Developing “Off the Shelf” Pancreases for Diabetic Patients Using Bacterial and Kombucha Tea Waste

Abstract

The advent of tissue and organ engineering provides long-term treatment for conditions previously considered chronic and untreatable. Through advances in the field of tissue engineering, patients have the potential to receive synthetic replacements of damaged tissues and cellular grafts. Scaffolds, based in either synthetic or natural polymers, are fundamental to tissue engineering approaches because they provide a structure that mimics the native environment which facilitates cellular differentiation, organization, and functionality. However, current protocols for creating scaffolds remain complex and difficult to translate to the clinic. Our investigation aimed to provide potential solutions to fundamental issues associated with islet cell transplantation, a possible cure for type 1 diabetes. In this study, we used bacterial cellulose as the polymer to create scaffolds. We modulated the structural characteristics of the bacterial cellulose to aid cellular infiltration. After processing, scanning electron micrographs of the scaffolds showed that a favorable blood vessel morphology was maintained and an open pore geometry was obtained. We effectively manipulated the porosity of the scaffold by altering agarose concentrations. The 0.5% agarose-cellulose composite group had an average pore area of 20,000 µm2, which permitted the establishment of regionalized cells islands. Notably, the popular fermented tea drink, kombucha, produces bacterial cellulose as a waste product. Kombucha is made using a symbiotic culture of bacteria and yeast (SCOBY). Normally, SCOBYs are simply discarded after the fermentation process is complete, but could have untapped potential as a platform for tissue engineering and transplantation procedures. To verify that bacterial cellulose can be used as a biomimetic platform, INS-1 cells (an insulin-secreting beta cell-derived line) were seeded in the bacterial cellulose scaffold. We observed morphological changes, such as cytoplasmic extensions and clustering, suggesting reestablishment of functional cell islands. Hence, the results of our experiments suggested that bacterial cellulose is a cost-effective scaffolding platform that can be used to house islet cells as a promising tool in islet cell transplantation, a possible cure for diabetes.