Validation of the nant 001 bioreactor system for automated adipose-derived mesenchymal stem cell expansion

Abstract

Background & Aim Adipose-derived mesenchymal stem cells (ASCs) are an attractive choice for regenerative therapies due to their minimally invasive method of isolation. As with any source, the need for cell expansion to produce therapeutically useful quantities of cells bring challenges. Manual production of stem cells is labor-intensive, expensive and poses a high risk for contamination. The NANT 001 is an innovative bioreactor that has evolved from manual cell culture principles to introduce a high level of automation. This work reports on the validation of this system for the production of ASCs compared with conventional manual expansion processes. Methods, Results & Conclusion ASCs at passage 1 from a healthy donor were suspended in α-MEM supplemented with 10% fetal bovine serum, seeded into either the bioreactor system or Corning 636 cm2 CellSTACK culture chambers at a density of 2000 cells/cm2 and incubated at 37°C, 5% CO2. After 24 hours, and when the cells reached 50% confluency, the monolayer was washed with PBS and the growth media was replaced. Cells were automatically harvested 24 hours after reaching 90% confluence. Three validation runs were performed. Growth kinetics, cell viability, sterility, trilineage differentiation capacity and surface immunophenotype were assessed. Cell growth kinetics and yield from the bioreactor were comparable to those obtained from the manual process. On average, an inoculation of 1.3 × 106 cells yielded 52 × 106 cells from the NANT 001 and 55 × 106 from the manual process in a 6-day expansion. Viability was not affected by the bioreactor process with >95% cell viability recorded from all 3 runs. Supernatants from all cell cultures tested negative for microbial contamination. There were no significant differences in the adipogenic, osteogenic and chondrogenic differentiation propensity of the cells regardless of expansion process. Expression of surface markers in all cases was consistent with IFATS standards for ASC phenotype. Collectively, these data illustrate the potential of using the NANT 001 bioreactor for automated expansion of ASCs. The risk of contamination is decreased by reducing the use of open procedures. Ongoing work consists of a GMP validation of the system for the expansion of ASCs from the stromal vascular fraction of adipose tissue. Based on these observations, the NANT 001 bioreactor represents an effective option for closed, automated and aseptic manufacturing of autologous cell products for applications in cell therapy and regenerative medicine.