongside lymphopenia in a significant portion of SCI patients.
• Found reduced expression of genes associated with natural killer (NK) cells, T cells, and dendritic cells (DCs), correlating with decreased cell frequencies.
• Noted elevated C-reactive protein and pro-inflammatory cytokines (e.g., HMGB1, IL-6, IL-8), with higher levels in motor-complete injuries.

Conclusions:

• Acute SCI induces profound systemic immunological changes, including inflammation and altered immune cell profiles.
• These molecular and cellular changes serve as potential biomarkers for SCI severity.
• The identified immunological alterations represent potential therapeutic targets for improving health outcomes after SCI.