Abstract Book - 26th ESPU Congress, Joint Meeting with ICCS + SPU + AAP/SOU + AAPU + SFU

BSP-15

(P)

A MINCED TISSUE MODEL FOR TISSUE EXPANSION WITH MINCED AUTOLOGOUS

TISSUE FOR UROGICAL RECONSTRUCTIVE SURGERY

Gisela REINFELDT ENGBERG

, Clara IBEL CHAMORRO

and Magdalena FOSSUM

1) Karolinska Institute, Womens and childrens health, Stockholm, SWEDEN - 2) Karolinska Institute, Womes and

childrens health, Stockholm, SWEDEN

PURPOSE

In previous studies we created a urinary conduit in an in vivo animal model for bladder emptying with minced

autologous urothelium. To further develop the conduit, we compared cell regeneration and tissue expansion with

biografts of urothelium alone or urothelium together with detrusor muscle in in vitro and in vivo studies.

MATERIAL AND METHODS

Porcine minced tissue, 0.3x0.3 mm, of urothelium only or urothelium and detrusor muscle was seeded by plastic

compression in collagen-biografts for in vitro cultivation of 2-3 weeks. In vivo, we transplanted the same type of cells on

3D cylinder moulds into the subcutaneous fat of the pig abdominal wall in a one-step procedure for harvesting the

urinary bladder tissue and transplanting back, terminating after 4-5 weeks. 6 moulds received urothelium only and 6

received urothelium and detrusor muscle. The expansion rate was 1:3. Outcome was measured by histology of the

luminal surface and underlying tissue. Shams without minced were used as controls.

RESULTS

In vitro cultivation demonstrated a single cell-layer of urothelium after 2 weeks. No other cells could be detected. There

was no morphological difference between samples when comparing urothelium only to urothelium with detrusor. In in

vivo transplantation studies, minced urothelium only demonstrated a multi-layered transitional urothelium but not with

transplanting minced urothelium together with detrusor muscle nor in shams. These samples demonstrated that

angiogeneses was greater with higher grade of inflammation.

CONCLUSIONS

Minced tissue models can be used to expand urothelium. It is easy and fast to perform in vitro or in vivo. In vivo, there

was no improvement on urothelial outcome when seeding together with detrusor muscle.