Soluble CD163 as a marker of macrophage activity in newly diagnosed patients with multiple sclerosis

Area of Science:

• Neuroimmunology
• Biomarker Discovery
• Clinical Diagnostics

Background:

• Soluble CD163 (sCD163), a macrophage-specific protein, is elevated in the serum of multiple sclerosis (MS) patients.
• This study investigates sCD163 in both serum and cerebrospinal fluid (CSF) for diagnostic potential in MS.

Purpose of the Study:

• To evaluate sCD163 levels in serum and CSF of patients undergoing MS diagnostic work-up.
• To determine the utility of sCD163 as a diagnostic biomarker for multiple sclerosis.

Main Methods:

• Enzyme-linked immunosorbent assay (ELISA) was used to measure sCD163 levels in paired serum and CSF samples from 183 patients.
• Patients were categorized based on diagnostic outcomes, including a symptomatic control group with normal findings.

Main Results:

• sCD163 was measurable in all serum and CSF samples.
• A high CSF/serum sCD163 ratio was observed, suggesting local central nervous system (CNS) production.
• Median sCD163 levels were significantly decreased in serum and elevated in CSF for relapsing-remitting and primary-progressive MS patients.
• Receiver operating characteristic (ROC) analysis yielded an area under the curve of 0.72 for the sCD163 CSF/serum ratio.

Conclusions:

• The elevated sCD163 CSF/serum ratio in MS patients suggests macrophage activation within MS lesions.
• These findings indicate that primary progressive MS is inflammation-driven, involving the innate immune system.
• sCD163 shows promise as a biomarker for diagnosing and understanding the inflammatory processes in multiple sclerosis.