Evaluation of the Impact of a New Cooling Cell Processor System on Islet Cell Isolation Facility.

ABSTRACT

Standard cell therapy equipment, including the gold standard cell processor to purify human islets for clinical transplantation, is rarely refrigerated, potentially exposing cells to elevated temperatures during the centrifugation step. Custom cooling systems have a direct benefit on human islet viability and function. The current study was designed to test the effectiveness of a newly developed, readily available cooled cell processor system requiring minimal modifications and to evaluate its impact on human cell viability and the GMP cleanroom environment. The cooler system, a mechanically refrigerated heat exchanger set at -30 °C was used to deliver cooled medical grade dry air to the cell processor bowl through a hole drilled in the centrifuge cover. With the limited availability of pancreas donors in Qatar, system validation was done with continuous density gradient purification of pooled human bone marrow buffy coat. Sterility, turbulence, and particle count were measured in class C and class B clean room environments. No turbulence developed around the cooled cell processor, and no excess 0.5 µm and 5 µm airborne particulates were generated as per cleanroom GMP standards. At the beginning and end of the collection steps, the temperature rose respectively to 21.50 °C ± 0.34 °C and 21.93 °C ± 0.20 °C in the non-cooled cell processor and to only 10.9 °C ± 0.17 °C and 11.16 °C ± 0.35 °C in the cooled- cell processor (p <0.05). The cooled cell processor led to both improved recovery (98%) of the mononuclear cell fraction and viability (100% ± 2%) post-processing. The new cooling system effectively reduces the heat produced by the cell processor while having no particulate impact on the GMP clean room environment. The cooled cell processor described here is an inexpensive ($16,000 without including taxes, customs clearance, and transportation) and minimally invasive method to provide robust cooling. Currently, this technology in the GMP cell therapy facility is being applied to human islet cell isolation and transplantation for the clinical program.