Bioengineering of the digestive tract: approaching the clinic.

The field of regenerative medicine is developing technologies that, in the near future, will offer alternative approaches to either cure diseases affecting the gastrointestinal tract or slow their progression by leveraging the intrinsic ability of our tissues and organs to repair after damage. This article will succinctly illustrate the three technologies that are closer to clinical translation-namely, human intestinal organoids, sphincter bioengineering and decellularization, whereby the cellular compartment of a given segment of the digestive tract is removed to obtain a scaffold consisting of the extracellular matrix. The latter will be used as a template for the regeneration of a functional organ, whereby the newly generated cellular compartment will be obtained from the patient's own cells. Although clinical application of this technology is approaching, product development challenges are being tackled to warrant safety and efficacy.

Extracellular matrix-based hydrogels obtained from human tissues: a work still in progress.

PURPOSE OF REVIEW: The current review summarizes contemporary decellularization and hydrogel manufacturing strategies in the field of tissue engineering and regenerative medicine. RECENT FINDINGS: Decellularized extracellular matrix (ECM) bioscaffolds are a valuable biomaterial that can be purposed into various forms of synthetic tissues such as hydrogels. ECM-based hydrogels can be of animal or human origin. The use of human tissues as a source for ECM hydrogels in the clinical setting is still in its infancy and current literature is scant and anecdotal, resulting in inconclusive results. SUMMARY: Thus far the methods used to obtain hydrogels from human tissues remains a work in progress. Gelation, the most complex technique in obtaining hydrogels, is challenging due to remarkable heterogeneity of the tissues secondary to interindividual variability. Age, sex, ethnicity, and preexisting conditions are factors that dramatically undermine the technical feasibility of the gelation process. This is contrasted with animals whose well defined anatomical and histological characteristics have been selectively bred for the goal of manufacturing hydrogels.