Application of Nanoparticles as Novel Adsorbents in Blood Purification Strategies.

BACKGROUND: Blood purification therapy for patients overloaded with metabolic toxins or drugs still needs improvement. Blood purification therapies, such as in hemodialysis or peritoneal dialysis can profit from a combined application with nanoparticles. SUMMARY: In this review, the published literature is analyzed with respect to nanomaterials that have been customized and functionalized as nano-adsorbents during blood purification therapy. Liposomes possess a distinct combined structure composed of a hydrophobic lipid bilayer and a hydrophilic core. The liposomes which have enzymes in their aqueous core or obtain specific surface modifications of the lipid bilayer can offer appreciated advantages. Preclinical and clinical experiments with such modified liposomes show that they are highly efficient and generally safe. They may serve as indirect and direct adsorption materials both in hemodialysis and peritoneal dialysis treatment for patients with renal or hepatic failure. Apart from dialysis, nanoparticles made of specially designed metal and activated carbon have also been utilized to enhance the removal of solutes during hemoadsorption. Results are a superior adsorption capacity and good hemocompatibility shown during the treatment of patients with toxication or end-stage renal disease. In summary, nanomaterials are promising tools for improving the treatment efficacy of organ failure or toxication. KEY MESSAGES: (i) The pH-transmembrane liposomes and enzyme-loaded liposomes are two representatives of liposomes with modified aqueous inner core which have been put into practice in dialysis. (ii) Unmodified or physiochemically modified liposomal bilayers are ideal binders for lipophilic protein-bound uremic toxins or cholestatic solutes, thus liposome-supported dialysis could become the next-generation hemodialysis treatment of artificial liver support system. (iii) Novel nano-based sorbents featuring large surface area, high adsorption capacity and decent biocompatibility have shown promise in the treatment of uremia, hyperbilirubinemia, intoxication, and sepsis. (vi) A major challenge of production lies in avoiding changes in physical and chemical properties induced by manufacturing and sterilizing procedures.

Combination Cyclophosphamide/Glucocorticoids Provide Better Tolerability and Outcomes versus Glucocorticoids Alone in Patients with Sjogren's Associated Chronic Interstitial Nephritis.

BACKGROUND: Steroid therapy has become an effective option for patients with primary Sjogren's syndrome with tubulointerstitial nephritis (TIN), while the use of cytotoxic agents is still debated. Our study aimed to compare the clinical outcomes of patients treated with cyclophosphamide (CTX) combined with glucocorticoids with those of patients treated with glucocorticoids alone. METHODS: All patients with primary Sjogren's syndrome with chronic TIN admitted to the Division of Nephrology, Ruijin Hospital, from January 1, 2002, to April 30, 2016, and treated with steroids alone or combined with CTX were included. The immunological prognosis, improvements of renal function, and acquired tubular defects of the patients were retrospectively compared between the 2 therapeutic groups. RESULTS: A total of 70 cases were included. Of these, 36 were diagnosed by renal biopsy. A total of 56 patients were treated with glucocorticoids alone, while 14 patients received glucocorticoids combined with CTX. There were no significant differences in clinical characteristics and laboratory parameters between the 2 therapeutic groups at baseline. Compared with patients in the steroid group, patients in the CTX group showed better estimated glomerular filtration rate (eGFR) improvement (21.35 ± 19.63 vs. 2.72 ± 19.11 mL/min/1.73 m2, p = 0.006) but a similar decline in immunoglobulin G (IgG; 450 [interquartile range, IQR 910] vs.176 [IQR 1,910] mg/dL, p = 0.93) at 12 months of follow-up. CTX therapy was associated with better eGFR improvement (ß = 12.96 [2.95-22.97]) even after adjusting for dry mouth, anti-Sjögren's-syndrome-related antigen A and anti-Sjögren's-syndrome-related antigen B positivity, hemoglobin, initial steroid dose, and baseline eGFR by linear regression analyses. Subgroup analyses revealed that the beneficial effects of CTX therapy on renal function were only observed in patients with baseline IgG ≥1,560 mg/dL or eGFR <90 mL/min/1.73 m2. The urine α1-microglobulin improvement was better in the CTX group than in the steroid group at 12 months of follow-up (ß = 1.29, 95% CI 0.56-2.02, p = 0.001). CONCLUSIONS: CTX therapy is suggested for primary Sjogren's syndrome patients with chronic TIN, especially those with higher IgG levels and abnormal renal function at baseline.

Polyethyleneimine-anchored liposomes as scavengers for improving the efficiency of protein-bound uremic toxin clearance during dialysis.

Protein-bound uremic toxins (PBUTs) are significant toxins that are closely related to the prognosis of chronic kidney disease. They cannot be effectively removed by conventional dialysis therapies due to their high albumin binding affinity. Our previous research revealed that cationic liposomes (i.e., polyethyleneimine [PEI]-decorated liposomes) could enhance the clearance of PBUTs via electrostatic interactions. However, the poor biocompatibility (hemolysis) restricted their applications in clinical dialysis treatment. Herein, we produced PEI-anchored, linoleic acid-decorated liposomes (CP-LA liposomes) via the conjugation of PEI to cholesterol chloroformate (Chol-PEI, CP), and linoleic acid (LA) was added to provide liposomal colloidal stability. The CP-LA liposomes outperformed the plain liposomes, demonstrating significantly higher PBUT binding rates and removal rates. In addition, in vitro dialysis simulation verified that the CP-LA liposomes had a better capacity for PBUT clearance than the plain liposomes, especially for PBUTs with a strong negative net charge. Hemolysis and cytotoxicity tests revealed that the biocompatibility of the CP-LA liposomes was better than that of the physically-decorated PEI-liposome. CP-LA liposomes possess great potential for PBUT clearance in clinical dialysis therapy.

Linoleic acid-modified liposomes for the removal of protein-bound toxins: An in vitro study.

INTRODUCTION: Protein-bound uremic toxins (PBUTs) and liver failure-related cholestatic solutes are associated with adverse outcomes in patients with chronic kidney disease (CKD) and liver failure, respectively, and are not easily removed by traditional dialysis therapies. We constructed linoleic acid-modified liposomes (LA-liposomes) as indirect adsorbent in the dialysate, and evaluated their effects on the clearance of the representative PBUTs and cholestatic solutes. METHODS: The LA-liposomes were prepared by the thin-film hydration method. The binding rates of liposomes and protein-bound solutes were detected by the ultrafiltration column. The in vitro dialysis experiments were performed using both non-current and current devices to assay the clearing efficiency of the dialysate supported by LA-liposomes. RESULTS: The LA-liposomes exhibited good binding properties to the PBUTs, bilirubin and bile acids. The LA-liposome dialysate showed higher solute reduction rates of the representative PBUTs and cholestatic solutes than the traditional dialysate or dialysate supported by the unmodified plain liposomes. Also, albumin binding of the PBUTs was significantly inhibited by the addition of linoleic acid (LA), and the removal efficiency of PBUTs was greatly enhanced by the combination of indirect adsorbent LA-liposomes and LA as the competitive displacer. CONCLUSION: LA-liposomes were efficient in the clearance of the representative PBUTs and liver failure-related solutes. Moreover, the combination of indirect adsorbent LA-liposomes and competitive displacer suggested a potential application for the extremely highly-bound solutes.

Layer-by-layer assembly of polyelectrolyte and graphene oxide for open-tubular capillary electrochromatography.

In this paper, open-tubular capillary column coated with graphene oxide (GO) was prepared through ionic adsorption of negatively charged GO nanosheets onto the capillary wall pre-modified with positively charged poly(diallydimethylammonium chloride) (PDDA). Thus prepared coating was very stable and could endure over 200 separations. The electroosmotic flow (EOF) characteristics of bare fused silica capillary column, PDDA coated column, and GO-PDDA coated column (GO-PDDA@column) were investigated by varying the percentage of methanol in buffer and the buffer pH value. The run-to-run, day-to-day, and column-to-column reproducibilities of EOF on GO-PDDA@column were satisfying with relative standard deviation values of less than 2% in all cases. The stationary phase displays a characteristic reversed-phase behavior. The GO-PDDA@column was also used to separate proteins in egg white. Both basic and acidic proteins were separated in a single run.