ABSTRACT
Neutrophil production and functions are immature in newborns. Although neutrophil
kinetics during neonatal period have been widely studied, little is known about the
effect of apoptosis on these defects. In this study, we examine the apoptosis of neonatal
neutrophils and the effects of colony-stimulating factors (CSF) on this process. The
study was performed using three different methodologies (morphological analysis, surface
Fas expression, and mitochondrial 7A6 antigen expression) and the results were compared
with adult controls. Neonatal neutrophils more rapidly underwent apoptosis in comparison
to adult neutrophils. The above-mentioned three different methods gave similar results.
Granulocyte-CSF (G-CSF) and granulocyte-macrophage CSF (GM-CSF) decreased the apoptosis
of neutrophils in newborns and adults. This effect was significantly more pronounced
in adults than newborns in morphological analysis. Increased apoptosis may contribute
to qualitative and quantitative defects of neutrophils during neonatal period and
may be an explanation for the proneness of newborn to develop neutropenia during systemic
infections.
KEYWORD
Cord blood neutrophil - apoptosis - colony-stimulating factor
