title: Injection of porous polycaprolactone beads containing autologous myoblasts in a dog model of fecal incontinence.
abstract: OBJECTIVE
  Few studies have examined whether bioengineering can improve fecal incontinence. This study designed to determine whether injection of porous polycaprolactone beads containing autologous myoblasts improves sphincter function in a dog model of fecal incontinence.
  
  
  METHODS
  The anal sphincter of dogs was injured and the dogs were observed without and with (n = 5) the injection of porous polycaprolactone beads containing autologous myoblasts into the site of injury. Autologous myoblasts purified from the gastrocnemius muscles were transferred to the beads. Compound muscle action potentials (CMAP) of the pudendal nerve, anal sphincter pressure, and histopathology were determined 3 months after treatment.
  
  
  RESULTS
  The amplitudes of the CMAP in the injured sphincter were significantly lower than those measured before injury (1.22 mV vs. 3.00 mV, P = 0.04). The amplitudes were not different between dogs with and without the injection of autologous myoblast beads (P = 0.49). Resting and squeezing pressures were higher in dogs treated with autologous myoblast beads (2.00 mmHg vs. 1.80 mmHg; 6.13 mmHg vs. 4.02 mmHg), although these differences were not significant in analyses of covariance adjusted for baseline values. The injection site was stained for smooth muscle actin, but showed evidence of foreign body inflammatory reactions.
  
  
  CONCLUSIONS
  This was the first study to examine whether bioengineering could improve fecal incontinence. Although the results did not show definite evidence that injection of autologous myoblast beads improves sphincter function, we found that the dog model was suitable and reliable for studying the effects of a potential treatment modality for fecal incontinence.
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Sung-Bum
authors.initials: SB
authors.lastname: Kang
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Lee
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Lim
authors.forename: Se Heang
authors.initials: SH
authors.lastname: Oh
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Kim
authors.forename: Sa-Min
authors.initials: SM
authors.lastname: Hong
authors.forename: Je-Ho
authors.initials: JH
authors.lastname: Jang
authors.forename: Jeong-Eun
authors.initials: JE
authors.lastname: Cho
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Lee
keywords: Bioengineering; Dogs; Fecal incontinence; Myoblasts