"We took a representative sample of data to compare the automated system to traditional manual methods and found that it is more than fulfilling the role we envisaged for it"
The Accellerator was installed at AstraZeneca's Charnwood site in Loughborough, UK several months ago.
RTS and AstraZeneca report its performance to be solid.
Gary Allenby, AstraZeneca's associate principal scientist in HTS commented: "We took a representative sample of data to compare the automated system to traditional manual methods and found that the acCellerator is more than fulfilling the role we envisaged for it.
"I believe that its methodology will make the cells on which we perform our assays more consistent, ultimately improving our data output".
The Accellerator is a robotic system that provides total automation of cell growth, harvest, count, passage and plating.
This system uses a combination of industrial robotics, easy to use dynamic scheduling software and the latest instrumentation and environmental control systems.
Accellerator has proved to be very robust.
This reliability has been achieved through the use of proprietary equipment, simplified processes and the use of RTS Sprint to ensure a consistent environment for repeatable cell production at optimum throughput.
With Accellerator harvesting, passaging and plating cells seven days a week, the bottleneck created by AstraZeneca's uHTS has effectively been removed and the throughput of the screening process dramatically increased.
Parallel processing with Sprint scheduling software enables over seven hundred 384 well plates of cells per day to be produced.
In addition, the graphical user interface centered on an ordering system, so that orders can be easily prioritised or demoted.
Data generated using both CHO and HEK cells show that the use of this automated system yields cells with high cell viability and quality.
Consistency of data (Z factor) has been demonstrated in Flipr assays using cells and plates generated on Accellerator.
Using the trypan blue exclusion method to quantify cell viability, Accellerator-maintained cells were compared with those maintained by manual methods.
Control cells had a viability of 92 % and a cell number of 11.6x105/ml.
The Accellerator produced cells had a viability of 90% and cell number of 12.0x105/ml.
Using the Accellerator system the quality of cells produced was maintained whilst using only a fraction of the cell culture operators time.
Microscopic examination of both groups of cells revealed no significant differences in growth characteristics.
Upon observation, the Accellerator method of dispersing cell clumps after cell dissociation was judged to be as effective as manual trituration using a pipette.
Automated Flipr screening of a hundred 384 well plates produced using Accellerator, demonstrated consistency of response equal to, or better than, that generated by plates produced by manual cell culture techniques.
The quality of responses and variability in wells within each plate was assessed using a Z' factor, where one is ideal and zero is unacceptable.
In HTS, a Z' factor of 0.4 or greater is generally considered acceptable. Plates generated to validate the Accellerator elements achieved a Z' of 0.6 or greater.
These data demonstrate that during this 100 plate screening run, the cells were of a consistently high quality.
Gary Allenby explained: "There aren't many others in the world who perform cell-based assays in the same numbers as AstraZeneca.
"With readers like the Flipr and the In Cell analyser becoming more widely used, the tide is definitely moving towards the adoption of cell-based HTS by the pharmaceutical sector as a whole.
"Once this happens, the requirement for large quantities of high quality cells will become the norm".
As well as the speed and round-the-clock nature of working, various other advantages to the use of Accellerator were noted.
One of these is that both on-line cell counting and automatic dilution calculation are incorporated into the system.
This eliminates inconsistencies that can arise from differences in individual counting techniques employed by different cell culture operators.
Another was found to be that the system's dry block heater units provide faster and more controllable temperature regulation at the dissociation stage than returning flasks to the incubator or carrying out this step at room temperature.
This optimises consistency of passaging conditions.
