There is currently much expert divergence on the question of what role point-of-care cell washing and concentration may play in the future of cell therapies. On that topic, we recently posted a more extensive background on the issues related to post-thaw cell washing on CellTherapyBlog.com.
There is also a long-standing and active discussion thread in the LinkedIn Cell Therapy Industry Group, entitled “Clinical preparation of frozen Cell Therapy products” on the topic. Indeed, as a result of a post in that thread, we were invited to post here a short summary of a technology we believe shows promise for bringing a new level of innovation to cell washing.
The Ensura-Sep™ Cell Washing Canister is an emerging technology that has been developed for the washing of a cell suspension at the point of care. Cell washing and cell concentration are achieved in a single centrifugation step. The technology is based upon density phase washing with a proprietary centrifugation canister apparatus and density reagent. The density reagent is composed of ingredients approved for parenteral injection. One version of the canister employs an angular rotor for volumes of 40 ml or less and for larger volumes a different canister is employed for volumes up to 500 ml. Potential cell washing applications include removal of DMSO, density gradient reagents including Ficoll, enzymes such as collagenase, red cell lysing reagents, antibodies, or other excipients prior to clinical infusion.
The first step involves adding the supplied density blocking reagent to the canister’s vertical chamber via a sterile port. The cell suspension is then added to a second chamber designated as the reservoir chamber. Upon centrifugation, cells pass through the density blocking solution and pellet whereas the cell suspending medium remains behind due to the density differences between reagent and cell suspending fluid. The supernatant is aspirated from the reservoir chamber and the cells are re-suspended in and harvested from the vertical chamber via a final aspiration into a syringe through a swabbable needle-less access port. The technique is simple and rapid to perform .
For those looking for this kind of solution, the Cell Therapy Group is pleased to be working with Stem Cell Partners on bringing to market what we believe is potentially a simple, quick, cost-effective, easy-to-use density phase washing centrifugation device utilizing biocompatible reagents and commercial centrifuges. For a quick review of the technology, see www.cellwasher.com
We are working on providing guidance to Stem Cell Partners in regard to different configurations and sizes of that device for different applications. Stem Cell Partners is also working with our clients to design custom canisters and reagents to meet their specific requirements.
While we believe the Ensura-Sep Cell Washer may enable a simple and rapid washing and concentration of a cell suspension in a single centrifugation step, CTG is also working with other companies who are pursuing other solutions using different technologies such as filtration. With the successful adoption of these technologies, Cell Therapy developers may have more flexibility in determining final product formulation.