L. Grover (Birmingham, GB)
University of BirminghamPresenter Of 1 Presentation
16.2.6 - Suspended manufacture as a method to produce complex tissue interfaces
Abstract
Purpose
Hydrogels are in many ways the perfect materials to support tissue growth. They typically consist of a high volume of water (approximately 99%) and can form through relatively mild physical changes or chemical reactions. One of the major issues with hydrogels, however, is that they are typically relatively weak and are liquid up to the point of gelation. As a consequence, they are very challenging to fabricate in elaborate morphologies. We have addressed this problem by suspending hydrogel structures within a self-healing structured gel material that provides support to the hydrogel during the gelation process (see figure). In this abstract we report on how we have used this suspended manufacture process to produce 3D structures that consist of multiple cells types.
Methods and Materials
We created an osteochondral defect in a harvested tibial plateau. The defect was subsequently CT scanned and a CAD model of the defect was created. Cells were isolated from the cartilage and bone within the core and expanded before being deposited with a gellan reproduction of the defect (boney section was augmented with nanocrystalline HA) using the suspended manufacuring process with the CAD model. The plug was then reinserted into the defect and cultured for 28 days before characterisation with respect to physicochemical properties and the phenotype of the encapsulated cells.
Results
The plug that was manufactured using the suspended manfacturing process was robust and could be handled and reinserted into the defect without fragmentation. On retrieval from the gellan, the cells deposited within the cartilaginous region of the construct retained their chondrogenic phenotype (ACAN and Coll II expression) and those in the boney region maintained an osteoblastic phenotype (see figure).
Conclusion
We succsesfully demonstrated that suspended manufacture can create complex multicellular structures and that these structures could support maintenance of both osteoblastic and chondrogenic phenotypes in spatially defined regions.