Covalent immobilization of human serum albumin on cellulose acetate membrane for scavenging amyloid beta – A stepping extracorporeal strategy for ameliorating Alzheimer’s disease

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2024-02, Vol.234, p.113753-113753, Article 113753
• Main Authors: Ullah, Aziz, Lee, Gyu-Jin, Kwon, Hyuk Taek, Lim, Sung In
• Format: Article
• Language: English
• Subjects: Alzheimer’s disease; Amyloid-β; Extracorporeal treatment; Green fluorescent protein; Human serum albumin; Protein immobilization
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2024.113753

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by interrupted neurocognitive functions and impaired mental development presumably caused by the accumulation of amyloid beta (Aβ) in the form of plaques. Targeting Aβ has been considered a promising approach for treating AD. In the current study, human serum albumin (HSA), a natural Aβ binder, is covalently immobilized onto the surface of a cellulose acetate (CA) membrane to devise an extracorporeal Aβ sequester. The immobilization of HSA at 3.06 ± 0.22 μg/mm2 of the CA membrane was found to be active functionally, as evidenced by the esterase-like activity converting p-nitrophenyl acetate into p-nitrophenol. The green fluorescent protein–Aβ (GFP–Aβ) fusion protein, recombinantly produced as a model ligand, exhibited characteristics of native Aβ. These features include the propensity to form aggregates or fibrils and an affinity for HSA with a dissociation constant (KD) of 0.91 μM. The HSA on the CA membrane showed concentration-dependent sequestration of GFP–Aβ in the 1–10-μM range. Moreover, it had a greater binding capacity than HSA immobilized on a commercial amine-binding plate. Results suggest that the covalent immobilization of HSA on the CA surface can be used as a potential platform for sequestering Aβ to alleviate AD. [Display omitted] •HSA was covalently immobilized onto a cellulose acetate membrane.•HSA immobilization was intensively verified by various analytic measures.•Functionality of HSA was evidenced by the presence of an esterase-like activity.•The binding of GFP-Aβ to HSA followed a concentration-dependent pattern with KD of 0.91 μM.