Complement Profiles in Patients with Amyotrophic Lateral Sclerosis: A Prospective Observational Cohort Study

Area of Science:

• Neuroimmunology
• Complement System Biology

Background:

• The complement system is implicated in amyotrophic lateral sclerosis (ALS) pathophysiology.
• This study investigates complement markers in ALS patients.

Purpose of the Study:

• To compare complement marker levels in ALS patients versus controls.
• To analyze the association between complement markers and ALS clinical outcomes, including survival.

Main Methods:

• Observational, explorative cohort study of 92 ALS patients, 61 neurological controls, and 96 healthy controls.
• Measurement of ficolin-1, -2, -3, collectin-11, MBL, MASP-3, MAP-1, C4, C3, PTX-3, C4c, C3bc, and sC5b-9 in plasma and cerebrospinal fluid (CSF).
• Clinical outcomes, including survival, were recorded for 24-48 months.

Main Results:

• ALS patients had increased plasma collectin-11, C4, sC5b-9, and CSF ficolin-3 compared to controls.
• Plasma ficolin-2 was decreased in ALS patients versus healthy controls.
• Collectin-11, C3, and C3bc levels correlated negatively with ALSFRS-R; no survival association was found.

Conclusions:

• ALS patients display aberrant lectin pathway mediators and terminal pathway activation.
• These findings support the involvement of the complement system in ALS pathophysiology.