Manufacturing methods can damage red cells

Platelet-derived CD41a+ EVs were highest in non-leukoreduced and Trima RCCs and did not change significantly during storage.

White blood cell-derived CD11b+ and CD66b+ EVs were low in most RCCs (though not in Trima and FenMAN-non-LR RCCs), and their levels did not significantly change during storage.

White blood cell-derived CD14+ EVs were negligible in fresh RCCs but increased in several RCCs during storage (FenMAN, Alyx, MCS+, and Trima).

Next steps

“There must be more testing of the apheresis collections equipment, blood bags, leukoreduction filters, and other variations in manufacturing methods to determine what single element or combination of elements in the various red blood cell manufacturing processes result in high levels of DAMPs and why,” said Michael Busch, MD, PhD, of Blood Systems Research Institute in San Francisco, California.

“We also need to understand how mitochondrial DAMPs are involved in adverse reactions to red blood cell transfusions,” added Sonia Bakkour, PhD, also from Blood Systems Research Institute.

“Some recently published studies on platelet components link high levels of mitochondrial DAMPs to adverse transfusion reactions. We need to see if DAMPs have similar adverse effects on recipients of red blood cell transfusions.”

“We think that our research could lead to finding the best way to manufacture red blood cells,” Dr Acker noted.

“It’s clear now that manufacturing methods matter. We . . . are keen to explore what’s in the blood bag or in the filters or in the tubing, for example, that can be minimized or eliminated, improving the outcome in patients who receive blood transfusions.”