Diverse Tissue Engineering Applications and Automated Cell Harvesting
George Joseph Christ (University of Virginia) began with an overview of the importance of treating volumetric muscle loss injuries.
He presented data supporting the application of tissue-engineered muscle repair (TEMR) constructs in animal models and tissue engineering to repair volumetric muscle loss injuries (face and hand) and the use of sheet-based tissue-engineered medical products (TEMPs) for muscle repair.
He presented data showing the benefits of adding seeding cellular material on an extracellular matrix scaffold (2-cm square area), comparing TEMR (with cells) results (e.g., volume quality, composition, vascularization, contractile force) with those of applying bladder acellular matrix (BAM) alone.
Christ reviewed his group’s TEMR implant process and manual engineering process, including taking a biopsy from a patient, expanding progenitor cells, matrix seeding (manually), tissue stretching, and preconditioning of skeletal muscle constructs in a bioreactor for in vitro maturation.
“The idea is that we are not implanting mature muscle. We are implanting myoblasts and myotubes (mainly myoblasts) to create a regenerative template, which enhances the microenvironment for tissue repair that normally would not exist in adult mammals to improve tissue repair.”
Christ compared the traditional manual TEMR creation process with automated bioprinting.
“We envision an automated bioprinting method whereby we can take the same construct, put it in a holder in the same bioreactor used for the TEMR approach, and bioprinting instead of manually seeding at a higher initial cell density with fewer cells in a rapid process, and then placing the system back into the bioreactor.”
He summarized the TEMR approach as being a “hybrid” biofabrication process between bioprinting and cell sheets and showed a process (and challenges) for bioprinting tissue-engineered medicinal products (TEMPs).
Sonia Bulsara (Cytiva) presented the company’s technology for each stage of a cell therapy workflow.
She focused on capabilities and applications of the Sepax C and Sefia cell processing and isolation instruments.
The former is composed of the hardware, protocol software, and cell processing kit.
The automated system is closed for compliance to good manufacturing practice (GMP) applications. The Sepax instrument uses centrifugation for cell separation, as specified by a protocol.
The optical detection to sense the transition of layers between the cells that have been separated so that the cells can be pulled to the appropriate bag.
Applications include harvesting of mesenchymal stems cells (MSCs) and T cells.
The Sefia instrument was developed to address scale up to handle larger volumes (up to 10 L) and higher capacities.
It includes sensors for weight, temperature and enables eight fluid pathways. The instrument can be implemented in continuous flow processes.
Applications for the Sefia system include isolation in upstream manufacturing workflow (PremierCell protocol) and automated cell harvest (FlexCell protocol).
