Background: The rapid and reliable identification of biomarkers in the smallest possible amount of blood remains a challenge in biomarker epidemiological research involving preterm newborns. Objective: We wanted to explore whether the proteomics approach of ‘surface-enhanced laser desorption/ionization-time of flight mass spectrometry’ (SELDI-TOF MS) is possible and feasible in whole cord blood previously dried on filter paper. Methods: Umbilical cord blood from 7 healthy newborns was frozen as serum, whole blood (with or without additives), or dried on filter paper (with or without additives). We used the SELDI-TOF MS technique for protein detection on the ProteinChip® arrays: weak cationic exchange array (CM10), hydrophobic array (H50), and strong anion exchange array (Q10). Profiles were compared in terms of peak intensity and number of resolved peaks. Results: Dried neonatal blood, eluted from filter paper, revealed profiles similar to the profiles derived from serum at a protein range of 3–10 kDa. Among additives, heparin led to highest peak intensities for both blood and dried blood. Spectra from heparinized whole blood and heparinized dried blood from the umbilical cord of 8 different healthy newborns on three different types of ProteinChip arrays were very similar. Conclusion: We conclude that it is possible and feasible to use SELDI-TOF MS for recovery and detection of whole proteins from dried blood collected on filter paper. The method is easy to perform in large groups of newborns, minimizing the amount of blood needed for biomarker studies. The validity and reproducibility of this method needs to be studied in detail.

Compared with those born at term, preterm newborns are at an increased risk of short term disorders of the lung (bronchopulmonary dysplasia; BPD) and the brain (white matter damage; WMD), and of long term developmental and pulmonary dysfunctions. Although all of these adverse outcomes are associated with low gestational age, brain, but not lung, damage appears to be associated with the prematurity subgroup [spontaneous preterm labour and/or preterm prelabour rupture of membranes (PPROM) vs pregnancy‐induced hypertension (PIH)]. Part of the association between brain damage and prematurity subgroup might be due to a differential exposure of members of these subgroups to perinatal infection/inflammation. There is a lack of studies evaluating the association of antenatal and perinatal risk factors with late childhood pulmonary dysfunction among those born during the second trimester. In this paper we discuss the complexities that paediatricians, perinatologists and perinatal epidemiologists face as they try to understand the contributions of factors associated with preterm birth to neonatal and childhood disorders.

Background: ErbB receptors, critically important for embryonic neuronal, cardiac, and lung development, are expressed in late gestation lung where they play a major role regulating the onset of surfactant synthesis (AJRCCM 167:1711 – 16, 2003). ErbB receptor ligands neuregulin (NRG) and epidermal growth factor (EGF) initiate this process. We previously showed that all four erbB receptors are expressed in both fetal lung type II cells and fibroblasts, and differ in phosphorylation and cellular response after ligand stimulation. Different erbB receptor ligands can cause diverse biologic results by stimulating specific erbB-dimers. It is not known how dimerization, cellular localization, and co-localization of dimers are regulated in fetal type II cells.

The relationships among bronchopulmonary dysplasia (BPD), brain white matter damage (WMD) and cerebral palsy (CP) are far from simple. Apparently, BPD and WMD are not associated, while BPD and CP are. The most likely explanation for this paradox is that ultrasound imaging does not identify all the WMD that might lead to CP ('tip-of-the-iceberg effect'). We discuss further methodological inconsistencies, etiological peculiarities related to antenatal infection/inflammation, and intervention-related issues. In particular, we expand on the multiple-hit scenario in the etiology of BPD and offer support for the hypothesis that it is not lung disease, but factors associated with lung disease (e.g. postnatal steroid exposure) that increase the risk for developmental disability in childhood.

Neuregulins play a critical role in the developing heart, nervous, and mammary systems. Neuregulin-1-induced cardiac, neuronal, and mammary differentiation is based on a cell-cell communication model, where the ligand neuregulin-1 is produced and secreted by one cell type, which does not express its receptors erbB3 and erbB4 and acts on neighboring cell types that do express these receptors. We proposed that neuregulin-1 affects fetal lung maturation through a similar mechanism. Immunostaining showed neuregulin-1 in fetal lung that increased in fibroblasts at the onset of surfactant synthesis. Neuregulin-1beta was found to be secreted by the fetal lung fibroblast and stimulated type II cell surfactant synthesis. Both fetal lung fibroblast-conditioned media and neuregulin-1 stimulated erbB2 receptor phosphorylation in type II cells. The effects of neuregulin-1 and of fibroblast-conditioned media on both surfactant synthesis and type II cell erbB2 phosphorylation were specifically blocked by antibody to neuregulin-1. Thus, neuregulin-1beta may control fetal lung maturation through mesenchymal-epithelial interactions in a paracrine mechanism similar to that described for the developing heart, brain, and mammary systems.

Objective: To evaluate the influence of confounding and sampling bias on the relationship between fetal growth restriction in a very-low-birthweight-defined cohort (VLBW, less than or equal to 1500 g) and bilateral spastic cerebral palsy (BSCP) at early school-age. Methods: Three hundred twenty-four of 407 long-term survivors of a regional cohort of VLBW newborns were followed until age 6 years. We categorized as small for gestational age (SGA) all infants whose birthweight Z-score was below -2 relative to published reference values. Uni- and multivariable logistic regression models were fit to estimate the risk of BSCP associated with SGA in the total sample, in subsamples defined by gestational age, and in a gestational age-matched case-control sample. Results: In the total sample, no child below 28 wet ks was SGA, and no child above 32 weeks had an appropriate birthweight for gestational age (AGA). The prevalence of BSCP was 14% in AGA and 2% in SGA infants. In both uni- sind multivariable logistic regression analyses of the total sample, SGA was associated with a prominently reduced risk of BSCP (odds ratios range from 0.1 to 0.2, all 95% confidence limits exclude 1.0). However, analyses performed in samples defined by different gestational age cutoffs (24-31 weeks, 28-31 weeks) and in a sample using three gestational age-matched controls per BSCP-case did not show a protection by growth restriction (odds ratios range from 0.8 to 2.2, all 95% confidence limits include 1.0). Conclusions: In VLBW-defined samples, the apparent protective effect of SGA for BSCP can be explained, at least in part, by the highly skewed distribution of SGA over the available gestational age range. From this follows that study cohorts should be defined by gestational age and not by birthweight. In distorted samples like this one, even controlling for gestational age does not reduce the illusion of a reduced cerebral palsy risk for growth restricted infants. Only restriction of the sample by gestational age and/or matching for gestational age reveals the absence of this apparent protective effect. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

During lung development there is tension between positive and negative regulators of fibroblast-epithelial communication controlling type II cell differentiation. A clinical consequence of imbalance of this tension is the increased risk for respiratory distress syndrome in male infants. We hypothesized that chronic intrauterine androgen exposure alters fetal lung fibroblast maturation by down-regulating epidermal growth factor receptor (EGF-R) activity and by up-regulating transforming growth factor-beta receptor (TGF beta-R) activity, leading to an inhibition of surfactant protein B (SP-B) and -C (SP-C) gene expression in type II cells. We treated pregnant mice with dihydrotestosterone (DHT; 2 mg/day) or vehicle for 7 days, starting on gestational day 11. On day 18, EGF binding, EGF-R phosphorylation, TGF beta-R binding, and TGF beta 1-induced cell proliferation were studied in sex-specific fibroblast cultures. SP-B and -C messenger RNA levels were measured in whole lungs. Chronic DHT treatment reduced both EGF binding (females to 78 +/- 8% and males to 65 +/- 9% of controls) and EGF-induced EGF-R phosphorylation. TGF beta-R binding was increased (females to 173 +/- 39% and males to 280 +/- 64% of controls), and TGF beta-induced cell proliferation was increased in female cells (231 +/- 57% ofcontrols). SP-B and -C messenger RNA expression was reduced to 55 +/- 10% and 75 +/- 4%, respectively. We conclude that chronic DHT exposure beginning early in lung development alters the balance of growth factor signaling that regulates lung maturation.

A follow-up study was conducted in 40 children who had been enrolled in a prospective randomized study of exogenous surfactant therapy for respiratory distress syndrome (RDS) (n = 22; S) or placebo (n = 18; P) to determine long-term pulmonary sequelae of surfactant treatment in premature infants with RDS. At follow-up, mean (SD) age was 6.63 (0.18) and 6.55 (0.23) years for S and P, respectively. Complete lung function tests (LFT) were attempted in all patients. Satisfactory data were obtained in 17/22 surfactant-treated and in 12/18 control children. There was no significant difference between groups for any of the parameters measured. Mean (SD) functional residual capacity (FRC) was 92% (16%) and 90% (21%) predicted, mean (SD) airway resistance (Raw,exp) was 122% (25%) and 127% (61%), and mean (SD) forced expiratory volume in 1 s (FEV1) was 104% (12%) and 99% (17%) predicted for S and P. Only maximal expiratory flow at 25% vital capacity (L/s) was significantly below the predicted range in S and P groups, with 74% (23%) and 77% (28%), respectively. To test bronchial hyperreactivity, a simple standardized running test was performed: 4 children in S and 5 in P showed a significant response as defined by clinical airway obstruction or changes in FEV1 and/or Raw, with no significant difference between groups. Although we found no major abnormalities in lung function and no difference between S and P at early school-age, lack of cooperation during lung function tests makes further follow-up necessary. Pediatr Pulmonol. 1999; 27:191–198. © 1999 Wiley-Liss, Inc.

TGF beta 1 inhibits fetal lung maturation in vitro, As TGF beta 1 is present in fetal lung, mechanisms must exist to overcome this inhibition and allow late gestation maturation to progress, We studied the ontogeny of TGF beta 1 binding, and TGF beta receptor kinetics and subtypes in primary cultures of fetal mouse lung fibroblasts from Day 16 to Day 18 of gestation. TGF beta 1 specific binding in fetal lung fibroblasts declined with advancing gestation, The decrease occurred earlier, and was more pronounced in female fibroblasts (50% decrease) than in the male fibroblasts (29% decrease). Dihydrotestosterone treatment of Day 18 female fibroblasts resulted in a dose-dependent increase in TGF beta 1 binding, Scatchard analysis revealed a decline in receptor number with advancing gestation (Day 16 female B-max: 7.3 x 10(-16) Day 18 female B-max: 5.5 x 10(-16)) whereas binding affinities remained constant. Affinity labeling followed by chemical cross-linking and autoradiography showed the three known TGF beta receptor subtypes at both Days 16 and 18 of gestation. The relative abundance of nonsignaling Type III receptors in comparison to signaling Type II and Type I receptors was increased at Day 18 versus Day 16, Incorporation of [H-3]thymidine into DNA lifter treatment with TGF beta 1 changed from Day 16 to Day 18, consistent with changes previously reported between fetal and adult lung fibroblasts. We conclude that a!; fetal mouse lung maturation progresses, TGF beta receptor number decreases in fibroblasts, the relative proportion of nonsignaling versus signaling receptor types increases, and the response to TGF beta 1 stimulation changes, These changes may contribute! to overcoming TGF beta 1 inhibition of lung maturation.