Transfusion of red blood cells after prolonged storage produces
harmful effects that are mediated by iron and inflammation.
Blood. 2010 Mar 18.
Hod EA, Zhang N, Sokol SA, Wojczyk BS, Francis RO, Ansaldi D,
Francis KP, Della-Latta P, Whittier S, Sheth S, Hendrickson JE,
Zimring JC, Brittenham GM, Spitalnik SL.
Department of Pathology and Cell Biology, Columbia University College
of Physicians and Surgeons, New York, NY, United States;
Although red blood cell (RBC) transfusions can be lifesaving, they
are not without risk.
In critically ill patients, RBC transfusions are associated with
increased morbidity and mortality, which may increase with prolonged
RBC storage before transfusion.
The mechanisms responsible remain unknown.
We hypothesized that acute clearance of a subset of damaged, stored
RBCs delivers large amounts of iron to the monocyte/macrophage
system,
inducing inflammation.
To test this in a well-controlled setting, we used a murine RBC
storage
and transfusion model to show that the transfusion of stored RBCs, or
washed stored RBCs, increases plasma non-transferrin bound iron
(NTBI),
produces acute tissue iron deposition, and initiates inflammation.
In contrast, the transfusion of fresh RBCs, or the infusion of stored
RBC-derived supernatant, ghosts, or stroma-free lysate, does not
produce
these effects.
Furthermore, the insult induced by stored RBC transfusions synergizes
with sub-clinical endotoxinemia producing clinically overt signs and
symptoms.
The increased plasma NTBI also enhances bacterial growth in vitro.
Taken together, these results suggest that, in a mouse model, the
cellular
component of leukoreduced, stored RBC units contributes to the
harmful
effects of RBC transfusion that occur after prolonged storage.
Nonetheless, these findings must be confirmed by prospective human
studies.
PMID: 20299509
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