Red blood cells on tap
Supplying enough blood for medical procedures is becoming increasingly difficult and expensive. The cost of transfusion services is inflating mainly because there is a risk of contamination from HIV and other infectious agents such as Creutzfeldt-Jacob disease and consequent patient safety measures. To provide an answer to these mounting problems, the EU-funded project Redontap are underway in the development of a controlled bioreactor where haematopoietic stem cells (HSCs) differentiate into RBCs (erythrocytes). Achievement of this goal basically comprises three steps. The first is to establish an environment where controlled proliferation and differentiation of HSCs into mature erythrocytes can be isolated and purified. So far the Redontap scientists have manipulated cytokine levels to control the development path and the nutrients in the bioreactor for optimum production levels. The researchers have also tested different environmental conditions and stroma to define stromal support replacement strategies. Next, project workers created modified bioactive surfaces that will specifically capture the initial asymmetrically dividing cells. Two peptides have been tethered onto gold-coated glass, and experiments have been conducted with varying concentrations of the peptides. Lastly, the design and production of the bioreactor has resulted in a working prototype that is undergoing further testing. Bioreactor features include miniaturised sensors for pH, dissolved oxygen, foam and temperature, as well as adaptable cultivation modes (batch, fed-batch, continuous and perfusion). The Redontap project is due for completion in 2014 and research is expected to provide creation of clinical-grade RBCs. As it is estimated that costs for blood transfusion services run to EUR 30 billion alone, the economic and health impact of this research promises to be very significant.