title: A comparison of engineered urinary bladder and intestinal smooth muscle for urinary bladder wall replacement in a rabbit model.
abstract: OBJECTIVE
  The small intestine is the most common resource for bladder augmentation. Little is known whether intestinal smooth muscle cells (SMCs) may be engineered into bladder tissue. We investigated the phenotypic and functional characteristics of engineered bladder and intestinal SMCs as bladder wall replacement in a rabbit model.
  
  
  METHODS
  One month after an initial 70% partial cystectomy, 3 autoaugmentation surgeries were performed, including traditional autoaugmentation (TA, n = 6), TA using engineered bladder SMCs (TA + B, n = 6), and TA using intestinal SMCs (TA + I, n = 6). All were followed up by bladder volume measurement and retrieved on the first, third, and sixth month. The grafts and the native bladder wall were evaluated with immunocytochemistry and electrical field stimulation (EFS). Statistical analysis was performed using analysis of variance.
  
  
  RESULTS
  Both the TA + I and TA + B groups showed significant and similar bladder capacity increment in all time points. The engineered muscle cells demonstrated the typical "contraction-relaxation" response to supramaximal EFS. There were no statistical differences in both the TA + I and TA + B groups in contractility force.
  
  
  CONCLUSIONS
  Engineered SMCs derived from urinary bladder and small intestine could retain their phenotype after implantation in vivo. Both exhibited a similar degree of contractility to EFS. These results suggest that there are no phenotypic or functional differences between muscle cells obtained from the 2 different organs. Both have the potential to be engineered into normal bladder tissues.
authors.affiliation: Department of Pediatric Surgery, Chang-Gung Children's Hospital, School of Medicine, Chang-Gung University, Kweishan, Taoyuan 333, Taiwan. jylai@cgmh.org.tw
authors.forename: Jin-Yao
authors.initials: JY
authors.lastname: Lai
authors.forename: Pei-Yeh
authors.initials: PY
authors.lastname: Chang
authors.forename: Jer-Nan
authors.initials: JN
authors.lastname: Lin
mesh_terms: D000818:Animals; D007421:Intestine, Small / Q000637:transplantation; D008297:Male; D023421:Models, Animal; D009130:Muscle, Smooth / Q000637:transplantation; D032389:Myocytes, Smooth Muscle; D011817:Rabbits; D023822:Tissue Engineering; D001743:Urinary Bladder