But John Comley, Ph.D., managing director of HTStec, an independent market research consultancy focused on assisting clients delivering novel enabling platform technologies, wrote in a 2010 report that based on vendor descriptions, “One might conclude that 3D cell culture was a done deal and tissue generation is readily achievable. However, HTStec’s survey uncovered many problems and unmet needs.”
Among these were poor reproducibility between batches of biomimetic scaffolds, 3D matrices with too many components, and limited ability to scale up or down a single 3D format. Further, he noted, users reported that post-culturing processing/cell extraction proved difficult to handle and that proven automated solutions with a higher throughput were required. In particular, he noted, there was room for improvement with more physiological substrates, and greater stability in long-term experiments was needed.
He added that in 2010 at least, the state-of-the-art “seems some way off from providing fully validated or robust 3D culture solutions, and the field is clearly open to major improvements at this point in time.” 3D remains challenged as comparable results from different culture systems continue to plague investigators.
Investigators at the department of engineering science, National Cheng Kung University, Taiwan, reported that they had developed a high-throughput perfusion, 3D microfluidic cell and described the development of an integrated system aimed at providing a “user-friendly cell culture tool” for biologists to perform assays, “but also to enable them to obtain precise data.”
Noting that while microfluidic cell culture systems are versatile tools for cellular assays, their use has yet to set in motion an evolutionary shift away from conventional cell culture methods, SB Huang and colleagues commented that the “situation is mainly due to technical hurdles.” The operational barriers to the end-users, the lack of compatible detection schemes capable of reading out the results of a microfluidic-based cellular assay, and the lack of fundamental data to bridge the gap between microfluidic and conventional cell culture models all pose issues to the use of such systems, they said.
Technical features of their culture system included integration of a heater chip based on transparent indium tin oxide glass that provides stable thermal conditions for cell culturing. The platform also features a microscale 3D culture sample loading scheme that is both efficient and precise, a nonmechanical pneumatically driven multiplex medium perfusion mechanism, and a microplate reader-compatible waste medium collector array for the subsequent high-throughput bioassays.
To determine the effects of cell culture models on cellular proliferation, and the results of chemosensitivity assays, the investigators compared their data with that obtained using three conventional cell culture models. They found that the nature of the cell culture format could lead to different evaluation outcomes, cautioning that when establishing a cell culture model for in vitro cell-based assays, it might be necessary to investigate the fundamental physiological variations of the cultured cells in different culture systems to avoid any misinterpretation of data.
But overall, they say, their integrated microfluidic cell culture system overcame several technical hurdles associated with the practical application of microfluidic cell culture systems, and obtained fundamental information to reconcile differences found with data acquired using conventional methods.