sepharose and Kidney-Failure--Chronic

Topics: Artificial Organs; Biological Products; Charcoal; Chromatography, Affinity; Dialysis; Extracorporeal Circulation; Humans; Kidney; Kidney Failure, Chronic; Liver; Liver Diseases; Perfusion; Renal Dialysis; Resins, Synthetic; Sepharose; Serum Albumin

The accumulation of advanced glycation end products (AGEs) has been reported to be a major contributor to chronic systemic inflammation. AGEs are not efficiently removed by hemodialysis or the kidney of a chronic kidney disease (CKD) patient. The goal of this study was to develop a receptor for AGEs (RAGE)-based bioadsorbent device that was capable of removing endogenous AGEs from human blood. The extracellular domain of RAGE was immobilized onto agarose beads to generate the bioadsorbent. The efficacy of AGE removal from saline, serum, and whole blood; biological effects of AGE reduction; and hemocompatibility and stability of the bioadsorbent were investigated. The bioadsorbent bound AGE-modified bovine serum albumin (AGE-BSA) with a binding capacity of 0.73 ± 0.07 mg AGE-BSA/mL bioadsorbent. The bioadsorbent significantly reduced the concentration of total AGEs in serum isolated from end-stage kidney disease patients by 57%. AGE removal resulted in a significant reduction of vascular cell adhesion molecule-1 expression in human endothelial cells and abolishment of osteoclast formation in osteoclast progenitor cells. A hollow fiber device loaded with bioadsorbent-reduced endogenous AGEs from recirculated blood to 36% of baseline levels with no significant changes in total protein or albumin concentration. The bioadsorbent maintained AGE-specific binding capacity after freeze-drying and storage for 1 year. This approach provides the foundation for further development of soluble RAGE-based extracorporeal therapies to selectively deplete serum AGEs from human blood and decrease inflammation in patients with diabetes and/or CKD.

Topics: Adsorption; Animals; Biomarkers; Cell Line; Down-Regulation; Equipment Design; Extracorporeal Circulation; Feasibility Studies; Glycation End Products, Advanced; Human Umbilical Vein Endothelial Cells; Humans; Kidney Failure, Chronic; Mice; Osteoclasts; Polymers; Protein Binding; Receptor for Advanced Glycation End Products; Receptors, Immunologic; Sepharose; Serum Albumin, Bovine; Sorption Detoxification; Sulfones; Time Factors; Vascular Cell Adhesion Molecule-1

Dialysis-related amyloidosis (DRA) is a devastating and costly condition that affects patients with end stage kidney disease. A key feature of DRA is the formation of amyloid fibrils, consisting primarily of beta2-microglobulin. Except for kidney transplantation, conventional kidney replacement therapies, which are based on nonspecific mechanisms, do not adequately address beta2-microglobulin removal. An antihuman beta2-microglobulin single-chain variable region antibody fragment (scFv) was developed to confer specificity to beta2-microglobulin removal during hemodialysis.. The scFv was immobilized onto agarose and characterized for beta2m binding capacity, thermal stability at 37 degrees C, regeneration capacity, storage conditions, and sterility.. The beta2-microglobulin binding capacity was 1.3 mg/ml scFv gel. The immunoadsorbent is thermally stable, can be regenerated, stored short-term in 20% ethanol, lyophilized for long-term storage, and withstand process conditions similar to that of a patient's hemodialysis therapy.. The results support further investigation of immobilized scFvs as a novel tool to remove beta2-microglobulin from blood.

Topics: Amyloidosis; beta 2-Microglobulin; Drug Stability; Extracorporeal Circulation; Humans; Immunoglobulin Variable Region; Immunosorbent Techniques; Kidney Failure, Chronic; Renal Dialysis; Sepharose; Sterilization