Altered gene expression in umbilical cord mononuclear cells in preterm infants with periventricular leukomalacia

Abstract

Aim Periventricular leukomalacia (PVL) is one of the most important causes of adverse outcome of preterm infants. We hypothesized that inflammatory or some other specific pathways will have been activated at birth in preterm infants who later develop PVL. The aim of this study is to examine the difference in mRNA expression in umbilical cord blood according to the presence or absence of PVL. Methods A total of 61 umbilical cord blood samples were collected from preterm infants with gestational age less than 33 weeks together with the patients' medical information during perinatal period. RNA expression patterns in the collected cord bloods were analyzed by microarray. On the basis of cranial ultrasonography and brain MRI examination, 3 infants (4.9%) were diagnosed as cystic PVL and selected as the subjects. Five patients who showed similar perinatal factors to those of infants with PVL but did not show PVL were selected as the normal control. Results Five of the 15 up-regulated genes are coding ribosomal proteins, and another encodes a translation elongation factor. Three of the 7 down-regulated genes encode proteins that may be related to immune response and/or inflammation. Conclusions Up-regulation of the ribosomal proteins may indicate an activation of lymphocytes during the fetal period.