HLA-DR expression and neopterin levels as activity markers in multiple sclerosis

Area of Science:

• Neuroimmunology
• Clinical Immunology

Background:

• Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS).
• Assessing disease activity in MS is crucial for effective management and therapeutic monitoring.

Purpose of the Study:

• To evaluate the utility of T cells expressing human leukocyte antigen (HLA)-DR in cerebrospinal fluid (CSF) as a marker of disease activity in MS.
• To investigate the potential of neopterin levels in CSF as an objective marker for monitoring MS disease activity.

Main Methods:

• A double-immunofluorescence labeling assay was used to detect HLA-DR expression on T cells in prefixed CSF and peripheral blood mononuclear cells from MS patients.
• Neopterin levels in CSF and serum were measured in MS patients during exacerbations and remissions, and in patients with acute aseptic meningo-encephalitis (AM).

Main Results:

• No accumulation of HLA-DR expressing T cells was observed in the CSF of MS patients.
• Patients with acute aseptic meningo-encephalitis (AM) showed an accumulation of activated, HLA-DR positive T cells in CSF, indicating active CNS immunity.
• Neopterin levels were significantly elevated in the CSF of MS patients during clinical exacerbations compared to remissions, with no corresponding elevation in serum.
• Elevated neopterin levels in CSF were also observed during the acute phase of AM, normalizing after recovery.

Conclusions:

• Enumeration of HLA-DR expressing T cells in CSF is not a reliable indicator of disease activity in MS.
• Neopterin levels in CSF serve as a valuable marker of acute cellular immune responses and can objectively monitor disease activity in MS.
• Neopterin measurement in CSF holds potential for evaluating the efficacy of therapeutic agents in MS.