The acCellerator: flexible cell culture from RTS.

Cell culture, either for the cells themselves or their products, is traditionally a manual process that demands hours of repetitive, painstaking work to ensure absolute sterility under exacting conditions. Growing a mammalian cell culture for use in a screen for drug activity or toxicity typically takes 48 hours, so almost half the working week is gone before screening can begin.

But with automated cell-culture systems, screening could start on Monday morning on cultures left to grow over the weekend. Robotic systems can also provide a consistency of procedure and sterility that the best technicians cannot match, ensuring less variability between batches.

The Automation Partnership (TAP) in Royston, UK, introduced its pioneering Cellmate workstation in the late 1980s for the relatively large-scale production of therapeutic reagents and vaccines. This has now been joined by a new system, SelecT, developed in association with a consortium of six major drug companies, including GlaxoSmithKline and Pfizer.

SelecT is aimed at labs that need an automated system for processing up to 168 different mammalian cell lines simultaneously, making it ideal for multiple batches. The system can automatically maintain, expand, process and harvest multiple cell lines, assess their viability, and distribute them onto a maximum of 300 microtitre plates. “Cellmate is not so good at dealing with just-in-time production of ready-to-go microplates,” says Mark Beggs, head of consulting at TPA. “SelecT can handle all the capabilities you need to take cells through to incubation to microplates.”

Other commercial systems provide an even greater level of integration. Cytogration, a subsidiary of Brandel in Rockville, Maryland, has developed a robotic system that performs both cell culture and screening assays for drug candidates. The standard system handles up to 504 plates, and automates cell production, preparation of membrane-bound cells and in vitro screening.

An automated system has primarily to maintain a stable environment and reduce the risk of contamination, says Sean Sales, applications consultant at RTS Life Sciences in Manchester, UK. The system also needs to be dynamic in terms of knowing everything, so that the robot itself isn't slowing things down, he says. RTS has developed a flexible cell-culture system called acCellerator which has a very simple liquid-handling method and three parallel robot arms to process the flasks and plates in parallel. “It has a number of peristaltic pump units that allow a very short liquid line for reagents, so you don't have a lot of tubing to change over between cell lines,” says Sales.