In vitro Inhibition of Fungal Activity by Macrophage‐Mediated Sequestration and Release of Encapsulated Amphotericin B Nanosupension in Red Blood Cells

Abstract

The efficacy of antifungal treatment has been diminished by the biodistribution limitations of amphotericin B (AmB) due to its pharmacological profile, as well as the severe side effects it causes. A cellular drug-delivery system, which incorporates human erythrocytes (RBCs) loaded with an AmB nanosuspension (AmB-NS), is developed in order to improve antifungal treatment. AmB-NS encapsulation in RBCs is achieved by using hypotonic hemolysis, leading to intracellular AmB amounts of 3.81 +/- 0.47 pg RBC(-1) and an entrapment efficacy of 15-18%. Upon phagocytosis of AmB-NS-RBCs, leukocytes show a slow AmB release over ten days, and no alteration in cell viability. This results in an immediate, permanent inhibition of intra- and extracellular fungal activity. AmB-NS-RBC-leukocyte-mediated delivery of AmB is efficient in amounts 1000 times lower than the toxic dose. This drug-delivery method is effective for the transport of water-insoluble substances, such as AmB, and this warrants consideration for further testing.

Biomembranes from slaughterhouse blood erythrocytes as prolonged release systems for dexamethasone sodium phosphate

“…The results obtained for DexP loaded porcine erythrocyte ghosts were comparable (in the same range) to the results published for loading different active compounds (drugs, enzymes, proteins, polysaccharides, and DNA) in human erythrocytes ghosts by hypoosmotic procedures . Lower EE attained in the case of bovine erythrocyte ghosts were in the same range as reported by Kim and co‐workers for AS‐ODN encapsulated in human erythrocyte ghosts by loading procedure where hypotonic and isotonic phosphate buffers were employed.…”

“…The results obtained for DexP loaded porcine erythrocyte ghosts were comparable (in the same range) to the results published for loading different active compounds (drugs, enzymes, proteins, polysaccharides, and DNA) in human erythrocytes ghosts by hypoosmotic procedures. 27,36,[38][39][40] Lower EE attained in the case of bovine erythrocyte ghosts were in the same range as reported by Kim and co-workers 41 for AS-ODN encapsulated in human erythrocyte ghosts by loading procedure where hypotonic and isotonic phosphate buffers were employed. Contrary to this, Sternberg et al 42 reported approximately 97% EE of fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) in hemoglobin free human erythrocyte ghosts, where also phosphate buffers were applied in the loading procedure.…”

Preparation and in-vitro characterization of tramadol-loaded carrier erythrocytes for long-term intravenous delivery

“…We reached 95% entrapment efficiency for tramadol in our laboratory. This was remarkable compared with the results published for amphotericin B (15–18%), methotrexate (60%), prednisolone (85.4%) and, obviously, for large molecular weight drugs such as bovine serum albumin (59.8%), β ‐glucocerebrosidase (40–50%), and insulin (5%), upon loading in erythrocytes using the same method [13,48–52] …”

Cell-mediated drug delivery

“…To this end, erythrocytes were suggested as delivery vehicles for antifungal agent, amphotericin B (AmB). In order to avoid toxic effects and achieve efficient drug loading, AmB was encapsulated in nanosuspension (AmB-NS) by high-pressure homogenization 106. AmB-NS was loaded into RBC by using hypotonic hemolysis, leading to intracellular AmB amounts of 3.81 +/- 0.47 pg RBC -1 and an entrapment efficacy of 15-18%.…”