ABSTRACT
PURPOSE: This study demonstrates the nasal administration (NA) of nanoemulsions complexed with the plasmid encoding for IDUA protein (pIDUA) as an attempt to reach the brain aiming at MPS I gene therapy. METHODS: Formulations composed of DOPE, DOTAP, MCT (NE), and DSPE-PEG (NE-PEG) were prepared by high-pressure homogenization, and assessed in vitro on human fibroblasts from MPS I patients and in vivo on MPS I mice for IDUA production and gene expression. RESULTS: The physicochemical results showed that the presence of DSPE-PEG in the formulations led to smaller and more stable droplets even when submitted to dilution in simulated nasal medium (SNM). In vitro assays showed that pIDUA/NE-PEG complexes were internalized by cells, and led to a 5% significant increase in IDUA activity, besides promoting a two-fold increase in IDUA expression. The NA of pIDUA/NE-PEG complexes to MPS I mice demonstrated the ability to reach the brain, promoting increased IDUA activity and expression in this tissue, as well as in kidney and spleen tissues after treatment. An increase in serum IL-6 was observed after treatment, although with no signs of tissue inflammatory infiltrate according to histopathology and CD68 assessments. CONCLUSIONS: These findings demonstrated that pIDUA/NE-PEG complexes could efficiently increase IDUA activity in vitro and in vivo after NA, and represent a potential treatment for the neurological impairment present in MPS I patients.
Subject(s)
Mucopolysaccharidosis I/therapy , Nanoparticles/chemistry , Nucleic Acids/administration & dosage , Administration, Intranasal , Animals , Brain/metabolism , Cations , Cell Survival/drug effects , Emulsions , Fatty Acids, Monounsaturated/chemistry , Fibroblasts/pathology , Gene Transfer Techniques , Genetic Therapy , Genetic Vectors , Humans , Iduronidase/biosynthesis , Iduronidase/genetics , Mice , Mice, Inbred C57BL , Mucopolysaccharidosis I/genetics , Mucopolysaccharidosis I/pathology , Particle Size , Phosphatidylethanolamines/chemistry , Polyethylene Glycols/chemistry , Quaternary Ammonium Compounds/chemistry , Spleen/metabolism , TransfectionABSTRACT
Cell encapsulation, although a promising strategy to deliver therapeutic products, is hampered by immune response against biomaterials. The aim of this article is to assess the effect of prednisolone on enzyme release by microencapsulated cells implanted in vivo. Recombinant cells encapsulated were implanted in the peritoneum of wild-type mice and mucopolysaccharidosis (MPS) I mice, with or without prednisolone. Later, microcapsules were recovered for histological and enzyme analysis. Blood was collected from MPS I mice. All animals receiving prednisolone had a smaller inflammatory infiltrate. In vitro, prednisolone increased the amount of enzyme released from the recovered capsules, but this was not accompanied by an increase in the amount of circulating enzyme in vivo after 15 days. However, in 7 days, prednisolone significantly increased the amount of enzyme detected in the serum. Although prednisolone improved enzyme release in vitro and in vivo after 7 days, it was unable to maintain this effect for a longer period.