Tools and Technologies
CARAT relies on the CliniMACS® Cell Separation principle that has become an established technology since its introduction in 1997 for the development of GMP-compliant manufacturing processes for cellular products. Since then, more than 50,000 patients were treated with CliniMACS-derived cell products and notably, in 2014 the CliniMACS System obtained approval by the U.S. Food and Drug Administration (FDA) for a specific treatment of Acute Myeloid Leukaemia (AML). To date, the CliniMACS System is the only technology worldwide for clinical enrichment of cellular products within a closed system.
As established in manifold industries, the best way to standardize a complex process is to automate it as much as possible. Along this line, the CliniMACS Prodigy® is a further central innovation to CARAT as it represents the next generation of cell processing by simplifying and standardizing conventional processes. In principle, the automated device is capable of performing all necessary steps from cell preparation, enrichment, washing, activation, transduction, expansion to final formulation and sampling in a closed sterile, single-use tubing set (see Figure; Apel et al., 2013).
Already used in clinics for the enrichment of stem cells and the preparation of virus-reactive T-cells, the CliniMACS Prodigy will be adopted as a generic platform for integrated manufacturing of genetically engineered CAR T-cells with minimal user interaction(WP1 and 5). This fully automated approach will greatly simplify and improve robustness and reproducibility of the manufacturing procedure. Integration of enabling technologies from WP1,2,3 and 4 will finally result in the novel CARAT process illustrated in the figure below.
Key functional units of the CliniMACS Prodigy. The instrument has been developed to fully automate and standardize the manufacturing process of cellular products. It maintains a closed system by using disposable tubing sets equipped with multiple input lines with tubing connections for use of sterile docking devices. Output lines offer in-process-control (IPC) if needed. This closed system meets the requirements of GMP-grade processing of almost any kind of cellular products and may allow reducing clean room requirements.
Central to the Prodigy is the centrifugation and cell culture chamber. The “CentriCult chamber” enables density-based cell separations including erythrocyte reduction and plasma harvesting, cell washing, cell culture, and final product formulation. Magnetic cell separation is facilitated in a separate unit. Various sensors allow optical control of the process as well as measurement of temperature, pressure and liquid flow.
To facilitate the most efficient selection of cellular starting material, Miltenyi will apply an absolutely new and unique technology in CARAT for isolating ultrapure T-cell subpopulations: microchip-based clinical cell separation with the MACSQuant Tyto, to be released this year (Linton & Oram, 2013). This system is based on a novel technological principle, completely different from traditional droplet-based fluorescence activated cell sorting (FACS). It performs the separation process in a fully closed and disposable cartridge within a microfluidic structure. Central to this technology is a patented microchip, capable of high-frequency valving (Fig. 7).
The sterile, closed, and disposable fluidics format prohibits cell cross-contamination and minimizes the risk of microbial contamination. Therefore, the MACSQuant Tyto easily fulfils GMP requirements and, combined with the CliniMACS system for pre-enrichment, is ideally suited for CAR T-cell purification and expansion.