Histochemistry and Cell Biology

, Volume 150, Issue 5, pp 567–574 | Cite as

Reuse of bladder mucosa explants provides a long lasting source of urothelial cells for the establishment of differentiated urothelia

  • Urška Dragin Jerman
  • Mateja Erdani KreftEmail author
Short Communication


Organ explant cultures are well-established in vitro models that are used to study normal cell biological and regeneration processes as well as carcinogenesis. Primary urothelial cultures from bladder mucosa explants are highly differentiated and are thus broadly used as in vitro experimental equivalents of native urothelial tissue. Since experiments on differentiated urothelial cultures from bladder mucosa explants currently allow only a single use of explants, establishment of sufficient quantities of cultures requires large numbers of sacrificed animals. There is thus a great need for a cheaper approach with less ethical dilemmas. Herein, we demonstrate that mouse bladder mucosa explants can be reused. Reused explants produce outgrowths with highly differentiated urothelia, just like primary explants. Even after being recycled ten times, urothelial outgrowths have the supramolecular and ultrastructural features that are comparable to the native urothelium. Ten times reused explants produce superficial urothelial cells that express uroplakins in the apical plasma membrane, claudin-8 in the tight junctions, and have a subapical network of cytokeratin 20. Basal urothelial cells in urothelial outgrowths of ten times reused explants express p63 which indicates that these urothelial outgrowths have a persistent proliferative capacity. Using our approach, one can perform experiments that were previously not feasible due to low quantities of donor tissue. The method also offers opportunity for effective use of scarce healthy human urothelial tissue.


Explant cultures Urothelial model Donor tissue Urinary bladder Microscopy Immunofluorescence 



The authors acknowledge the financial support from the Slovenian Research Agency (research core Funding No. P3-0108, Young-researcher funding, and Project No. J3-7494). Thanks also to Sanja Čabraja, Nada Pavlica Dubarič, Linda Štrus, and Sabina Železnik for technical assistance.


This study was funded by Slovenian Research Agency (research core Funding No. P3-0108, Young-researcher funding, and Project No. J3-7494).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute of Cell Biology, Faculty of MedicineUniversity of LjubljanaLjubljanaSlovenia

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