Squish or Burst? Importance of mechanics in scale-up of downstream processing of cellular therapies

There are currently whole cell therapeutic treatments in development for a wide-range of “mass market” diseases. It is commercially inconceivable to consider an autologous (one donor, one recipient) model for indications affecting large populations; therefore a shift towards an allogeneic (one donor, many recipient) model is desirable.

There is currently much debate regarding the regulatory landscape for cellular therapies, however we believe that the regulatory bodies are certain to require as stringent a demonstration of purity as is currently demanded for protein therapeutics. This will be especially the case for allogeneic therapies. Consequently, there is an urgent need to address the challenges associated with large-scale downstream processing of cell therapies

This work will present results from within our group investigating several novel techniques to separate cells of different phenotypes and stage of differentiation based on physical and mechanical properties rather than the more currently used “gold standard” of biological surface markers. Specifically the research presented here will demonstrate promising results and progress made over the last two years in the areas of:

• Understanding the potential of cell-cell separation on the basis of elastic modulus. Here, we identify differences in cell stiffness, expressed as cell elastic modulus (CEM using atomic force microscopy and real-time deformability cytometry to characterize the stiffness of cell populations and to drive separation performance based on this.
• Cell-cell separation using inertial focusing devices to separate on a combined size/shape/density basis. We have been able to show segregation of nucleated and enucleated cells at the latter stages of manufacture of red blood cells (RBCs) using a custom-designed inertial focusing device that can be stacked to enable scale-out to high throughputs.

Our results demonstrate the principle of a scalable, label-free, solution for separation of heterogeneous cell populations deriving from human pluripotent stem cells through a number of approaches.