Effects of granulocyte colony-stimulating factor on neutrophil adhesive molecules in neonates

Background: Term and preterm neonates experience quantitative and qualitati ve neutrophil deficiencies resulting in part from decreased production of g ranulocyte colony-stimulating factor (G-CSF). In adults, G-CSF improves neu trophil function by upregulating adhesion molecules. Patients and Methods: To evaluate the effects of G-CSF on neonatal neutroph il adhesive phenotypes, cord blood samples were incubated with G-CSF or pho sphate-buffered saline and stimulated With N-formyl-methionyl-leucyl-phenyl alanine (FMLP), and adhesion molecules were evaluated by flow cytometry. Results: In term and preterm neutrophils, G-CSF incubation increased P.-int egrin expression significantly compared with baseline and to a greater exte nt than observed in adult neutrophils. With FMLP stimulation, beta (2)-inte grin expression increased even more in the G-CSF group. L-selectin expressi on decreased after G-CSF incubation and decreased even more with FMLP stimu lation in the G-CSF group compared with the phosphate-buffered saline group in term and preterm samples, but not in adult samples. Conclusions: The data show that G-CSF increases expression of beta (2)-inte grin and decreases expression Of L-selectin on unstimulated and stimulated term and preterm. neonatal neutrophils in vitro. Further study is required to determine whether G-CSF improves neonatal neutrophil function.