Biological BIG Brother

Cellular therapies have the potential to transform healthcare as we know it. But how best do we scale up this technology? The key, thinks Steve O’Reilly, is to keep an automated watchful eye on cell growth  

Rapid and significant technological innovations in life sciences are offering hope for the chronically ill. Hope, for these individuals, often lies in something as small as a human cell. Cellular therapies offering regenerative capabilities are enhancing this hope for patients of all ages. But as healthcare services for those with diabetes, cancer, heart disease, and neurological diseases expand – clinical, diagnostic, and pharmacological laboratories will have to increase their investment in precision automation in order to ‘scale-up’ to meet demand.

A wide range of enabling technologies such as high resolution optics, precision modular automation, precision fluid handling, and quantitative image analysis are all being embedded in advanced instruments and equipment. This supports an ecosystem optimised for the specialised work of cell technicians giving, for example, greater ability to qualify stem/progenitor cells and to manipulate key colonies of interest. It is becoming widely recognised that stem cell therapy will be instrumental in transforming healthcare and improving treatment of some of the most devastating diseases, and the automation of precision processes is a key aspect of achieving success.

Today, most cell-based research and cell fabrication strategies are supported by manual processes

The problem that many researchers in this field have faced is the inability to use large field of view (LFOV), high resolution optics to image cell cultures to monitor and quantify cell-based changes. Additionally, many available devices lack the accuracy and precision required for rigorous sampling, transfer, or deletion of specific cells or colonies.

Today, most cell-based research and cell fabrication strategies are supported by manual processes. Colonies are often visually assessed and identified, counted or selected, and manually transferred by a lab technician working with a microscope, viewing a sample through a narrow field of view. Given the mundane and highly subjective nature of this method, results can be very inconsistent and of course subject to human error.

Quantitative methods for cell and colony metrics are typically limited to destructive assays, in which groups of cells are combined and analysis of the proteome or gene expression of the entire population is assessed. Although these destructive methods provide accurate quantitative information, they only provide an average assessment of the cell colony type. Automated image-based systems can allow for both accurate quantitative metrics of biological performance. In addition, these metrics can be applied on a cell-by-cell or colony-by-colony level, as well as at the level of gross population metrics.

In contrast, a manual colony count – the most common method for quantifying the number of stem cells or progenitors in a given sample – is highly variable. Furthermore, beyond just a number of colonies, manual counts fail to provide quantitative data on the features of each colony that was counted. Nor do such counts create a durable record of the status of each colony at the time of assay. Despite the enormous progress and promise in the field of cell therapy development, unresolved challenges relating to accuracy, repeatability and continuity continue to plague the community exploring cell-based diagnostics.

Automated handling equipment in particular needs to support a heightened level of dexterity and control

The size and nature of cells means they must be handled with precision and care. Automated handling equipment in particular needs to support a heightened level of dexterity and control. When looking at typical therapy processes, there are effectively two major processes:

• Scanning and identification – using optics, in conjunction with motion systems and control algorithms, to find cells or clusters of cells of interest and identify their location in 3D space.
• Cell selection process – Utilising interactive surgical tools to selectively biopsy cells of interest, remove undesired cells, or transplant desired cells into a site where they can be further expanded, processed, or studied.

Companies with knowledge and expertise in motion and control technologies for a wide range of industry sectors are using their capabilities to provide valuable automation solutions for the life sciences sector. As an example, Parker Hannifin has worked with leading experts, medical institutions and providers of platforms that combine LFOV imaging and control capabilities with precision instrumentation, fluidics, and documentation. Such systems open new opportunities for the discovery and development of stem cell therapeutics. These same features also provide new avenues for quantitative personalised cell-based diagnostics, optimisation of biomaterials and bioactive surface design, and drug discovery applications.

The central core of such devices is a high quality automated inverted microscope and CCD camera, with both brightfield and fluorescent imaging options. Several other important enabling features are added to this standard laboratory equipment. These include a high precision low-profile XY system enabled by miniature linear positioners which provide sub-micron level, smooth positioning. These units are able to position the cell carrying trays in the optical system with the required accuracy and repeatability.

Integrated high resolution feedback devices allow the robot to precisely determine the exact position of cells. Custom trays allow the use of any standard cell culture plate or dish, as well as options for automatic loading and unloading of plates. The low profile of such designs is key for keeping optics in the focal range of the microplates.

A rigid machine base is another important element. This structure must provide a very stiff, stable platform with integrated isolating pads to minimise the vibration the robot might experience from external sources. High precision miniature ballscrews are used to adjust filters automatically to optimise the lighting of the cells and a tip load and remove station facilitates the disposal of tips used in picking cells of interest without human intervention.

The overall operation of such precision life science equipment is often achieved using a high performance motion controller

Another important element of the system is Z-axis positioners which enable the picking and placing of cells or fluids. The first axis can use a syringe pump to aspirate the cells of interest. A second axis is used for precise media removal around the area of interest, and a third allows for additional steps for multiple fluids or reagents. The overall operation of such precision life science equipment is often achieved using a high performance motion controller. Functioning as the brains of this robot, it is used to coordinate the motion between all axes and motion for fault conditioning.

The combined precision and imaging features of such cytocentric systems have enabled leading researchers to collect data rapidly. Images taken from systems are of high enough quality and can be digitally stitched together to provide LFOV analysis and monitoring of colonies and cell populations. Due to the high repeatability of such systems, each cell or colony can be given a digital address and revisited by the motion system at a later date to monitor time dependent changes.

The future of cell therapy development involves having quantitative and reproducible standards that enable the determination and management of critical quality attributes for cells and colonies, in order to provide optimal safety and efficacy. Meanwhile, technology from motion and control specialists, often with origins in vastly different sectors, will continue to develop solutions with modularity, scalability, and precision to help all parties continue to improve the reproducibility of cell-based experiments, thereby accelerating the development of life changing cellular therapies.

Author: Steve O’Reilly is Market Development Manager for Life Sciences at Parker Hannifin