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Premature infants, especially those with bronchopulmonary dysplasia (BPD), develop recurrent severe respiratory viral illnesses. We have shown that hyperoxic exposure of immature mice, a model of BPD, increases lung IL-12-producing Clec9a + CD103 + dendritic cells (DCs), pro-inflammatory responses, and airway hyperreactivity following rhinovirus (RV) infection. However, the requirement for CD103 + DCs and Clec9a, a DAMP receptor that binds necrotic cell cytoskeletal filamentous actin (F-actin), for RV-induced inflammatory responses has not been demonstrated. To test this, 2-day-old C57BL/6J, CD103 + DC-deficient Batf3 -/- or Clec9a gfp-/- mice were exposed to normoxia or hyperoxia for 14 days. Also, selected mice were treated with neutralizing antibody against CD103. Immediately after hyperoxia, the mice were inoculated with RV intranasally. We found that compared with wild-type mice, hyperoxia-exposed Batf3 -/- mice showed reduced levels of IL-12p40, IFN-γ, and TNF-α, fewer IFN-γ-producing CD4 + T cells, and decreased airway responsiveness following RV infection. Similar effects were observed in anti-CD103-treated and Clec9a gfp-/- mice. Furthermore, hyperoxia increased airway dead cell number and extracellular F-actin levels. Finally, studies in preterm infants with respiratory distress syndrome showed that tracheal aspirate CLEC9A expression positively correlated with IL12B expression, consistent with the notion that CLEC9A + cells are responsible for IL-12 production in humans as well as mice. We conclude that CD103 + DCs and Clec9a are required for hyperoxia-induced pro-inflammatory responses to RV infection. In premature infants, Clec9a-mediated activation of CD103 + DCs may promote pro-inflammatory responses to viral infection, thereby driving respiratory morbidity.

This study aimed to explore the clinical efficacy of pulmonary surfactant combined with high-frequency oscillatory ventilation (HFOV) on neonatal respiratory distress syndrome (NRDS) and its influence on immune function in children. Children admitted to our hospital from March 2017 to March 2019 who received HFOV combined with pulmonary surfactant therapy as a research group. Sixty-two children received conventional nasal continuous positive pressure combined with pulmonary surfactant therapy as a control group. Clinical efficacy, blood gas and immune function of patients were compared between the two groups. The clinical efficacy of the research group was better than that of the control group (P< 0.050). PaO2 and PaO2/FiO2 were both higher after treatment (P< 0.050). CD3+ and NK cells in the research group were higher than those in the control group, while CD8+ cells and ICAM-1 were lower than those in the control group (P< 0.050). CD3+, CD4+ and NK cells decreased in both groups after treatment, while CD8+ cells and ICAM-1 increased (P< 0.050). HFOV combined with pulmonary surfactant has significant clinical efficacy and high safety on NRDS, and has a certain protective effect on children's immune function. Hence, it is worthy of being the first choice for the clinical treatment of NRDS in the future.

Introduction: Preeclampsia complicates about 10-17 % of pregnancies with antiphospholipid syndrome (APS). It is often severe and might occur sometimes at early gestation. The development of preeclampsia before fetal viability is a huge challenge for obstetricians and demands an intensive discussion regarding the therapeutical options., Patients and Methods: We retrospectively reviewed the data of 7 women with primary APS who developed preeclampsia before 24 weeks of gestation. Plasma exchange had been performed in four of the cases and two women received corticosteroids. One of the women had received 20 mg of pravastatin daily, starting at 18 weeks of gestation. Neonatal outcome was: live birth in four cases and IUFD in three cases. The main pediatric complications were noted in a 28-week-old premature born boy, who developed severe IRDS and thrombocytopenia. At the present time, the boy continues to have a retarded status., Discussion: This retrospective analysis revealed that women with APS can develop severe preeclampsia even before 20 weeks of gestation. Several management options for prolongation of pregnancy such as plasma exchange, pravastatin, LMHW, hydroxychloroquine/HCQ, or TNF-alpha blocker should be discussed with the patients. Optimal management of preeclampsia before 24 weeks of gestation usually depends on weighing the maternal and fetal complications from expectant management with prolongation of pregnancy versus the predominant fetal and neonatal risks of extreme prematurity from "aggressive" management with immediate delivery., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

BACKGROUND Acute respiratory distress syndrome (ARDS) is a sudden and serious disease with increasing morbidity and mortality rates. Phosphodiesterase 4 (PDE4) is a novel target for inflammatory disease, and ibudilast (IBU), a PDE4 inhibitor, inhibits inflammatory response. Our study investigated the effect of IBU on the pathogenesis of neonatal ARDS and the underlying mechanism related to it. MATERIAL AND METHODS Western blotting was performed to analyze the expression levels of PDE4, CXCR4, SDF-1, CXCR5, CXCL1, inflammatory cytokines, and proteins related to cell apoptosis. Hematoxylin-eosin staining was performed to observe the pathological morphology of lung tissue. Pulmonary edema score was used to assess the degree of lung water accumulation after pulmonary injury. Enzyme-linked immunosorbent assay (ELISA) was used to assess levels of inflammatory factors (TNF-alpha, IL-1ß, IL-6, and MCP-1) in serum. TUNEL assay was used to detect apoptotic cells. RESULTS Increased expression of PDE4 was observed in an LPS-induced neonatal ARDS mouse model, and IBU ameliorated LPS-induced pathological manifestations and pulmonary edema in lung tissue. In addition, IBU attenuated the secretion of inflammatory cytokines by inactivating the chemokine axis in the LPS-induced neonatal ARDS mouse model. Finally, IBU significantly reduced LPS-induced cell apoptosis in lung tissue. CONCLUSIONS IBU, a PDE4 inhibitor, protected against ARDS by interfering with pulmonary inflammation and apoptosis. Our findings provide a novel and promising strategy to regulate pulmonary inflammation in ARDS.

BACKGROUND Neonatal acute respiratory distress syndrome (ARDS) is a common clinical syndrome caused by lung immaturity and the abnormal synthesis of pulmonary surfactant in preterm newborns, and it has high morbidity and mortality rates. The present study investigated the roles of interleukin-37 (IL-37) in the pathogenesis of neonatal ARDS and the underlying biochemical mechanism. MATERIAL AND METHODS We used 6-day-old neonatal C57BL/6 mice to establish the ARDS model. Inflammatory cytokines levels were measured with enzyme-linked immunosorbent assay (ELISA) Kits. The pathological morphology of lung tissues was observed by hematoxylin-eosin (HE) staining. The expression levels of proteins were assessed by Western blotting and apoptotic cells were detected via TUNEL assay. Further, the expression of nucleotide-bound oligomerization domain (Nod)-like receptor P3 (NLRP3) was detected with immunohistochemistry and Western blotting. RESULTS IL-37 attenuated lipopolysaccharide (LPS)-induced cell apoptosis and excessive inflammatory cytokines levels, including IL-1ß, IL-8, TNF-alpha, and MCP-1, and ameliorated lung pathological manifestations in an LPS-induced neonatal ARDS model. Moreover, IL-37 suppressed the abnormal expression of proteins related to the CXCR4/SDF-1 chemokine axis and NLRP3 inflammasome pathway. CONCLUSIONS The present results suggest that IL-37 protect against LPS-induced lung injury through inhibition of inflammation and apoptosis in lung tissue in an LPS-induced neonatal ARDS model. Hence, IL-37 may be considered as a potential therapeutic agent for neonatal ARDS.

Objective:   Micro ribonucleic acids (miRNAs) are crucial to post-transcriptional regulation of the gene expression. Whether miR-26a affects respiratory distress syndrome (RDS) in neonatal rats through the Wnt/β-catenin signaling pathway was investigated in this study., Patients and Methods: The neonatal rat model of RDS was established, and the expressions of miR-26a and glycogen synthase kinase-3β (GSK-3β) in RDS in neonatal rats and their correlation were analyzed. The cascade relationship between miR-26a and the Wnt/β-catenin signaling pathway and the influence of miR-26a on the expression of inflammatory cytokines were subsequently verified. Finally, the influences of miR-26a on the expressions of important markers, receptor for advanced glycation endproducts (RAGE), high mobility group box 1 (HMGB1), and plasminogen activator inhibitor-1 (PAI-1), through the Wnt/β-catenin signaling pathway were analyzed., Results: Compared with those in normal tissues, the expression of miR-26a in lung tissues of neonatal rats with RDS was significantly decreased (p<0.05), while the expression of GSK-3β messenger RNAs (mRNAs) was notably increased (p<0.01), and the GSK-3β expression was negatively correlated with the miR-26a expression (r=-0.6693, p=0.0064). In addition, miR-26a mimics significantly inhibited the GSK-3β protein expression and activated the Wnt/β-catenin signaling pathway. Moreover, miR-26a could reduce the expressions of tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6, as well as RAGE, HMGB1, and PAI-1., Conclusions: MiR-26a can affect inflammatory responses and markers through the Wnt/β-catenin signaling pathway in neonatal rats with RDS.

Ventilator-induced lung injury is well recognized, and appropriate arterial saturation target is unknown, so gentle modes of ventilation and minimizing oxidative stress have been well studied. Our objective was to analyze any association between the oxygen levels at blood sampling and plasma levels of the interleukins IL-6, IL-1 β , IL-10, and IL-8 and TNF- α in preterm newborns under mechanical ventilation (MV) in their first two days. Methods . Prospective cohort including neonates with severe respiratory distress. Blood samples were collected right before and 2 hours after invasive MV. For analysis purposes, newborns were separated according to oxygen requirement: low oxygen (≤30%) and high oxygen (>30%) groups. Interleukins were measured using a commercially available kit. Results . 20 neonates (gestational age 32.2 ± 3 weeks) were evaluated. Median O 2 saturation levels pre-MV were not different in both oxygen groups. In the high oxygen group, IL-6, IL-8, and TNF- α plasma levels increased significantly after two hours under MV. Conclusions . Despite the small sample studied, data showed that there is a relationship between VILI, proinflammatory cytokines, and oxygen-induced lung injury, but a study considering oxidative marker measurements is needed. It seems that less oxygen may keep safer saturation targets playing a less harmful role.

CHARGE (coloboma, heart defect, atresia choanae, retarded growth and development, genital hypoplasia, and ear anomalies/deafness) syndrome is a rare genetic disorder caused by CHD7 mutation and is related to immunodeficiency. A 6-month-old girl with right lung agenesis, congenital heart defects, and ear anomalies developed repeated and serious respiratory infection for a short period. She was clinically diagnosed with typical CHARGE syndrome with severe combined immunodeficiency (T-, B+, NK-); however, CHD7 mutation was not detected. Disseminated BCG infection did not resolve despite administration of anti-tuberculosis drugs and intravenous immune globulins, and she subsequently died of acute respiratory distress syndrome. Pediatr Pulmonol. 2017;52:E4-E6. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Gene-environment interactions likely account for some degree of the variance in response rates that are clinically observed with antenatal corticosteroids, breast milk prophylaxis, surfactant administration, early recognition and treatment of sepsis, utility of non-invasive ventilation, and judicious exposure to supplemental oxygen. While these therapies and practice guidelines have significantly decreased overall neonatal mortality in the NICU, they have not made a marked impact on the frequency and severity of conditions such as bronchopulmonary dysplasia (BPD), necrotizing enterocolitis, and periventricular leukomalacia. One possible explanation is that genetic factors in the neonate modulate response to external intervention or preventative agents, culminating in variable levels of injury and different degrees of resolution and repair. Gene-environment explanations are supported by the observed heritability of BPD in twin studies, but they do not differentiate the interactions between neonate and offending toxin or pathogen, from interactions between neonate and intervention or therapeutic agent. Likely, both kinds of interactions are important in determining outcome., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Aims: The risk of neonates for severe infection/sepsis is reciprocally proportional to gestational age and birth weight. As monocytes and dendritic cells (DC) are recognised key antigen-presenting immune cells, we aimed to elucidate whether neonatal age is associated with reduced expression of human-leukocyte antigen-DR (HLA-DR) antigens on subsets of monocytes and DCs., Methods: Forty-three consecutive neonates (20 male, mean gestational age 236.0±26.8 days; mean 1-min Apgar score 7.5±2.0) were included in a monocentric prospective observational analysis. Patients were grouped according to gestational age (n=15 full-term, n=28 pre-term defined as <33 weeks). Ten healthy adult volunteers were assessed also. Flow-cytometric assessment of HLA-DR expression was performed in subsets of peripheral blood myeloid and plasmacytoid DCs (MDC and PDC) and monocytes (CD14brightCD16negative/CD14positiveCD16positive/CD14dimCD16positive). Clinical and routine laboratory data were followed up., Results: At birth, leukocyte counts were increased in full-term neonates. Monocyte counts were significantly increased in neonates when compared with adults (all P<0.05). A significant numerical increase of CD14brightCD16negative and CD14positiveCD16positive monocytes was noted in pre-term and full-term neonates (all P<0.05), while HLA-DR expression in these subsets was significantly diminished (most pronounced in pre-term infants, P<0.0001). MDC and PDC HLA-DR expression was reduced also (all P<0.05). Clinical indices (e.g., pH, days on antibiotics/mechanical ventilation, fever/sepsis) were not found to correlate with immunological indices., Conclusions: We observed a markedly diminished HLA-DR expression on monocyte and DC subsets in pre-term and full-term neonates, which may contribute to impaired antimicrobial defence mechanisms in the early days of life.

Unlabelled: Infant respiratory distress syndrome (iRDS) in babies born from women with intrahepatic cholestasis of pregnancy (ICP) has been associated with intrauterine exposure to high bile acid levels. Here, we have investigated the role of macrophages in hypercholanemia-induced changes in maternal and fetal lung. Obstructive cholestasis in pregnant rats (OCP) was maintained from day 14 of gestation to term. Gene expression was determined by RT-QPCR, Western blot, and immunofluorescence. The maternal-fetal bile acid pool was radiolabelled using [(3)H]-taurocholate. OCP resulted in increased bile acids in maternal and fetal organs, including lungs. This was accompanied by structural changes in lung tissue, more marked in fetuses (peribronchial edema, collapse of alveolar spaces and deposits of hyaline material in the alveolar lumen), and infiltration of lung tissue by inflammatory cells. The abundance of macrophages and neutrophils in bronchoalveolar lavage fluid (BALF) was also increased in OCP group. Phospholipase A2-IIA (PLA2), the key enzyme in surfactant degradation, was mainly immunodetected in macrophages, which also expressed the bile acid receptor TGR5. The overall expression of PLA2 was markedly enhanced in maternal and fetal lungs of OCP group and in control maternal BALF cells incubated with bile acids. In neonates born from OCP mothers, the enhanced expression of erythropoietin suggested the presence of hypoxia due to iRDS. In conclusion, these results indicate that the accumulation of bile acids due to maternal cholestasis triggers an inflammatory response in the maternal and fetal lungs together with enhanced macrophage-associated PLA2 expression, which may play an important role in iRDS development., Key Messages: Maternal cholestasis causes respiratory distress syndrome in rat neonates. Cholestasis in pregnant rats causes bile acid accumulation in the fetal lung. This induces lung macrophages infiltration and inflammatory response. Alveolar macrophages co-express phospholipase A2-IIA and TGR5, but not FXR. Bile acid accumulation stimulates phospholipase A2-IIA, but not TGR5, expression.

Background: As a protective response to an inflammatory stimulus, the antigen-presenting molecules (human leukocyte antigen-DR (HLA-DR)) on monocytes are downregulated. If severe, the response may lead to immunodepression or immunoparalysis, associated with an increased rate of morbidity and mortality in adults. In very low birth weight (VLBW) infants, birth and intensive care present major immunological challenges., Methods: We measured monocyte HLA-DR expression by flow cytometry and determined 13 plasma cytokines in 56 VLBW infants (gestational age (GA): 23.7-31.8 wk) and 25 controls (GA: 34.1-41.4 wk)., Results: HLA-DR expression decreased postnatally both in VLBW and in control infants. In VLBW infants, GA and respiratory distress syndrome (RDS) both showed associations with HLA-DR nadir on day 3, when 45% of them met the criteria of immunodepression. HLA-DR expression was lower in those infants subsequently developing infection (74 vs. 49% (day 3) and 85 vs. 68% (day 7); both P = 0.002). Interleukin (IL)-6 on day 1 was a predictor of the HLA-DR nadir., Conclusion: VLBW infants are in a state of immunodepression postnatally. This immunodepression correlated with GA and was a predisposing factor for late infections. The downregulation of HLA-DR during RDS probably indicates an RDS-induced antigen load on the immune system.

Objective: To investigate the effect of pulmonary surfactant (PS) on the Th1/Th2 balance and serum levels of interleukin-4 (IL-4), interferon-γ (IFN-γ) and IgE in neonates with respiratory distress syndrome (RDS)., Methods: A total of 58 neonates with RDS were divided into control (n=20) and PS treatment groups (n=38). The control group underwent mechanical ventilation and other conventional treatment, while the PS treatment group received with bovine PS treatment within 1 hour of being admitted to the hospital together with mechanical ventilation and other conventional treatment. Enzyme-linked immunosorbent assay was used to measure serum levels of IL-4, IFN-γ and IgE before treatment and 24, 48 and 72 hours after treatment. Simultaneously, arterial blood gas, respiratory system compliance, and other ventilator parameters were recorded., Results: Compared with the control group, the PS treatment group showed significantly shorter duration of mechanical ventilation and oxygen exposure time (P<0.05), significantly better respiratory system compliance and significantly lower oxygenation index 24, 48 and 72 hours after treatment (P<0.05). At 48 and 72 hours after treatment, serum levels of IFN-γ were significantly lower in the PS treatment group than in the control group (120±46 ng/L vs 229±59 ng/L, P<0.05; 141±40 ng/L vs 282±44 ng/L, P<0.05), and serum levels of IL-4 were significantly higher in the PS treatment group than in the control group (263±48 pg/mL vs 152±45 pg/mL, P<0.05; 417±49 pg/mL vs 201±46 pg/mL, P<0.05). At 72 hours after treatment, serum level of IgE was significantly lower in the PS treatment group than in the control group (115±44 pg/mL vs 199±43 ng/mL; P<0.05)., Conclusions: PS treatment can shorten the duration of mechanical ventilation and oxygen exposure time, regulate serum levels of IFN-γ, IL-4 and IgE, and influence Th1/Th2 balance in neonates with RDS, thus inhibiting lung inflammatory response and reducing lung injury.

Objectives: To evaluate the clinical significance of Ureaplasma urealyticum recovery from umbilical cord blood, using Polymerase Chain Reaction (PCR), and its association with umbilical cord interleukin-6 (IL-6) levels and neonatal morbidity in preterm infants., Methods: Cord blood PCR for Ureaplasma urealyticum, and IL-6 were assessed in relation to neonatal outcomes of 30 preterm deliveries of less than 35 weeks' gestation., Results: Ureaplasma urealyticum was present in 43.3% of the examined cord blood samples. Positive neonatal Ureaplasma urealyticum was more common in association with premature rupture of membranes, chorioamnionitis, antenatal maternal use of antibiotics, and earlier gestation. Ureaplasma urealyticum was also associated with an early pro-inflammatory immune response (i.e. elevated IL-6 and positive C-reactive protein). Cutoff level of interleukin-6 of 240 pg% predicts the occurrence of respiratory distress syndrome (RDS), in neonates with positive PCR for Ureaplasma urealyticum., Conclusions: Preterm patients with positive cord blood PCR for Ureaplasma urealyticum were more likely to have premature rupture of membrane, antenatal antibiotics, chorioamnionitis, earlier gestation, pro-inflammatory response, and RDS than those with a negative PCR. High IL-6 is more likely associated with RDS in Ureaplasma urealyticum positive neonates.

Background: As compared with constant respiratory rate (RR) and tidal volume (V(T)) during controlled conventional mechanical ventilation (CV), variable ventilation (VV) using the same breath-to-breath minute volume but variable V(T) and RRs enhances ventilation efficiency in preterm lambs. We hypothesized that if V(T) was adjusted to target permissive hypercarbia, VV would result in more efficient gas exchange without increasing inflammatory and injurious responses in the lung., Methods: Preterm lambs at 129 d gestation were anesthetized, tracheotomized, and randomized to either CV (n = 8) or VV (n = 8) using the same initial average V(T) and RR. Lung mechanics and gas exchange were measured intermittently, and average V(T) was adjusted to target partial pressure of arterial carbon dioxide (PaCO2) of 40-50 mm Hg for 3 h. Lung injury and inflammation were assessed from bronchoalveolar lavage fluid, lung tissue, and peripheral blood., Results: VV achieved permissive hypercarbia using a lower average V(T), peak inspiratory pressure, and elastance (increased compliance) as compared with CV. Oxygenation and markers of lung tissue inflammation or injury were not different apart from a lower wet:dry tissue ratio in the VV lungs., Conclusions: VV improves ventilation efficiency and in vivo lung compliance in the ovine preterm lung without increasing lung inflammation or lung injury.

Background: Acute inflammatory responses to supplemental oxygen and mechanical ventilation have been implicated in the pathophysiological sequelae of respiratory distress syndrome (RDS). Although surfactant replacement therapy (SRT) has contributed to lung stability, the effect on lung inflammation is inconclusive. Lucinactant contains sinapultide (KL4), a novel synthetic peptide that functionally mimics surfactant protein B, a protein with anti-inflammatory properties. We tested the hypothesis that lucinactant may modulate lung inflammatory response to mechanical ventilation in the management of RDS and may confer greater protection than animal-derived surfactants., Methods: Preterm lambs (126.8 ± 0.2 SD d gestation) were randomized to receive lucinactant, poractant alfa, beractant, or no surfactant and studied for 4 h. Gas exchange and pulmonary function were assessed serially. Lung inflammation biomarkers and lung histology were assessed at termination., Results: SRT improved lung compliance relative to no SRT without significant difference between SRT groups. Lucinactant attenuated lung and systemic inflammatory response, supported oxygenation at lower ventilatory requirements, and preserved lung structural integrity to a greater degree than either no SRT or SRT with poractant alfa or beractant., Conclusion: These data suggest that early intervention with lucinactant may more effectively mitigate pulmonary pathophysiological sequelae of RDS than the animal-derived surfactants poractant alfa or beractant.

Respiratory distress syndrome (RDS) is a common problem and the leading cause of death in premature infants (PI). The introduction of surfactant treatment for RDS management has lowered mortality and morbidity; nevertheless, some neonates do not improve and are at increased risk of pulmonary hemorrhage. Inflammation, not only local but also systemic, seems to play an important role in the pathogenesis of RDS. To determine whether cytokine patterns characterize RDS and its outcome, we measured type-1 (IL-2, TNF-α, IFN-γ, IL-6) and type-2 (IL-4, IL-5, IL-10, TGF-β1) serum cytokines of 47 PI with established RDS and a control group of 30 healthy, appropriate for gestational age, full-term neonates. Cord blood samples were obtained at the time of delivery from PI and controls. Venous blood samples were collected from PI who received surfactant treatment and/or developed pulmonary hemorrhage. Significantly elevated cord blood cytokine levels were observed in PI at time of delivery, compared to controls, except for IL-5 and TNF-α levels that were within control range. The type-1/type-2 cytokine ratio was significantly increased in PI vs controls. Neonates who developed pulmonary hemorrhage between 2 and 3 days of life and/or died, presented the strongest Th1 and type-1 cytokine polarization that was mainly due to increased IFN-γ and TNF-α, and decreased TGF-β1. The majority of these PI were female with very low gestational age. Overall, PI with RDS present a Th1/type-1 cytokine polarization, which persists irrespective of the treatment provided, and is amplified when complications appear. Th1 polarization is associated with poor prognosis., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Immaturity of the pulmonary and immune systems represents an important risk factor for increased morbidity and mortality in neonates. Surfactant protein (SP)-A and SP-D, linking molecules between these two systems, are critical for lung homeostasis as they regulate surfactant metabolism and host immunodefense activities in innate and adaptive immunity. Preterm neonates with respiratory distress syndrome showed lower concentrations of SP-A and SP-D, and the administration of exogenous surfactant was found to strengthen the secretion of SPs. Low levels of SP-A and SP-D also correlated with a higher risk of infection and development of bronchopulmonary dysplasia. Moreover, SP-A- and SP-D-enriched surfactant formulations were more resistant to the inhibitory action of the plasmatic proteins in animal models. Based on these assumptions, new-generation surfactants, enriched with SP-A and/or SP-D, may enhance the function of immune system and lungs in neonates, potentially improving the clinical outcome.

Background: Intrapartum colonization with Streptococcus pneumoniae (S. pneumoniae) is a rare but important risk factor for severe courses of early-onset sepsis (EOS) in the newborn, as underlined in the case of a preterm infant born after 32 weeks of gestation described here. One potential explanation could be an immature immune response of the neonate to S. pneumoniae, however, immunological data in term and preterm infants are scarce., Methods: To determine the neonatal immune responses to S. pneumoniae, flow-cytometry analysis of the cytokine production by CD14+ cells was performed after full pathogen stimulation with S. pneumoniae (serotype 18C, derived from an EOS case described here) of cord blood of 10 term (37-41 gestational weeks) and 6 preterm (31-32 gestational weeks) neonates, compared to peripheral venous blood samples of 10 healthy adults in vitro., Results: Neonatal cytokine responses of term and preterm infants to S. pneumoniae are diminished compared to adults. The quantities of cytokine expression were comparable to immune responses induced by other important gram-positive pathogens of EOS such as Streptococcus agalacticae., Conclusion: Severe courses of EOS with S. pneumoniae may be attributed to remarkable deficiencies of the specific neonatal immune response. To protect the neonate from invasive pneumococcal disease, maternal immunization may be an important prevention strategy, as protective antibodies can be transferred through the placenta and vaccination of pregnant women may reduce colonization.

We studied the role of ante- and post-natal infection in the development of chronic lung disease (CLD) of prematurity. 192 newborn infants (61 term and 131 pre-term of <34 weeks gestation: 88 with respiratory distress syndrome, 35 developed CLD and eight died) were recruited. 16S ribosomal RNA (rRNA) genes were identified by PCR of DNA isolated from 840 gastric and lung fluid samples. Ureaplasma spp. were also cultured. Presence of 16S rRNA genes (OR 1.6, 95% CI 1.2-2.2) and Ureaplasma spp. (OR 3.6, 95% CI 1.7-7.7) was significantly associated with the development of CLD. This association remained if the 16S rRNA genes and Ureaplasma spp. were first identified within the first 3 days of life (OR 2.4 (95% CI 1.4-4.1) and 3.8 (95% CI 1.4-10.0), respectively) or if first identified after 3 days of age (OR 1.7 (95% CI 1.1-2.8) and OR 5.1 (95% CI 1.3-19.8), respectively). Peak lung fluid interleukin (IL)-6 and IL-8 were significantly associated with presence of microbes (p<0.0001 and p=0.0001, respectively) and development of CLD (p=0.003 and 0.001, respectively). Both early and late microbial presence in neonatal lung fluid samples was significantly associated with the development of CLD suggesting that both ante- and post-natal infection play a role in the development of CLD.

Adenosine is produced in the inflammed and damaged lung where it plays roles in the regulation of inflammation and tissue remodeling. Adenosine deaminase (ADA) is an enzyme responsible for the degradation of adenosine. Our aim was to compare the levels of ADA between infants with and without respiratory distress syndrome (RDS) and to determine the relationship between plasma ADA levels and bronchopulmonary dysplasia (BPD). One-hundred and twenty-five premature infants who were admitted to our neonatal intensive care unit were included in the study. Eighty-one of these infants with RDS were study group and the other 44 infants without RDS served as controls. Blood collection was made in the first day of life at the end of 24th-h and was used for laboratory testing. In the RDS group, mean ADA level was 25.5 (± 4.5) U/l, and in controls it was 26.3 (± 5.7) U/l. There was no statistically significant difference (p = 0.326) in these groups although there was a statistically difference of ADA levels between BPD (34.5 ± 5.2 U/l) and non-BPD (24.6 ± 4.1) patients (p = 0.001). There was also a positive relationship between ADA levels and severity of BPD (r = + 0.845, p = 0.01). Perinatal inflammation is the key mechanism of BPD. ADA level in early postnatal life is elevated in infants with BPD and may be related with perinatal inflammation.

Objectives: Fetal lung maturation and respiratory outcomes are influenced by the exposure to intrauterine inflammation. Funisitis is considered as the histologic hallmark of fetal inflammatory response. This study was performed to determine if there is a difference in the rate of neonatal respiratory distress syndrome (RDS) according to the presence or absence of funisitis in preterm gestations., Study Design: The relationship between the presence of funisitis and the development of neonatal RDS was examined in 301 consecutive singleton preterm births (24-32 weeks' gestation). Cases without placental histological examination and those with major congenital anomalies were excluded. Funisitis was diagnosed in the presence of neutrophil infiltration into the umbilical vessel walls or Wharton's jelly on the placental histological examination., Results: Funisitis was diagnosed in 25% and RDS was diagnosed in 46% of cases. The rate of RDS in babies with funisitis was lower than in those without funisitis (28.4% vs. 51.1%, p = 0.001). Logistic regression analysis demonstrated that the presence of funisitis was associated with a decreased risk for RDS after adjusting for confounding variables (Odds ratio = 0.44, 95% CI 0.22-0.90). The downward trend of the frequency of RDS was related to the presence of histologic chorioamnionitis and funisitis (p < 0.001)., Conclusions: The presence of funisitis is associated with a decreased risk for the development of neonatal RDS in preterm gestations. Furthermore, this observation suggests that the fetal involvement of placental inflammation may be beneficial to the maturation of the fetal lung., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Objective: Clara cell 16 kD protein (CC16) and interleukin (IL)-6 have been used as peripheral blood biomarkers of alveolar leakage and inflammation, respectively. Thus, their measurement in the bloodstream could be used to assess ventilator-induced lung injury. The objective of this study was to evaluate the effect of optimized synchronized intermittent mandatory ventilation (SIMV) and high-frequency oscillatory ventilation (HFOV) on circulating CC16 and IL-6 levels when used as the initial ventilation modes in preterm neonates., Study Design: Single center, prospective, randomized clinical study in preterm neonates (gestational age 30 weeks) requiring mechanical ventilation within the first 2 h of life. Serum CC16 and IL-6 were measured on establishment of the assigned ventilation mode after admission, at days 3 and 14 of life as well as at 36 weeks postmenstrual age. Demographic-perinatal data and clinical parameters were also recorded., Result: Of the 30 neonates studied, 24 (gestational age 27.1±1.7 weeks, birth weight 942±214 g) were finally analyzed, equally assigned into the SIMV and HFOV groups. Both groups had comparable demographic-perinatal characteristics and clinical parameters. Serum CC16 and IL-6 altered significantly over time (repeated-measures analysis of variance, both P<0.001). However, changes were not affected by the ventilation mode. Post hoc analysis showed a significant decrease in CC16 and IL-6 from birth up to 36 weeks postmenstrual age in both groups., Conclusion: In preterm neonates, SIMV and HFOV are associated with comparable circulating CC16 and IL-6 levels. These findings suggest a similar alveolar leakage and systemic inflammation with any of the ventilation modes evaluated when their usage is optimized.

Objectives: The objective of the paper was to determine whether circulating stem-progenitor cells were elevated along with its mobilizing cytokines in neonatal respiratory distress syndrome (RDS)., Subjects and Methods: Circulating CD34(+) cells were identified by flow cytometry in 41 RDS in comparison with 20 preterm and 14 term controls without diffuse lung diseases. Plasma concentrations of vascular endothelial growth factor, stromal cell-derived factor-1 (SDF-1) and granulocyte-macrophage colony-stimulating factor were determined by immunochemical assays., Results: The number of CD34(+) cells was significantly higher in RDS [25(6-174) cells/microl] than in the preterm controls [15(1-100) cells/microl, P < 0.05]. RDS survivors had higher level of CD34(+) cells than non-survivors (P < 0.05), and low CD34(+) cell level in RDS was correlated with prolonged duration of ventilation (r = -0.396, P < 0.05). Likewise, the CD34(+) cell level was inversely associated with Score for Neonatal Acute Physiology Perinatal Extension II (r = -0.473, P < 0.01) in RDS. Plasma SDF-1 concentration was significantly higher in RDS than in the preterm controls (P < 0.01), and was correlated with the level of CD34(+) cells (r = 0.305, P < 0.01)., Conclusions: The level of circulating CD34(+) cells was elevated in RDS along with an increase of plasma SDF-1, suggesting CD34(+) cells might be involved in reparation of neonatal lung injury.

Preterm and young neonates have an increased predisposition to respiratory distress syndrome (RDS) associated with an immature development of lung surfactant. Glucocorticoids (GCs) are the major immunomodulatory agents used to increase lung development and reduce the mortality and morbidity of preterm infants with RDS. However, their safety remains uncertain, and the precise mechanisms by which they improve lung function are unclear. In previous studies, we found that vascular endothelial growth factor (VEGF) enhances the innate immune response by respiratory epithelial cells, causes a monocytic infiltration into the lung, and reduces the severity of infection by respiratory syncytial virus (RSV), a respiratory pathogen known to affect preterm infants at a high prevalence. The purpose of this study is to measure the effects of VEGF administration on local immune responses in neonatal lambs, as the ovine lung is well suited for comparison to the human lung, due to similarities in alveolar development, immune responses, and RSV susceptibility. We hypothesized that VEGF induces the expression of genes necessary for host immune responses. We analyzed global gene expression profiles in the lungs of neonate lambs treated with VEGF by real-time qPCR. We report that VEGF induced the expression of chemokines (IL-8, RANTES, MCP-1), cytokines (IFN-gamma, IL-6, TNF-alpha, GMCSF), Toll-like receptor (TLR)-4, complement family members (C3, CFB, CFH) and collectins (SP-A, SP-D). These results suggest that VEGF can regulate local immune gene expression in vivo and should be further explored as a potential exogenous therapy for various lung diseases.

Background: Preterm infants with respiratory distress syndrome (RDS) present with systemic inflammation. The role of lymphocytes in RDS is less studied. Activation of lymphocytes could mediate chronic inflammation and development of bronchopulmonary dysplasia (BPD)., Objective: To evaluate whether T cells are activated in preterm infants with RDS and whether T cell activation is associated with the development of BPD., Methods: Thirty-four infants with RDS [mean gestational age 27.1 (SD 2.0) weeks, birth weight 900 (216) g] were compared with 21 infants without RDS [32.6 (1.4) weeks, 1,697 (406) g]. From blood samples taken on postnatal days 1, 3, and 7, CD4 and CD8 cell counts and their expressions of co-stimulatory molecule CD54 and adhesion molecule CD62L were determined by flow cytometry. In activated cells, expression of CD54 is increased and CD62L is decreased., Results: As compared with infants without RDS, infants with RDS had less CD4 and CD8 cells on day 3 (both p = 0.02). On day 1 and day 3, RDS was associated with increased CD54 expression on CD4 cells (p = 0.001; p = 0.03) and decreased CD62L expression on CD8 cells (both p = 0.02). Infants with RDS who developed BPD (n = 18) had higher CD54 expression on CD4 cells on day 3 (p = 0.01) and on CD8 cells on day 1 and day 3 (p = 0.01; p = 0.04) as compared with infants without BPD (n = 16)., Conclusions: In preterm infants, RDS is associated with a lower T cell count and a higher proportion of activated cells. Increased proportion of activated T cells predicts the development of BPD. Systemic T cell activation could mediate inflammation and development of BPD., (Copyright 2009 S. Karger AG, Basel.)

Using a mouse model of neonatal respiratory distress syndrome (RDS), we demonstrate a central role for macrophage migration inhibitory factor (MIF) in lung maturation at the developmental stage when human neonates are most susceptible to RDS. We prematurely delivered mouse pups at embryonic day 18, during the early saccular stage of pulmonary development. Only 8% of the prematurely delivered pups genetically deficient in MIF survived 8 h vs 75% of wild-type controls (p<0.001). This phenotype was corrected when pups of all genotypes were bred from dams heterozygote for MIF deficiency. Local production of MIF in the lung increased at embryonic day 18, continued until full-term at embryonic day 19.5, and decreased in adulthood, thus coinciding with this developmental window. The lungs of pups genetically deficient in MIF were less mature upon histological evaluation, and demonstrated lower levels of vascular endothelial growth factor and corticosterone--two factors that promote fetal lung maturation. In vitro studies support a role for MIF in surfactant production by pulmonary epithelial cells. In a cohort of human neonates with RDS, higher intrapulmonary MIF levels were associated with a lower likelihood of developing bronchopulmonary dysplasia, a sequelae of RDS (p<0.03). This study demonstrates for the first time a role for MIF in lung maturation, and supports a protective role for MIF in newborn lung disease.

We investigated the relation between perinatal endotracheal colonization, the associated cytokine response and respiratory outcome in ventilated preterm neonates. Between September 1999 and March 2002, a cohort of 141 neonates with a gestational age <31 weeks requiring ventilation directly after birth, were followed prospectively. All were admitted to the Neonatal Intensive Care Unit, University Hospital of Antwerp, Belgium. A tracheal aspirate (TA) sample was collected soon after birth and was processed for microbiological examination, leukocyte count, and cytokine analysis (interleukins [IL] IL-1beta, IL-6, CXCL8 (formerly called IL-8), IL-10, IL-12p70 and tumor necrosis factor alpha [TNF-alpha]). Together with the prospectively registered patient's comorbidities and severity of disease, these inflammatory parameters were analyzed in a multivariate Cox proportional hazards model with time of extubation and duration of oxygen therapy as main outcome measures. Of the 141 patients included, 31 (22%) died before discharge from the unit and 37 (26%) had a positive TA culture. Independent predictors of duration of mechanical ventilation were: gestational age <28 weeks, degree of respiratory distress syndrome (RDS) at birth, significant patent ductus arteriosus (PDA), the SNAP-score, and high levels of CXCL8 (>4,153 pg/ml) in TA only in neonates with a gestational age <28 weeks. Variables associated with extended duration of oxygen therapy were gestational age <28 weeks, birth weight <1,000 g, degree of RDS at birth, and duration of mechanical ventilation., (2007 Wiley-Liss, Inc.)

In this study, we determined the genotype frequencies of polymorphisms of cytokine genes and investigated their association with the risk of respiratory distress syndrome (RDS) in preterm infants. Genetic polymorphisms in the cytokines interleukin (IL)-10, IL-8, and tumor necrosis factor (TNF) alpha, were studied in 342 white Italian newborns (112 without RDS, 66 prematurely born with RDS, and 164 infants born at term who were included as healthy controls). The polymorphisms were analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). The IL-10 mRNA levels were analyzed according to genotype by quantitative real-time PCR (QRT-PCR) in Epstein-Barr virus-transformed lymphoblastoid cell lines (EBV-LCLs) of 42 full-term healthy infants. Logistic regression analysis demonstrated the risk of RDS to be significantly lower in preterm infants with an IL-10 -1082 GG/GA genotype than in those with an AA genotype [odds ratio (OR) = 0.48, 95% confidence interval (CI): 0.24-0.95, p = 0.03]. QRT-PCR analyses showed that the IL-10 mRNA levels were significantly higher in 27 IL-10 -1082 GG/GA carriers compared with 15 IL-10 -1082 AA carriers (p = 0.03). We conclude that the IL-10 -1082 GG/GA polymorphism may have a role in RDS development in premature infants.

Aim: We investigated the role of eosinophils in the pathogenesis of bronchopulmonary dysplasia (BPD) in preterm infants., Methods: Fifteen preterm infants with BPD were compared to 13 preterms with respiratory distress syndrome (RDS) and to 16 healthy preterms. We assessed total eosinophil and neutrophil counts in venous blood samples and the levels of the eosinophilic activity markers eosinophilic cationic protein (ECP) and the cellular surface antigen (CD9)., Results: The eosinophil count was greater in BPD compared with RDS and healthy infants (1414 vs. 797 and 471 cells per microlitre, respectively, p = 0.03). ECP levels were elevated (34 vs. 12.8 and 9.8 microg/L, respectively, p = 0.002) and CD9 levels reduced (75 vs. 94 and 86 mean fluorescence intensity units, respectively, p = 0.01) in BPD compared with RDS and healthy infants, suggesting eosinophilic activation in BPD. These findings were not solely explained by differences between gestational age or birth weight of the different groups. ECP levels were positively correlated with the duration of oxygen supplementation in the BPD group. The eosinophil count fell promptly after steroid treatment was commenced in the BPD group., Conclusion: The findings suggest that BPD is linked to eosinophil activation, which might contribute to the pathogenesis.

Objective: To investigate whether or not peri/intraventricular hemorrhages (PIVHs) occurring in the first 12 hours of life (early PIVHs) are related to respiratory distress syndrome (RDS)-associated inflammatory factors in contrast to PIVHs developing after 12 hours of life (late PIVHs)., Study Design: Blood samples obtained at 0 to 12 hours, 48 to 72 hours, and 168 hours of life were evaluated for determination of the proinflammatory cytokines interleukin (IL)-8 and IL-6, tumor necrosis factor (TNF)-alpha, and malondialdehyde (MDA) as measures of lipid peroxidation. Simultaneously, cranial ultrasonography was performed in 114 neonates under 32 weeks gestational age., Results: Out of the total study group of 114 neonates, 67 (59%) had RDS. Early PIVH occurred in 16 neonates, 14 of whom (88%) had RDS. Late PIVHs occurred in 12 neonates. Neonates with RDS had higher IL-8 and IL-6 levels at 0 to 12 hours (P < .0001; < .0001) and at 48 to 72 hours (P < .001; < .01) than those without RDS. Neonates with early PIVH had higher IL-8 (P < .02), IL-6 (P < .02), and MDA (P < .01) levels at 0 to 12 hours than those with late PIVH or no PIVH. Those with early PIVH had higher IL-8 levels at 48 to 72 hours than those without PIVH (P < .02). Multiple linear regression revealed an association between RDS/early PIVH and IL-8, IL-6, and MDA levels., Conclusions: An RDS-associated increase in proinflammatory cytokine and MDA levels was associated with early PIVHs, but not with late PIVHs, suggesting a different etiopathogenesis in early versus late PIVHs.

Ventilation with an inappropriate tidal volume (Vt) triggers lung inflammation, an important predisposing factor of bronchopulmonary dysplasia. It still remains uncertain what the appropriate starting target Vt should be during the acute phase of respiratory distress syndrome (RDS). Our aim was to evaluate lung inflammation in preterm infants undergoing synchronized intermittent positive-pressure ventilation (SIPPV) with two different tidal volumes Vt during the acute phase of RDS. Thirty preterm infants (gestational age, 25-32 weeks) with acute RDS were randomly assigned to be ventilated with Vt = 5 ml/kg (n = 15) or Vt = 3 ml/kg (n = 15). Proinflammatory cytokines (interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor (TNF)-alpha) were determined in the tracheal aspirate on days 1, 3, and 7 of life. IL-8 and TNF-alpha levels collected on day 7 were significantly higher (P < 0.05), and mechanical ventilation lasted longer in the group with Vt = 3 ml/kg (16.8 +/- 4 vs. 9.2 +/- 4 days; P = 0.05). In conclusion, our data show significantly higher lung inflammation in preterm infants ventilated with Vt = 3 ml/kg, suggesting a role for Vt = 5 ml/kg in reducing both inflammatory response during the acute phase of RDS and the length of ventilation. Whether the use of this starting Vt prevents bronchopulmonary dysplasia requires further study., (2006 Wiley-Liss, Inc.)

Objective: Ventilation strategies for preterm neonates may influence the severity of pulmonary dysfunction and later development of chronic lung disease. The objective of this report is to compare the effects of high-frequency oscillatory ventilation (HFOV) versus synchronized intermittent mandatory ventilation (sIMV) from the points of views of biochemical and functional variables., Design: Randomized controlled trial., Setting: Third level NICU., Patients and Participants: Forty preterm neonates with a gestational age of 24-29 weeks were randomly assigned to one of the two above-mentioned ventilation strategies within 30 min from birth., Measurements and Results: At 1, 3, 5, and 7 days, the babies were monitored by means of ventilator indices, pulmonary function, and eight pro-inflammatory or anti-inflammatory cytokines measured in bronchoalveolar lavage fluid. The neonates assigned to the HFOV procedure benefited from early and sustained improvement in pulmonary mechanics and gas exchange-significantly higher dynamic respiratory compliance values, significantly lower expiratory airway resistance and oxygenation index values-with earlier extubation as compared to the neonates assigned to sIMV treatment, and showed significantly lower transforming growth factor-beta1 concentrations in bronchoalveolar lavage fluid., Conclusions: The results of this randomized clinical trial support the hypothesis that early and exclusive use of HFOV, combined with optimum volume strategy, has a beneficial effect during the acute phase of lung injury.

A grave form of HDN (haemolytic disease of the new-born) is described in female twins, caused by Kell, E and Vel isoimmunisation. The weakly vital and anaemic new-born babies were hospitalised with signs of respiratory distress on the first day of their life after the delivery by Caesarean section in the 38 (th) week of pregnancy in the General Hospital Dubrovnik. Already during the first hours of their life jaundice developed with a high bilirubin level for their age. The direct Coombs' test on the twins and the indirect Coombs' test on the mother were positive. Immuno-haematological analysis proved the presence of anti-Kell, anti-E and the very rare anti-Vel antibodies in the mother's serum and in the plasma of both twins. We had no possibility to obtain appropriate blood for the indicated exsanguine transfusion because cross-probes with the accessible blood samples were positive. Up to the fourteenth day of life the anaemia deepened and was aggravated in one twin, the Kell positive one (phenotype CcDEe,Kk) in relation to the other, the Kell negative (phenotype CcDEe,kk) twin. The recovery of the female twins started on the 15 (th) day of life, after the transfusion of blood (phenotype: 0,ccddee, Vel negative, Kel negative), received from the bank of rare blood groups in London. This is the first described case of haemolytic disease of the new-born caused by antibodies on the antigen Kell, E and Vel. The low frequency of immunisation with rare antigens such as Kell, E and Vel, does not exclude the possibility of the occurrence of grave forms of haemolytic disease. All pregnant women with a positive indirect Coombs' test should be further immuno-haematologically tested in order to identify the antibodies type so that the treatment of the new-borns could be commenced in time.

Reactive oxygen species play an important role in the pathogenesis of respiratory distress syndrome and its complications. This study was conducted to determine if treatment with the antioxidant melatonin would influence interleukin-6, interleukin-8, tumor necrosis factor alpha, and nitrite/nitrate levels in newborns with grade III or IV respiratory distress syndrome (radiographically confirmed) diagnosed within the first 6 hours of life. Prior to treatment, a blood sample was collected from the umbilical cord or a peripheral vein of each newborn. Second, third, and fourth blood samples were collected at 24 hours, 72 hours, and 7 days, respectively, after beginning treatment with melatonin or placebo. Compared with the melatonin-treated respiratory distress syndrome newborns, in the untreated infants the concentrations of interleukin-6, interleukin-8, and tumor necrosis factor alpha were significantly higher at 24 hours, 72 hours, and at 7 days after onset of the study. in addition, nitrite/nitrate levels at all time points were higher in the untreated respiratory distress syndrome newborns than in the melatonin-treated babies. Following melatonin administration, nitrite/nitrate levels decreased significantly, whereas they remained high and increased further in the respiratory distress syndrome infants not given melatonin.

Indicators of coagulation activation are sometimes increased in the blood of newborns and adults who have a systemic inflammatory response. These coagulation factors have the ability to exacerbate inflammation, which in turn can promote coagulation. Therapies directed solely at coagulation factors and therapies directed solely at inflammation factors have not proved effective in reducing mortality in adults with a systemic inflammatory response syndrome and multi-organ dysfunction (SIRS/MOD). On the other hand, the only therapy that has reduced mortality in SIRS/MOD is activated protein C, which has both anti-coagulation and anti-inflammatory effects. This and other observations support the view that activated coagulation factors enhance inflammation. Since newborns at risk of cerebral white matter damage and cerebral palsy are more likely than their peers to have a systemic inflammatory response, which is sometimes accompanied by elevated blood levels of coagulation factors, we suggest that activated coagulation factors contribute to the occurrence of cerebral white matter damage by exacerbating inflammatory phenomena, rather than by occluding cerebral blood vessels.

Spontaneous preterm birth due to intrauterine infection is associated with increased concentrations of cytokines in amniotic fluid and in the airways at birth. Intra-amniotic IL-1 induces fetal lung maturity, consistent with the decrease in the incidence of respiratory distress syndrome (RDS) in intrauterine inflammation. On the other hand, antenatal corticosteroid decreases the incidence of RDS in infants born prematurely. The aim of the present study was to investigate the interaction between IL-1 and glucocorticoid in the expression of the surfactant proteins SP-A, -B, and -C. Lung explants from rabbit fetuses at 22 (immature), 27 (transitional), and 30 (mature) d of gestation (term, 30-31 d) and on d 1 after term birth were cultured with dexamethasone (Dx), IL-1alpha, or vehicle in the presence or absence of actinomycin D. According to the present results, IL-1alpha and Dx additively increased the expression of SP-A and SP-B on d 22. Later in gestation, SP-B and SP-C were suppressed by IL-1, whereas glucocorticoid tended to increase the expression of SP-B and SP-C and prevented the IL-1-induced suppression of SP. IL-1alpha and steroid interactively increased the stability of SP mRNA compared with the single agonist, possibly explaining the additive effects on the SP mRNA levels. The present results reveal beneficial additive effects of glucocorticoid and cytokine on lung surfactant. They may explain some of the acute beneficial effects of glucocorticoid therapy in chorioamnionitis before premature birth and in inflammatory lung disease after birth.

A key role for inflammation in the etiology of bronchopulmonary dysplasia (BPD) has been proposed. In the present study we have evaluated lymphocyte subpopulations in 39 premature infants with respiratory distress syndrome (RDS) who did or did not develop BPD. The absolute number of lymphocytes was lower among infants with RDS who developed BPD compared with those who did not over the first two weeks of life ( p < 0.020) as were percentage and absolute number of CD4(+) T cells. By contrast, the proportions of CD3(+)CD8(+) lymphocyte cells were not statistically different between non-BPD and BPD infants. B cell percentage was significantly decreased in BPD infants only on day 7. NK "bright" cells (CD56(+)) were highly enriched in all RDS groups. Interestingly, the percentage of CD4(+) T cells expressing CD62L was selectively reduced in BPD infants. As a whole these data suggest that reduction of CD4(+) T cells and especially those important in tissue migration and immune surveillance may be a factor in the pathogenesis of BPD.

Objective: To determine whether the presence of the proinflammatory cytokine interleukin (IL)-1beta in the lungs of preterm infants immediately after birth was associated with maternal inflammation and could predict adverse neonatal outcome., Study Design: Prospective evaluation of serially obtained tracheal aspirates for the presence of IL-1beta in 25 preterm infants (birth weight 595-1700 g; gestational age 24-32 weeks) with respiratory distress syndrome. The initial tracheal aspirate was obtained within 1 h after delivery., Results: An initial tracheal aspirate positive for IL-1beta had a highly significant correlation with documented maternal chorioamnionitis for the given patient. In addition, the presence of IL-1beta correlated significantly with elevated total cell count (2.62 vs. 0.96 x 10(6)/ml, p = 0.0097), granulocyte count (2.12 vs. 0.22 x 10(6)/ml, p = 0.001), macrophage count (0.28 vs. 0.01 x 10(6)/ml, p = 0.02) and the presence of proinflammatory cytokines IL-6, IL-8 and tumor necrosis factor (TNF)-alpha. Preterm neonates positive for IL-1beta in their initial sample were on prolonged assisted ventilation (38 vs. 16 days, p = 0.013) and oxygen supplementation (62 vs. 40.5 days, p = 0.0462) and required prolonged hospitalization (69 vs. 46 days, p = 0.0165)., Conclusions: The concentration of IL-1beta in the initial tracheal aspirate obtained from the lungs of preterm infants within the first hour of life may serve as a marker of antenatal/perinatal inflammation, probably due to maternal chorioamnionitis, and could predict an adverse clinical course and short-term outcome.

Pro-inflammatory cytokines such as IL-8 play an important role in the inflammatory response to neonatal airway injury. Difficulty in detecting counter-regulatory cytokines such as IL-10 in lavage fluid from preterm infants led to the suggestion that its deficit may be a factor in the etiology of chronic lung disease of prematurity (CLD). The aim of the study was to determine IL-8 and IL-10 concentrations in lavage fluid from preterm infants ventilated for respiratory distress syndrome. Fifty infants <30 wk gestation were studied who had been randomized to receive a natural or synthetic surfactant. Lavage samples were collected daily for the first week and twice weekly thereafter. Samples were immediately centrifuged and stored at -70 degrees C. Cytokine concentrations were quantified in duplicate using commercially available sandwich ELISA kits. Lavage IL-10 concentration, at a minimum initially, rose significant over the first five postnatal days (p = 0.009). In the same samples, lavage IL-8 concentrations rose significantly over the first postnatal week (p < 0.001), the rise preceding that of IL-10. Infants dying or developing CLD had a significant early rise in both cytokine concentrations. Compared with infants developing CLD, lavage IL-10 concentrations were significantly higher on d 1 among those not developing CLD but significantly lower on d 4 (p < 0.05). To conclude, IL-10 is detectable in lavage fluid from ventilated preterm infants and its concentrations rise significantly over the first five postnatal days. In the same samples, IL-8 concentration also rises and this increase precedes the rise in IL-10.

Objective: To study neutrophil activation in circulation as a sign of systemic inflammation in preterm infants with respiratory distress syndrome., Methods: The study comprised very low birth weight preterm infants who had respiratory distress syndrome and required intubation and mechanical ventilation (n = 51), 1-day-old preterm infants who had no need for mechanical ventilation (n = 12), term infants (n = 47), and adult volunteers (n = 25). Neutrophil surface expression of CD11b was quantified with flow cytometry., Results: In preterm infants with respiratory distress syndrome, neutrophil CD11b expression during the first day of life was higher than in cord blood (mean: 165 relative fluorescence units [RFU] [standard deviation [SD]: 53], n = 29 vs 83 RFU [SD: 21], n = 11; 95% confidence interval [CI] for difference: 59-106) or in preterm infants without mechanical ventilation (106 RFU [SD: 33], n = 12; 95% CI for difference: 17-90). CD11b expression decreased by age of 10 days. CD11b expression was lower in preterm cord than in term cord blood (95% CI for difference: 5-53). However, in preterm infants with respiratory distress syndrome aged 2 to 5 days, it was higher than in term infants of that age., Conclusions: The observations demonstrate an early transient postnatal neutrophil activation indicative of systemic inflammation that may contribute to the tissue injury in preterm infants with respiratory distress syndrome.

Intra-amniotic lipopolysaccharide (LPS) and cytokines may decrease respiratory distress syndrome (RDS) and increase chronic lung disease in the newborn. The aim was to identify the primary inflammatory mediators regulating the expression of surfactant proteins (SP) in explants from immature (22-day-old fetus) and mature (30-day term fetus and 2-day-old newborn) rabbits. In immature lung, interleukin (IL)-1alpha and IL-1beta upregulated the expression of SP-A and SP-B. These effects of IL-1 were diminished, and SP-C mRNA was suppressed additively in the presence of tumor necrosis factor (TNF)-alpha and either LPS or interferon (IFN)-gamma. LPS, TNF-alpha, or IFN-gamma had no effect alone. In explants from the term fetus and the newborn, LPS, IL-1alpha, and TNF-alpha additively suppressed the SPs. LPS acutely induced IL-1alpha in alveolar macrophages in mature lung but not in the immature lung. IFN-gamma that generally has low expression in intrauterine infection decreased the age dependence of the other agonists' effects on SPs. The present study serves to explain the variation of the pulmonary outcome after an inflammatory insult. We propose that IL-1 from extrapulmonary sources induces the SPs in premature lung and is responsible for the decreased risk of RDS in intra-amniotic infection.

Intraamniotic endotoxin causes chorioamnionitis, which is followed by improved fetal lung function after 4 d in fetal sheep. We evaluated 0.1 mg, 1 mg, 4 mg, and 10 mg endotoxin for inflammation and lung maturation effects after 7 d. Four and 10 mg endotoxin caused similar lung maturation and inflammation in the lung and chorioamnion. The number of neutrophils in cord blood and the inflammatory cells in alveolar lavage and fetal lung tissue increased in a dose-dependent manner. Lower endotoxin doses induced indicators of chorioamnionitis, lung and systemic inflammation without inducing lung maturation. Therefore, some degree of inflammation can occur without subsequent lung maturation. The inflammatory changes caused by 4 mg endotoxin were assessed after 5 h, 24 h, 72 h, and 7 d to discern local versus systemic inflammation after intraamniotic endotoxin. At 5 h active inflammatory cells were in the airways producing hydrogen peroxide, and interleukin-6 and -8 were increased in the cord blood indicating both lung and systemic responses. Cells recruited into the amniotic fluid produced proinflammatory cytokine mRNA for 7 d with no cytokine mRNA in chorioamnion, lung, or spleen after 72 h. The cells in the amniotic fluid may be a source of prolonged fetal exposure to proinflammatory cytokines.

Unlabelled: The aim of this study was to investigate the effect of prematurity, neonatal sepsis, respiratory distress syndrome (RDS) and perinatal asphyxia on monocyte HLA-DR expression of neonates using a flow cytometric method based on monocyte negative selection. The subjects were one hundred and thirty-one neonates (59 healthy, 44 septicaemic, 20 with RDS and eight with perinatal asphyxia) and 20 healthy adults. Monocyte HLA-DR expression was measured using one-colour HLA-DR labelling in a gate for monocytes obtained using the combination of CD3-CD19--PE/CD15--FITC MoAbs. In addition, the common dual staining method using MoAbs against two CD14 epitopes (TUK4, MO2) was evaluated. With the one-colour HLA-DR labelling higher purity and recovery values of monocytes were achieved than with the dual labelling, Method: Healthy neonates had significantly lower percentages of HLA-DR(+) monocytes than adults (69 +/- 13% versus 91.5 +/- 2.5%) and comparable mean fluorescence intensity (MFI) (119 +/- 25 versus 131 +/- 26). Values did not differ significantly between healthy term and preterm neonates. Preterm neonates with RDS had a significantly lower percentage of HLA-DR(+) monocytes than the healthy preterm neonates. In neonates with asphyxia both parameters were comparable to those of the healthy ones. Septicaemic neonates presented significantly lower values of both parameters than the healthy, RDS and asphyxiated neonates. Monocyte negative selection provides a reliable estimation of HLA-DR expression on monocytes. Expression of monocyte HLA-DR is lower in healthy neonates in comparison with adults and is further decreased in neonates with sepsis and RDS, but it is not influenced by prematurity and perinatal asphyxia.