Iron-deficient erythropoiesis in blood donors and red blood cell recovery after transfusion: initial studies with a mouse model.

BACKGROUND: Most frequent red cell (RBC) donors and many first-time donors are iron deficient, but meet haemoglobin standards. However, the effects of donation-induced iron deficiency on RBC storage quality are unknown. Thus, we used a mouse model to determine if donor iron deficiency reduced post-transfusion RBC recovery.

METHODS: Weanling mice received a control diet or an iron-deficient diet. A third group receiving the iron-deficient diet was also phlebotomised weekly. This provided 3 groups of mice with different iron status: (1) iron replete, (2) mild iron deficiency with iron-deficient erythropoiesis, and (3) iron-deficiency anaemia. At ten weeks of age, blood was collected, leucoreduced, and stored at 4 ºC. After 12 days of storage, 24-hour (h) post-transfusion RBC recovery was quantified in recipients by flow cytometry.

RESULTS: Before blood collection, mean haemoglobin concentrations in the iron-replete, iron-deficient, and iron-deficiency anaemia donor mice were 16.5±0.4, 11.5±0.4, and 7.0±1.4 [g/dL± 1 standard deviation (SD)], respectively (p<0.01 for all comparisons between groups). The 24-h post-transfusion RBC recoveries in recipients receiving transfusions from these three cohorts were 77.1±13.2, 66.5±10.9, and 46.7±15.9 (% ±1 SD), respectively (p<0.05 for all comparisons between groups).

DISCUSSION: In summary, donor iron deficiency significantly reduced 24-h post-transfusion RBC recovery in recipient mice. RBCs from mice with mild iron deficiency and iron-deficient erythropoiesis, with haemoglobin levels similar to those used for human autologous blood donation, had intermediate post-transfusion RBC recovery, as compared to iron-replete donors and those with iron-deficiency anaemia. This suggests that, in addition to the effects of iron deficiency on donor health, frequent blood donation, leading to iron-deficient erythropoiesis, may also have adverse effects for transfusion recipients.