M Cells Prefer Archaeosomes: An In Vitro/In Vivo Snapshot Upon Oral Gavage in Rats.

MARIA JOSE MORILLA; DIEGO MENGUAL; PABLO CABRAL; MIREL CABRERA; HENIA BALTER; MARIA VICTORIA DEFAIN TESOREIRO; LETICIA HIGA; DIANA I. RONCAGLIA,; EDER ROMERO

Current drug delivery

Bentham Science

Lugar: Oak Park; Año: 2011 vol. 8 p. 320 - 329

1567-2018

The archaeolipids (lipids extracted from archaebacterias) are non saponificable molecules that form self sealedmono or bilayers (archaeosomes-ARC). Different to liposomes with bilayers made of conventional glycerophospholipids,the bilayer of ARC posses a higher structural resistance to physico chemical and enzymatic degradation and surface hydrophobicity.In this work we have compared the binding capacity of ARC exclusively made of archaeols containing aminor fraction of sulphoglycophospholipids, with that of liposomes in gel phase on M-like cells in vitro. The biodistributionof the radiopharmaceutical 99mTc-DTPA loaded in ARC vs that of liposomes upon oral administration to Wistar ratswas also determined. The fluorescence of M-like cells upon 1 and 2h incubation with ARC loaded with the hydrophobicdye Rhodamine-PE (Rh-PE) and the hydrophilic dye pyranine (HPTS) dissolved in the aqueous space, was 4 folds higherthan upon incubation with equally labeled liposomes. Besides, 15% of Rh-PE and 13 % of HPTS from ARC and not from liposomes, were found in the bottom wells, a place that is equivalent to the basolateral pocket from M cells. This fact suggested the occurrence of transcytosis of ARC. Finally, 4 h upon oral administration, ARC were responsible for the 22.3 % (3.5 folds higher than liposomes) shuttling of 99mTc-DTPA to the blood circulation. This important amount of radioactive marker in blood could be a consequence of an extensive uptake of ARC by M cells in vivo, probably favored by their surface hydrophobicity. Taken together, these results suggested that ARC, proven their adjuvant capacity when administered by parenteral route and high biocompatibility, could be a suitable new type of nanoparticulate material that could be used as adjuvants by the oral route.