Ansari Tahera¹, David Lloyd², Sandra Shurey¹, Paul Sibbons¹, Simon Gabe²

¹NPIMR, London, United Kingdom; ²Department of Gastroentereology, St Marks, London, United Kingdom

Background: Attempts to lengthen the intestine by interposition of artificial tubular scaffolds juxtaposed between healthy tissue has shown limited success, mainly because neo-intestine rarely survives for long since there is little associated vasculature. To date, synthetic scaffolds or hybrids have been the mainstay of tissue engineered neo-intestinal tissue. Biologically derived de-cellularised scaffolds although prominent in other fields have not been utilised for small or large bowel tissue engineering. We combined a biologically derived de-cellularised scaffold together with organoid units to produce differentiated neointestinal mucosa.

Methods: De-cellularised rat colon was produced using a combination of enzymes and detergents (see figure 1). This was seeded with intestinal organoid units and subcutaneously implanted for 2, 4 and 6 weeks in Lewis rats. In separate animals, a 1.5cm length of de-cellularised colon was interposed between healthy jejunum (n=6 for 4 and 8 weeks). All tissue was assessed histologically.

Results: Using de-cellularised rat bowel it was possible to produce neo-intestinal mucosa consisting of all four intestinal cell lineages (see figure 2). After 6 weeks implantation the following cell lineages were identified: Paneth cells, enteroendocrine cell and goblet cells containing mucin in the neomucosal layer. In addition, multiple blood and lymphatic vessels and elongated smooth muscle-like cells were visible in the submucosal layer. Scaffold interposition was only successful in 2/6 animals due to the fragility of the scaffold and consequent adhesions.

Conclusion: Using seeded de-cellularised tissue it is possible to produce differentiated biocompatible tissue. A de-cellularised scaffold retains the natural, 3D structure of the native tissue which may significantly influence cellular proliferation and differentiation and therefore offers a biological advantage over a synthetic scaffold. To take this model a step closer to clinical application, we are currently investigating the use of de-cellularised porcine bowel as a potential scaffold.