Univ. of Luisville
Bioprinted islet spheroids containing adipose-derived stromal vascular fraction cells using a 3D bioprinting technology improves islet integrity and function
Gopalakrishnan Loganathan1, A.N. Balamurugan1, Micheal Hughes1, Benjamin Tweed1, Leigh Kleinert1, Nicholas George1, Stuart K Williams1.
1Islet Cell Laboratory, Department of Surgery, Cardiovascular Innovation Institute,, University of Louisville, Louisville, KY, United States
Background: Adipose-derived stromal vascular fraction cells (SVF) are known to create microvascular networks and release angiogenic tropic factors (eg., VEGF, bFGF, HGF, and IGF). In this study, we bioprinted islet spheroids containing SVF cells utilizing direct write three-dimensional bioprinting technology (3D printing) to improve islet function. The spheroids keep the co-cultured cells in close proximity and in a fixed location for ideal cellular interactions and also provide 3D matrix support.
Research Design and Method: Transgenic green fluorescent protein (GFP) adult male Sprague Dawley rat islets and adipose-derived SVF cells from wild type rats were isolated. Isolated islets and SVF cells are then mixed together or individually suspended in the final 3% alginate-3mg/ml collagen solution. The suspended cells in the solution are then printed as spheroids in 1.1% CaCl2 using a 3D printing technology. Bioprinted islet/SVF spheroids were assessed for islet cell integrity, viability and insulin secretory capability.
Results: Our results showed that uniform size (1000-1500μm) of islet/SVF cell spheroids could be successfully prepared (Figure 1). Islet morphology and integrity was well maintained in spheroids even after one month in culture due to 3D matrix and SVF support. However, in naked (cultured alone without gel) control islets a slow disintegrated process occurs after one week culture. Basal insulin secretion into the culture medium and glucose stimulated insulin release were comparable to control islets (Figure 2). Bioprinted islet viability (>90%) was maintained long term.
Conclusions: We have established a method to use a novel bioprinting system to create cellular organoids. We have observed that multipotent SVF cells have the capability to induce intra-islet endothelial cell growth and peri-islet capillary formation. The combination of the islet and SVF cells in a 3D matrix extended the viability of the islets and promoted intra islet capillary growth. This data will be carried forward to develop an islet organoid printing system that will simultaneously print islets and a prevascularized construct in a spheroid configuration ready for implantation.
Robert M Reed.
 Stuart K. Williams, et al., Biores Open Access. 2013 December 1; 2(6): 448–454.
11:00 - 12:30
|Alternative Sources of Beta Cells: Xenoislet, Stem Cells, Tissue Engineering||Bioprinted islet spheroids containing adipose-derived stromal vascular fraction cells using a 3D bioprinting technology improves islet integrity and function||Room 110|