Related Experiment Video
Updated: Jan 13, 2026
Pan-myeloid Differentiation of Human Cord Blood Derived CD34+ Hematopoietic Stem and Progenitor Cells
Published on: August 9, 2019
Circulating CD34 Positive Cells and Immunological Responses in Extremely Preterm Infants
Ulrika Sjöbom1,2, Helena Barreto Henriksson2,3,4, Anders K Nilsson2
1Learning and Leadership for Health Care Professionals, Institute of Health and Care Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Insights
Monitoring hematopoietic stem and progenitor cells (CD34+) in preterm infants is feasible using residual blood. CD34+ cell counts showed high variability and correlated with infections, offering insights into early immune function.
Area of Science:
- Neonatal Hematology
- Immunology
- Developmental Biology
Background:
- Preterm birth can disrupt fetal hematopoietic system development.
- Hematopoietic stem and progenitor cell (CD34+) dynamics in preterm infants are understudied due to limited blood volumes.
- Residual blood samples offer a viable alternative for studying CD34+ cells in this population.
Purpose of the Study:
- To characterize the dynamics of circulating CD34+ cells in extremely preterm infants.
- To explore associations between CD34+ cell counts and prenatal/postnatal clinical events.
- To assess the feasibility of using residual clinical blood for longitudinal monitoring.
Main Methods:
- Longitudinal analysis of residual blood samples from nine infants born <28 weeks gestational age.
- Flow cytometry assessment of CD34+ cell counts.
- Measurement of nucleated red/white blood cells and hemoglobin concentration.
Main Results:
- Observed high inter- and intra-individual variability in CD34+ cell counts.
- CD34+ cell proportion decreased significantly by day 7 post-birth.
- Elevated CD34+ cell levels were associated with maternal or infant infections.
Conclusions:
- Longitudinal monitoring of CD34+ cells in extremely preterm infants is feasible using residual blood.
- Preliminary data suggest links between CD34+ cell dynamics and early-life infections.
- Further research in larger cohorts is warranted to confirm findings and explore immune function.
Background:
The dynamic changes of the hematopoietic system during fetal development may be disrupted by preterm birth. Hematopoietic stem and progenitor cell (CD34+) levels are poorly investigated in preterm infants, particularly in relation to immune responses and morbidities. This is partly because of low blood volumes, which raise ethical concerns and limit specific sampling for research studies. To overcome this problem, we used residual blood from routine clinical testing to monitor CD34+ cell counts in the first months of life. Our aim was to characterize the dynamics of circulating CD34+ cells and explore associations with prenatal and postnatal clinical events.
Methods:
We retrieved residual blood samples from nine infants born <28 weeks gestational age (GA), collected from birth through eight postnatal weeks. CD34+ cell count was assessed using flow cytometry. The number of nucleated red and white blood cells, and hemoglobin concentration were also measured.
Results:
Median (min-max) GA was 25+0 (22+3─27+5) weeks. CD34+ cell counts at birth ranged from 19 to 284 x 106 cells/L. Between days 0 and 1, CD34+ cell count increased in four infants and decreased in four. By day 7, the proportion of CD34+ of total nucleated blood cells was significantly lower than at birth (p=0.018). High inter- and intra-individual variability in CD34+ cell count was observed. Notably, the highest CD34+ cell levels coincided with maternal or infant infections.
Conclusion:
This pilot study demonstrates the feasibility of longitudinal monitoring of CD34+ hematopoietic stem and progenitor cells in extremely preterm infants using residual clinical blood samples. While limited by a small sample size, the study provides preliminary insights into early immune function and highlights directions for future research in larger cohorts.
