On the Use of Hydrogels in Cell Encapsulation and Tissue Engineering Systems

Regenerative medicine requires the coordinated rebuilding of tissue and preservation of normal physiologic function. Cellular therapy incorporating tissue engineering principals has been among the most effective therapies, due to specific interactions between materials, cells, factors, and ligands that have been delineated over the last 5 decades. The current generation of these modalities incorporates the ability to control integration in vivo in a time- and space-dependent fashion. Hydrogels have been used as biofunctional vehicles for the introduction of these cell-based systems, and new techniques allow for the control of cell adhesion, proliferation, differentiation, and other biologic functions in vivo. With these more robust methods in place, and the ability to scale up and manufacture clinical materials, additional innovations have evolved that allow for ectopic or orthotopic administration of cellular therapies to treat disorders that have previously seen limited therapeutic promise due to inability to provide time-matched therapy. As such, critical discoveries have gained a unique niche portfolio of novel patents, accounting for a large portion of those newly filed in the field of biotechnology. These include the novel hydrogel compositions engineered by David Mooney and his colleagues, various tissue bulking and reconstructive applications invented by Hubbell and others, and other important patents in this field. The inventions described here provide insight into important aspects of this overall movement, and demonstrate significant immediate clinical utility in a variety of indications.