Immortalized stem cells produce bigger, better blood batches

Donating blood saves lives, but there's never enough, especially when the difficulties of storage and matching blood types are taken into account. Artificial blood has been in the works for years, but it's held back by the fact that the stem cells it's grown from can only produce so many red blood cells. 

Now, researchers at the University of Bristol and NHS Blood and Transplant may have busted that barrier, by developing immortalized cell lines that can be cultured indefinitely to produce artificial blood on a much larger scale.

Rather than turn adult stem cells directly into mature red blood cells, the Bristol team's solution was to not cut out the middleman – in this case, premature red blood cells called erythroblasts, that then produce mature cells – but to "immortalize" these erythroblasts so a continuous supply of mature red blood cells can be generated, thereby boosting the scale of artificial blood production.

"Previous approaches to producing red blood cells have relied on various sources of stem cells which can only presently produce very limited quantities," says Jan Frayne, first author of the study. "By taking an alternative approach we have generated the first human immortalized adult erythroid line (Bristol Erythroid Line Adult or BEL-A), and in doing so, have demonstrated a feasible way to sustainably manufacture red cells for clinical use from in vitro culture."

As important as the breakthrough is, the team is careful to note that large-scale production of artificial blood is still many years away. For now, the aim is to complement, not replace, donations, and the first people to receive the BEL-A blood will probably be those with rare blood types or chronic illnesses.