Assessment of stability, toxicity and immunogenicity of new polymeric nanoreactors for use in enzyme replacement therapy of MNGIE.
The lack of a crucial metabolic enzyme can lead to accumulating substrate concentrations in the bloodstream and severe human enzyme deficiency diseases. Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE) is such a fatal genetic disorder, caused by a thymidine phosphorylase deficiency. Enzyme replacement therapy is a strategy where the deficient enzyme is administered intravenously in order to decrease the toxic substrate concentrations. Such a therapy is however not very efficient due to the fast elimination of the native enzyme from the circulation. In this study we evaluate the potential of using polymeric enzyme-loaded nanoparticles to improve the delivery of therapeutic enzymes. We constructed new 200-nanometer PMOXA-PDMS-PMOXA polymeric nanoparticles that encapsulate the enzyme thymidine phosphorylase. These particles are permeabilised for substrates and products by the reconstitution of the nucleoside-specific porin Tsx in their polymeric wall. We show that the obtained 'nanoreactors' are enzymatically active and stable in blood serum at 37 degrees C. Moreover, they do not provoke cytotoxicity when incubated with hepatocytes for 4 days, nor do they induce a macrophage-mediated inflammatory response ex vivo and in vivo. All data highlight the potential of such nanoreactors for their application in enzyme replacement therapy of MNGIE.
Structural Biology Brussels, Vrije Universiteit Brussel (VUB), 1050 Brussels (Elsene), Belgium. Caroline.De.Vocht@vub.ac.be
Caroline
C
De Vocht
An
A
Ranquin
Ronnie
R
Willaert
Jo A
JA
Van Ginderachter
Tamara
T
Vanhaecke
Vera
V
Rogiers
Wim
W
Versées
Patrick
P
Van Gelder
Jan
J
Steyaert
D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry* / Q000633:toxicity*; D010080:Oxazoles / Q000008:administration & dosage / Q000737:chemistry* / Q000633:toxicity*; D010316:Particle Size; D011108:Polymers / Q000008:administration & dosage / Q000737:chemistry* / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011991:Receptors, Virus / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D013939:Thymidine Phosphorylase / Q000008:administration & dosage* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D010080:Oxazoles; D011108:Polymers; D011991:Receptors, Virus; C542789:poly(2-methyl oxazoline)-block polydimethylsiloxane-block-poly(2-methyl oxazoline); C066743:Tsx protein, E coli; D007770:L-Lactate Dehydrogenase; D013939:Thymidine Phosphorylase