title: [Structural and functional polarity of porcine hepatocyte cultured spheroids].
abstract: Hepatocytes are epithelial cells that show a complex polarity in vivo. However, hepatocytes isolated and cultured in vitro normally lose both their differentiated properties and polarity. Culturing hepatocyte spheroids seems to be the accurate approach to maintain tissue level of organization. The structural and functionalpolarities of pig liver spheroids were analyzed in this work. Swine liver cells were isolated and cultured as spheroids. Their metabolic activity was proved through the metabolism of diazepam, ammonium and synthesis of albumin. Several structural features show the presence of polarity in the cells inside the spheroids. Reticular and collagen fibers, as well as Ck19(+) cells forming duct-like structures were found. _eta and _-catenins and pancadherins were positive in different regions of the spheroids, mainly in the outer cell layers, which have cuboidal epithelia features. The scanning electron microscopy showed a tightly compacted architecture, with smooth surface. The transmission electron microscopy analysis showed bile canaliculi with microvilli, tight junctions, zonula adherens and desmosome-like junctions. Well-maintained cellular organelles, as mitochondria, nucleus, nucleolus, peroxisomes, endoplasmic reticulum, were seen in the spheroids. A complex inner bile canaliculi network was shown by using a fluorescent bile acid analogue incorporated and excreted by the spheroids. Furthermore, excretion of a normal pattern of bile acids was demonstrated. The morphology and functionality of the spheroids may provide an appropriate model for applications where the maintenance of liver-specific functions is crucial, as a bioartificial liver device.
authors.affiliation: Instituto de Ciencias Básicas y Medicina Experimental, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Alicia S
authors.initials: AS
authors.lastname: Lorenti
authors.forename: Alejandra M
authors.initials: AM
authors.lastname: Hidalgo
authors.forename: Mariana R
authors.initials: MR
authors.lastname: Barbich
authors.forename: José
authors.initials: J
authors.lastname: Torres
authors.forename: Juan
authors.initials: J
authors.lastname: Batalle
authors.forename: María F
authors.initials: MF
authors.lastname: Izaguirre
authors.forename: María Paula
authors.initials: MP
authors.lastname: Fiorucci
authors.forename: Víctor
authors.initials: V
authors.lastname: Casco
authors.forename: Adrián
authors.initials: A
authors.lastname: Gadano
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Argibay
mesh_terms: D000418:Albumins / Q000378:metabolism; D000818:Animals; D016764:Cell Polarity / Q000502:physiology*; D003975:Diazepam / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology* / Q000502:physiology; D018874:Spheroids, Cellular / Q000166:cytology* / Q000502:physiology; D013552:Swine; D014508:Urea / Q000378:metabolism
chemical_list: D000418:Albumins; D014508:Urea; D003975:Diazepam