Project description:Genome wide DNA methylation profiling study of PBMC from 71 unique primary patient blood samples. The Illumina Human Methylation 450k array was used. 29 challenge proven food allergy, 29 sensitized but oral tolerant, 13 non food allergics Mixture of food allergy phenotypes (egg allergic (15), peanut allergic (14)), food sensitization phenotypes (egg sensitized (14), peanut sensitized (15)). 4 samples had technical replicate hybridzations. Bisulphite converted DNA from the 75 samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip v1.2. Technical replicates were combined during processing, resulting in normalized Beta values for 71 unique primary patient blood samples.
Project description:Bronchopulmonary dysplasia (BPD) is the most common respiratory disease in preterm infants born at less than 28 weeks gestation. Most existing clinical prediction models for BPD show limited accuracy in predicting BPD development when validated using external data, stressing the need for novel biomarkers to identify at-risk infants for early and effective interventions. We leveraged existing frozen umbilical cord blood samples from the Northwestern University Cord Blood Biobank (NUCord) to perform parallel transcriptional and DNA methylation profiling. Chorioamnionitis-associated differentially expressed genes (DEGs) in our cohort included markers previously established in clinical and animal BPD studies, such as genes related to NF-κB signaling and immune responses. Importantly, these genes were highly associated with chorioamnionitis infection status specifically in preterm infants. We also identified that BPD development is associated with disrupted methylation signatures in microRNA genes and genes associated with glucose metabolism. Our results suggest that BPD development and chorioamnionitis are associated with distinct transcriptomic and epigenetic signatures when compared with healthy term and preterm infants. These signatures may represent biomarkers measurable at birth that predict BPD development during a time window when preventative or therapeutic interventions could be applied.
Project description:Bronchopulmonary dysplasia (BPD) is the most common respiratory disease in preterm infants born at less than 28 weeks gestation. Most existing clinical prediction models for BPD show limited accuracy in predicting BPD development when validated using external data, stressing the need for novel biomarkers to identify at-risk infants for early and effective interventions. We leveraged the existing buffy coat of the frozen umbilical cord blood samples from the Northwestern University Cord Blood Biobank (NUCord) to perform parallel RNA and DNA extraction. BPD-associated differentially expressed genes (DEGs) includes BPD marker established in previous mouse studies and gene related to NF-κB signaling and immune responses. We also identified that BPD development is associated with disrupted methylation signatures in microRNA genes and genes associated with disrupted glucose metabolism. Our results suggest that BPD development is associated with distinct epigenetic and transcriptomic signatures when compared to healthy term infants and preterm infants. These signatures may represent biomarkers measurable at birth that predict BPD development during a time window when preventative or therapeutic interventions could be applied.
Project description:Background: Cow's milk allergy (CMA) is one of the most common food allergies (FA) in childhood. This condition can be IgE-mediated, non-IgE-mediated, or a combination of both. Diagnosis involves clinical history in conjunction with sensitization tests. However, these tests have limited predictive value, making the oral food challenge (OFC) the gold standard for diagnosis. Recent research has focused on identifying biomarkers, including DNA methylation patterns, for FA diagnosis. The aim of this study is to investigate the differences in DNA methylation associated with distinct patterns of CMA, to identify novel diagnostic biomarkers. Methods: Genome-wide DNA methylation profiling was performed on blood samples from infants with IgE-mediated CMA (CMAIE), non-IgE-mediated CMA (CMANIE), and non-allergic controls, at baseline and after 6 months of a exclusion diet in CMA groups. These results were then correlated with tolerance acquisition following the restrictive diet. Results: A total of 19 infants were enrolled (10 CMAIE, 6 CMANIE, and 3 controls). Significant differentially methylated regions (DMRs) annotated to both genes and promoters were identified in all groups, and a clear separation of the samples into their respective groups was observed. Furthermore, DMRs in promoters and genes were identified in tolerant CMAIE children after the exclusion diet, being associated to tolerance. Discussion: Differential DNA methylation in CMA children is a useful diagnostic biomarker, and it could also be valuable in predicting the resolution of such pathologies.
Project description:Bronchopulmonary dysplasia (BPD) is a lung disease in premature infants characterized by impaired pulmonary development which persists into later life. While advances in neonatal care have improved survival rates of premature infants, cases of BPD haves been increased. Therapeutic options are limited for prevention and treatment. This study was designed to explore the relationship between gestational age (GA), birth weight and estímate blood cell-type composition in premature infants and to elucidate early epigenetic biomarkers associated with BPD. Peripheral blood DNA (at days 14 and 28) from preterm neonates that went on to develop BPD (n = 14) or not (nonBPD, n = 93) was applied to Illumina EPIC methylation arrays. Using DNA methylation analysis of cord blood DNA, we investigated association of GA and birth weight with the estimated distribution of cord blood cell types, particularly the nucleated red blood cell (NRBC) in a pilot-size cohort of preterm infants with or without BPD. We describe changes in methylation-based estimates of blood cell-type composition in relation to GA and birth weight. After adjusting for covariates (GA, birth weight, cell type proportions, etc.) we identify differentially methylated CpGs and genes associated with BPD at different time points.
Project description:Bronchopulmonary dysplasia (BPD) is a lung disease in premature infants characterized by impaired pulmonary development which persists into later life. While advances in neonatal care have improved survival rates of premature infants, cases of BPD haves been increased. Therapeutic options are limited for prevention and treatment. This study was designed to explore the relationship between gestational age (GA), birth weight and estímate blood cell-type composition in premature infants and to elucidate early epigenetic biomarkers associated with BPD. Cord blood DNA from preterm neonates that went on to develop BPD (n = 14) or not (nonBPD, n = 93) was applied to Illumina 450K methylation arrays. Using DNA methylation analysis of cord blood DNA, we investigated association of GA and birth weight with the estimated distribution of cord blood cell types, particularly the nucleated red blood cell (NRBC) in a pilot-size cohort of preterm infants with or without BPD. We describe changes in methylation-based estimates of blood cell-type composition in relation to GA and birth weight. After adjusting for covariates (GA, birth weight, cell type proportions, etc.) we identify differentially methylated CpGs and genes associated with BPD.
Project description:Necrotizing enterocolitis (NEC), a severe gut disorder in preterm infants, is difficult to predict due to poor specificity and sensitivity of clinical signs and biomarkers. Using preterm piglets as a model, we hypothesized that early development of NEC affects blood gene expression, potentially related to early systemic immune responses. In this animal model, variable severity of gut NEC lesions were detected in 5d-old piglets with limited clinical signs. NEC (n=20) and control piglets (CON, n=19) were analyzed for whole blood transcriptome, revealing 344 differentially expressed genes (DEGs) between NEC and CON piglets. Co-expression network analyses and qPCR suggested AOAH, FKBP5, PAK2 as three NEC-specific genes associated with severe gut lesions. These results suggest that whole blood gene expressions are affected in preterm piglets when clinical symptoms of NEC are minimal. Blood transcriptome may be a novel tool to identify early biomarkers of NEC.
Project description:Staphylococcus (S.) epidermidis is one of the most common nosocomial coagulase-negative staphylococci infections in preterm infants. The clinical signs of infection are often unspecific and identification of novel markers to complement the current diagnosis is needed. In this study, we investigated proteomic alterations in the neonatal mouse brain following S. epidermidis infection and in the blood in preterm infants. We identified lipocalin 2 (LCN2) as a crucial protein associated with cerebrovascular changes and astrocyte reactivity in mice. While astrocytes were activated in S. epidermidis infected mice, LCN2 protein expression in the brain was associated with endothelial cells but not astrocyte reactivity. By combining weighted gene co-expression analysis and differential expression approaches, we further identified that LCN2 protein was linked to blood C-reactive protein levels in a cohort of preterm infants born <28 weeks of gestation. Blood LCN2 levels were associated with similar alterations of cytokines and chemokines in both infected mice and human preterm infants with increased levels of CRP. The present experimental and clinical study indicates that LCN2 might be a suitable additional marker of preterm infection/inflammation associated with cerebrovascular changes and neuroinflammation.