The Profile of CD71+ Erythroid Cells in Korean Children: A Pilot Study.

Background: CD71+ erythroid cells (CECs) play a complex immunoregulatory role. Methods: Flow cytometry was used to assess CECs in 84 individuals, from preterm infants to adults, divided into 5 age groups, 12 from infants under 6 months, 16 from young children (6 months-5 years), 24 from children (6-10 years), 22 from adolescents (11-19 years), and 10 from adults (≥20 years). Results: CECs are universally present at very low frequencies, except in individuals younger than 6 months (P < 0.001). Although preterm infants tended to have a higher median CECs than full-term infants, this difference was not statistically significant. Among individuals over 6 months, CECs showed significant negative correlations with hemoglobin (r = -0.448, P < 0.001) and hematocrit (r = -0.416, P < 0.001), but no such correlations were found in younger infants. Conclusions: CECs are present across all age groups, with higher levels in early infancy.