High Molecular Weight Blood group A Trisaccharide-Polyacrylamide Glycoconjugates As Synthetic Blood Group A Antigens For Anti-A Antibody Removal Devices

摘要

Specific immunoadsorption of blood group antibodies by synthetic antigens immobilized on support matrices in the peri-transplantation period provides a promising solution to hyperacute rejection risk following ABO-incompatible transplantation. In this study, we investigated binding interactions between anti-A antibodies and synthetic blood group A trisaccharide conjugated with polyacrylamide of different molecular weights (30 and 1000 kDa). The glycopolymers were equipped with biotin tags and deposited on streptavidin-coated sensor chips. The affinity and kinetics of anti-A antibodies binding to glycoconjugates were studied using surface plasmon resonance (SPR). The high molecular weight conjugate (Atri-PAA¹⁰⁰⁰-biotin) enhanced antibody binding capacity by two to three fold compared to the low molecular weight conjugate (Atri-PAA³⁰-biotin), whereas varying the carbohydrate content in Atri-PAA¹⁰⁰⁰-biotin (20 mol% or 50 mol%) did not affect antibody binding capacity of the glycoconjugate. The obtained results suggest that immunoadsorption devices, especially hollow fiber-based antibody filters which are limited in available surface area for antigen immobilization, may greatly benefit from the new synthetic high molecular weight polyacrylamide glycoconjugates.