Background: Dialysis-related amyloidosis (DRA) is a severe complication in end-stage kidney disease (ESKD) patients undergoing long-term dialysis treatment, characterized by the deposition of β2-microglobulin-related amyloids (Aβ2M amyloid). To inhibit DRA progression, hexadecyl-immobilized cellulose bead (HICB) columns are employed to adsorb circulating β2-microglobulin (β2M). However, it is possible that the HICB also adsorbs other molecules involved in amyloidogenesis.
Methods: We enrolled 14 ESKD patients using HICB columns for DRA treatment; proteins were extracted from HICBs following treatment and identified using liquid chromatography-linked mass spectrometry. We measured the removal rate of these proteins and examined the effect of those molecules on Aβ2M amyloid fibril formation in vitro.
Results: We identified 200 proteins adsorbed by HICBs. Of these, 21 were also detected in the amyloid deposits in the carpal tunnels of patients with DRA. After passing through the HICB column and hemodialyzer, the serum levels of proteins such as β2M, lysozyme, angiogenin, complement factor D and matrix Gla protein were reduced. These proteins acted in the Aβ2M amyloid fibril formation.
Conclusions: HICBs adsorbed diverse proteins in ESKD patients with DRA, including those detected in amyloid lesions. Direct hemoperfusion utilizing HICBs may play a role in acting Aβ2M amyloidogenesis by reducing the amyloid-related proteins.
Keywords: Amyloid fibril formation; dialysis-related amyloidosis; hexadecyl-immobilized cellulose beads; mass spectrometry-based proteomic analysis; β2-microglobulin.