Cystic fibrosis (CF) is characterized by inflammatory lung disease that significantly contributes to morbidity and mortality. Airway epithelial cells play a role in the inflammatory signaling in CF and have been reported to exhibit a number of dysfunctions in signaling cascades that modulate inflammation. Previously, we reported that the activity of nuclear factor erythroid-derived-like 2 (Nrf2), a transcription factor that regulates antioxidant and cytoprotective protein expression, is diminished in CF epithelia ( 7 ). In this report, we examined the mechanism of Nrf2 dysregulation in vitro in human airway epithelial cell lines and primary cells and in vivo in nasal epithelia excised from ΔF508 CF mutant mice. We found that cAMP-mediated signaling markedly reduces Nrf2 activity in CF vs. non-CF cells. Rp-cAMPS, a cAMP competitor, significantly corrected Nrf2 activity in CF cells, predominantly by increasing the nuclear accumulation of the transcription factor. Furthermore, we found that Rp-cAMPS significantly decreased NF-κB activation following inflammatory stimulation of CF cells. Further investigation revealed that Nrf2 and NF-κB compete for the transcriptional coactivator cAMP responsive element-binding protein (CREB) binding protein (CBP) and that Rp-cAMPS shifts CBP association in favor of Nrf2. Thus our findings provide a link between feedback to CF transmembrane regulator dysfunction and dysregulation of an inflammatory signaling pathway that modulates the coordinated activities of Nrf2 and NF-κB. Furthermore, our studies suggest that strategies that shift CBP association away from NF-κB and toward Nrf2 could have potential therapeutic efficacy for reducing inflammation in patients with CF.

WHAT'S KNOWN ON THIS SUBJECT: Childhood interstitial lung diseases occur in a variety of clinical contexts and are associated with high morbidity and mortality. Advances in the understanding of disease pathogenesis and use of standardized terminology have facilitated increased case ascertainment. WHAT THIS STUDY ADDS:This study demonstrates that cases of newly described forms of childhood interstitial lung diseases likely occur at all children' s hospitals. With advances in genetic testing and recognition of imaging patterns, a significant portion of cases are identifiable with noninvasive evaluations. abstract OBJECTIVE: Childhood interstitial lung diseases (ILD) occur in a variety of clinical contexts. Advances in the understanding of disease pathogenesis and use of standardized terminology have facilitated increased case ascertainment. However, as all studies have been performed at specialized referral centers, the applicability of these findings to general pulmonary practice has been uncertain. The objective of this study was to determine the historical occurrence of childhood ILD to provide information reflecting general pediatric pulmonary practice patterns. METHODS:Childhood ILD cases seen at Vanderbilt Children' s Hospital from 1994 to 2011 were retrospectively reviewed and classified according to the current pediatric diffuse lung disease histopathologic classification system. RESULTS:A total of 93 cases were identified, of which 91.4% were classifiable. A total of 68.8% (64/93) of subjects underwent lung biopsy in their evaluations. The largest classification categories were disorders related to systemic disease processes (24.7%), disorders of the immunocompromised host (24.7%), and disorders more prevalent in infancy (22.6%). Eight cases of neuroendocrine cell hyperplasia of infancy (NEHI) were identified, including 5 that were previously unrecognized before this review.CONCLUSIONS: Our findings demonstrate the general scope of childhood ILD and that these cases present within a variety of pediatric subspecialties. Retrospective review was valuable in recognizing more recently described forms of childhood ILD. As a significant portion of cases were classifiable based on clinical, genetic, and/or radiographic criteria, we urge greater consideration to noninvasive diagnostic approaches and suggest modification to the current childhood ILD classification scheme to accommodate the increasing number of cases diagnosed without lung biopsy. Pediatrics 2013;132:684-691

Maternal folate status and body mass index (BMI) are independent risk factors for neural tube defects (NTD). Population-based studies have identified an inverse association between serum folate and BMI, after adjusting for intake. The objective of this intervention study was to compare the relationship between BMI and the short-term pharmacokinetic response to an oral dose of folic acid. Healthy obese (BMI 30.0 kg m(-2); n=16) and normal-weight (BMI 18.5-24.9 kg m(-2); n=16) women of childbearing age (18-35 years) were administered a single oral dose of folic acid (400 μg). Blood samples were collected over a 10-h period to evaluate the serum folate response. Fasting baseline serum folate was lower in the obese group (P=0.005); in contrast, red blood cell folate was higher (P=0.05). Area-under-the-curve for the absorption phase (0-3 h) and peak serum folate concentrations were lower in obese versus normal-weight women (P<0.005). Overall serum folate response (0-10 h) was lower in obese versus normal-weight women (repeated-measures ANOVA, P=0.001). Data suggest body distribution of folate is significantly affected by obesity, and, should pregnancy occur, may reduce the amount of folate available to the developing embryo. These findings provide additional support for a BMI-adjusted folic acid intake recommendation for NTD risk reduction.

Background Staphylococcus aureus is one of the earliest bacterial pathogens to colonize the lungs of children with cystic fibrosis and is an important contributor to pulmonary exacerbations. The adaptive host response to S. aureus in cystic fibrosis remains inadequately defined and has important implications for pathogenesis and potential interventions. The objectives of this study were to determine the functional antibody response to select staphylococcal exotoxins (LukAB, alpha-hemolysin, and PVL) in children with cystic fibrosis and to evaluate the relationship of this response with pulmonary exacerbations. Methods Fifty children with cystic fibrosis were enrolled and followed prospectively for 12 months. Clinical characteristics and serologic profiles were assessed at routine visits and during pulmonary exacerbations, and functional antibody assessments were performed to measure neutralization of LukAB-mediated cytotoxicity. Results For each antigen, geometric mean titers were significantly higher if S. aureus was detected at the time of exacerbation. For LukAB, GMTs were significantly higher at exacerbation follow-up compared to titers during the exacerbation, consistent with expression during human disease, and the humoral response capably neutralized LukAB-mediated cytotoxicity. Moreover, the presence of a positive S. aureus culture during a pulmonary exacerbation was associated with a 31-fold higher odds of having a LukA titer ≥1:160, suggesting potential diagnostic capability of this assay. Conclusions The leukotoxin LukAB is expressed by S. aureus and recognized by the human adaptive immune response in the setting of pulmonary infection in cystic fibrosis. Anti-LukAB antibodies were not only predictive of positive staphylococcal culture during exacerbation, but also functional in the neutralization of this toxin.