Myeloid hematopoietic growth factors and their role in prevention and/or treatment of neonatal sepsis.

Sepsis continues to be an important cause of morbidity and mortality among both full-term and preterm infants, secondary to an immaturity in neonatal host defense. The incidence of neonatal sepsis ranges from 30% in very low birth weight infants to 0.4% in preterm neonates and 0.1% in term neonates. The dysregulation of the expression and production of hematopoietic cytokines in the neonate contributes to quantitative and qualitative deficiencies in neonatal myeloid progenitor activity and decreased availability and function of mature effector neutrophils. These abnormalities contribute in large part to the increased incidence and mortality associated with neonatal sepsis. In this review, we have summarized and analyzed the studies investigating the dysregulation, expression and production of myelopoietic growth factors in neonates, the preclinical in vivo effects of myelopoietic growth factors in neonatal animals, the preclinical in vivo effects of myelopoietic growth factors during experimental sepsis in neonatal animals, the in vitro effects of growth factors on human neonatal phagocytic immunity, and clinical results of myelopoietic growth factors in human neonates. Future studies should be focused on investigating other abnormalities of neonatal host defense and multiple and simultaneous approaches to circumvent identified defects to attempt to reduce both the incidence and severity of neonatal host defense.