Expansion and differentiation of ex vivo cultured erythroblasts in scalable stirred bioreactors

Biotechnol Bioeng. 2022 Nov;119(11):3096-3116. doi: 10.1002/bit.28193. Epub 2022 Aug 5.


Transfusion of donor-derived red blood cells (RBCs) is the most common form of cell therapy. Production of transfusion-ready cultured RBCs (cRBCs) is a promising replacement for the current, fully donor-dependent therapy. A single transfusion unit, however, contains 2 × 1012 RBC, which requires large scale production. Here, we report on the scale-up of cRBC production from static cultures of erythroblasts to 3 L stirred tank bioreactors, and identify the effect of operating conditions on the efficiency of the process. Oxygen requirement of proliferating erythroblasts (0.55-2.01 pg/cell/h) required sparging of air to maintain the dissolved oxygen concentration at the tested setpoint (2.88 mg O2 /L). Erythroblasts could be cultured at dissolved oxygen concentrations as low as 0.7 O2 mg/ml without negative impact on proliferation, viability or differentiation dynamics. Stirring speeds of up to 600 rpm supported erythroblast proliferation, while 1800 rpm led to a transient halt in growth and accelerated differentiation followed by a recovery after 5 days of culture. Erythroblasts differentiated in bioreactors, with final enucleation levels and hemoglobin content similar to parallel cultures under static conditions.

Keywords: cell culture; cultured blood; erythropoiesis; red blood cell; scale-up; stirred tank bioreactor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bioreactors*
  • Cell Differentiation
  • Cell Proliferation
  • Cells, Cultured
  • Erythroblasts*
  • Hemoglobins
  • Oxygen


  • Hemoglobins
  • Oxygen