HMGB1 expression patterns during the progression of experimental autoimmune encephalomyelitis

Area of Science:

• Neuroimmunology
• Cellular Biology
• Protein Dynamics

Background:

• High mobility group box 1 (HMGB1) is a chromatin-associated protein with diverse cellular functions.
• Systemic HMGB1 has been linked to autoimmune encephalomyelitis (EAE).
• Dynamic changes in spinal cord HMGB1 expression during EAE are not fully understood.

Purpose of the Study:

• To investigate the dynamic changes in HMGB1 expression patterns within the spinal cord during experimental autoimmune encephalomyelitis (EAE).
• To correlate HMGB1 alterations with disease progression and severity.
• To evaluate the therapeutic potential of targeting HMGB1 in EAE.

Main Methods:

• Analysis of HMGB1 amount, cell location, and subcellular localization in adult mouse spinal cords at various EAE stages.
• Immunohistochemical staining to identify HMGB1-expressing cells (astrocytes, microglia, neurons).
• Assessment of HMGB1 blockade effects on EAE severity within the central nervous system (CNS).

Main Results:

• In normal conditions, HMGB1 is primarily nuclear in spinal cord resident cells.
• During EAE, total and extracellular HMGB1 increase significantly in the spinal cord.
• HMGB1-positive astrocytes and microglia increase, and neuronal HMGB1 shifts to the cytoplasm, correlating with increased extracellular HMGB1.
• Local blockade of HMGB1 within the CNS markedly reduces EAE severity.

Conclusions:

• Spinal cord HMGB1 expression patterns dynamically change during EAE progression.
• Altered HMGB1 localization and increased extracellular levels are associated with EAE.
• Targeting HMGB1 within the CNS offers a promising therapeutic strategy for autoimmune encephalomyelitis, potentially relevant for multiple sclerosis.