Removal of intact β2-microglobulin at neutral ph by using seed-conjugated polymer beads prepared with β2-microglobulin-derived peptide (58-67).

Removal of beta 2-microglobulin (beta 2M) from the blood of patients suffering from kidney dysfunction is crucial to protect those individuals from getting the diseased state of dialysis-related amyloidosis. By harnessing the nucleation-dependent fibrillation process of amyloidogenesis, a beta 2M removal strategy has been proposed by preparing seed-conjugated polymer beads and assimilating soluble beta 2M to the fibrils on the surface at neutral pH. A novel peptide segment of beta 2M ranging from residue 58 to residue 67 (Lys-Asp-Trp-Ser-Phe-Tyr-Leu-Leu-Tyr-Tyr), which was capable of being fibrillated at neutral pH was isolated. Charge interaction between the positive N-terminal lysine and the negative C-terminal a-carboxylic group was demonstrated to be critical for the molecular self-assembly leading to the peptide fibril formation by favoring b-sheet conformation. Because the peptide fibrils were successful to seed intact beta 2M at neutral pH, the fibrils were immobilized on polymer beads of HiCore resins, and the resulting seed-conjugated beads were used to accrete intact beta 2M in the form of fibrils elongated on the bead surface. Its efficiency of the beta 2M removal was improved by placing the seed-immobilized beads in the middle of a continuous flow of the beta 2M-containing solution as practiced in the blood circulation during the hemodialysis. Therefore, this b2M removal system is suggested to exhibit high specificity, high binding capacity, and costeffectiveness appropriate for eventual clinical application to remove beta 2M from the blood of renal failure patients. (C) 2011 American Institute of Chemical Engineers Biotechnol. Prog., 27: 521-529, 2011