Effects of erythropoietin on circulating hemotopoietic progenitor cells in premature infants

Objective To study the efficacy and safety of erythropoietin(EPO)in anemic premature infants,and explore the possible mechanism of erythropoietin on premature infants. Methods A randomized controlled study was prospectively conducted.Twenty-four premature infants were divided into treatment and control group with 12 in each.The treatment group received the same treatment as the control group besides receiving EPO 250 U/kg per time,3 times weekly and 4 weeks totally.The number of circulating hematopoietic progenitor cells from 24 premature infants before and two weeks after treatment were determined by semisolid culture technique, and the counts of total white blood cell, neutrophil, lymphoeyte, monocyte,platelet and reticulocyte,hemoglobin were compared between the two groups.ResulIs Compared with the control group.EPO treatment for two weeks did not affect the number of burst forming unit-erythroid,colony forming unit-granulocyte/macrophage,colony forming unit-Mix and colony forming unit-megakaryocyte(P＞0.05),but there was a significant elevation in the number of colony forming unit-erythroid in the treatment group than in the control group(57±20 vs 34±13,P＜0.05).The counts of total white cell,absolute neutrophil,lymphocyte,monocyte and platelet were not significantly decreased between the treatment and control group during the study of 4 weeks(P＞0.05).While all the infants received EPO had higher hemoglobine level and reticulocyte counts after one to four weeks of treatment (P＜0.05).In the fourth week,hemoglobin level of the treatment group was higher than controls [(152±14)g/L vs(128±11)g/L,P＜0.05]. Conclusions EPO is effective and safe for anemic premature infants both on ctinic and hematopoietic progenitor cell level.EPO could improve hemoglobin probably by taking effect on late erythroid progenitor cells and their later stage cells. Key words: Infant,premature,diseases; Anemia; Hemotopoietic stem cells; Erythropoietin