Therapeutic albumin binding to remove amyloid-β

Area of Science:

• Neuroscience
• Biochemistry
• Pharmacology

Background:

• Alzheimer's disease (AD) is characterized by amyloid-beta (Aβ) accumulation.
• Plasma exchange with therapeutic albumin is a novel AD treatment strategy to enhance Aβ clearance.
• Characterizing albumin's Aβ binding capacity is essential for this therapeutic approach.

Purpose of the Study:

• To determine the Aβ binding capacity of Grifols' therapeutic albumin (Albutein®).
• To quantify endogenous Aβ levels in Albutein®.
• To assess Albutein®'s interaction with synthetic Aβ40 and Aβ42 peptides.

Main Methods:

• Quantification of Aβ40 and Aβ42 using ELISA and Araclon ABtest®.
• Assessment of Aβ binding via ELISA with serially diluted albumin and synthetic Aβ peptides.
• Surface plasmon resonance (SPR) analysis for sAβ42 binding kinetics.

Main Results:

• Albutein® showed undetectable levels of endogenous Aβ40 and Aβ42.
• Albumin concentration-dependent reduction in exogenously added sAβ42 was observed (59-78%).
• Albutein® demonstrated significant binding to sAβ40 (∼60% recovery) and sAβ42 (∼70% recovery), with a KD of 1.72 × 10⁻⁶ M for sAβ42.

Conclusions:

• Grifols' therapeutic albumin (Albutein®) contains no detectable Aβ.
• Albutein® exhibits consistent binding affinity for human Aβ peptides.
• These findings support the therapeutic potential of Albutein® in Alzheimer's disease management via enhanced Aβ efflux.