Neocyte-enriched blood does not provide a survival advantage for red cells when compared to conventional filtered blood.

Background and objectives: Red blood cell (RBC) concentrates are stored at 1-6°C for up to 42 days, but storage lesions can lead to wastage. Pooled neocytes may extend RBC shelf-life, benefiting patients who require frequent transfusions. This study aimed to improve the longevity of stored RBCs by isolating neocytes and comparing the rate of haemolysis, biochemical changes and viability with filtered blood.

Materials and methods: Thirty filtered units were processed. Neocytes were extracted and enriched with saline-adenine- glucose-mannitol. Both filtered and neocyte-enriched units were stored for 42 days. Samples were analysed every 14 days for RBC count, mean cell volume (MCV), mean cell haemoglobin concentration (MCHC), haemoglobin, sodium and supernatant haemolysis.

Results: There was no significant difference in red cell count between filtered and neocyte-enriched units (p = 0.27). Both types showed increased mean corpuscular volume and decreased MCHC over the 42 days, with no significant differences observed (p ≥ 0.05). Sodium levels in the supernatant decreased while percentage supernatant haemolysis increased steadily in both units, albeit without significant differences (p ≥ 0.05). The haemoglobin remained stable for both unit types.

Conclusion: Overall, neocyte-enriched blood did not demonstrate any longevity advantage compared to pre-stored leucocyte-reduced RBCs using the conventional manual collection method. These findings align with previous studies using various neocyte collection methods. Feasibility was highlighted as the main challenge, as many of these methods have proven too expensive and laborious.