Characterization of human mesenchymal stem cells from multiple donors and the implications for large scale bioprocess development

Thomas R.J. Heathman, Qasim A. Rafiq, Alexander K.C. Chan, Karen Coopman, Alvin W. Nienow, Bo Kara, Christopher J. Hewitt

Centre for Biological Engineering, Loughborough University, Leicestershire LE11 3TU, UK.

Abstract

Cell-based therapies have the potential to contribute to global healthcare, whereby the use of living cells and tissues can be used as medicinal therapies. Despite this potential, many challenges remain before the full value of this emerging field can be realized. The characterization of input material for cell-based therapy bioprocesses from multiple donors is necessary to identify and understand the potential implications of input variation on process development. In this work, we have characterized bone marrow derived human mesenchymal stem cells (BM-hMSCs) from multiple donors and discussed the implications of the measurable input variation on the development of autologous and allogeneic cell-based therapy manufacturing processes. The range of cumulative population doublings across the five BM-hMSC lines over 30 days of culture was 5.93, with an 18.2% range in colony forming efficiency at the end of the culture process and a 55.1% difference in the production of interleukin-6 between these cell lines. It has been demonstrated that this variation results in a range in the process time between these donor hMSC lines for a hypothetical product of over 13 days, creating potential batch timing issues when manufacturing products from multiple patients. All BM-hMSC donor lines demonstrated conformity to the ISCT criteria but showed a difference in cell morphology. Metabolite analysis showed that hMSCs from the different donors have a range in glucose consumption of 26.98 pmol cell^-1 day^-1, Lactate production of 29.45 pmol cell^-1day^-1 and ammonium production of 1.35 pmol cell^-1 day^-1, demonstrating the extent of donor variability throughout the expansion process. Measuring informative product attributes during process development will facilitate progress towards consistent manufacturing processes, a critical step in the translation cell-based therapies.

Keywords: Bioprocess design; Characterization; Biomedical; Scale-up; Tissue cell culture; Human mesenchymal stem cells.