Perceived Versus Actual Aeroallergen Sensitization in Urban Children.

BACKGROUND: Individuals often report allergy to specific aeroallergens, but allergy testing can reveal disparate sensitization. OBJECTIVE: To characterize the agreement between perceived and actual sensitization to individual aeroallergens in an urban pediatric population. METHODS: A total of 253 children were enrolled from pediatric clinics in New York, NY. Detailed questionnaires regarding perceived sensitization and serum specific IgE measurements to 10 common aeroallergens were completed. Agreement between perceived and actual sensitization (sIgE ≥ 0.35 kUA/L) to individual aeroallergens was assessed by Cohen's kappa. Multivariable logistic regression models adjusted for potential confounders were used to test for associations between perceived and actual sensitization. RESULTS: A total of 161 (63.6%) of 253 children reported perceived sensitization to 1 or more aeroallergen, and 203 (80.2%) were actually sensitized to 1 or more aeroallergen. Agreement between perceived and actual aeroallergen sensitization was fair for most aeroallergens, with greatest agreement for cat dander (κ, 0.42; 95% CI, 0.32-0.53) and dust (κ, 0.32; 95% CI, 0.20-0.44). Models adjusted for potential confounders showed nearly 6-fold odds of sensitization to cat dander given perceived cat allergy (adjusted odds ratio, 5.82; 95% CI, 2.91-11.64), and over 2-fold odds of sensitization to Dermatophagoides pteronyssinus, Dermatophagoides farinae, dog dander, or grass pollen given perceived sensitization to their respective allergens. Among children with no perceived sensitization, actual sensitization ranged from 5.4% to 30.4%, and was more common for indoor versus outdoor allergens, including cockroach. CONCLUSIONS: Children who perceive allergen sensitization to cat, dog, dust, or grass are likely to demonstrate actual sensitization to these individual allergens. Children with no perceived sensitization to allergens are nonetheless frequently sensitized.

The nasal microbiome in asthma.

BACKGROUND: Nasal microbiota may influence asthma pathobiology. OBJECTIVE: We sought to characterize the nasal microbiome of subjects with exacerbated asthma, nonexacerbated asthma, and healthy controls to identify nasal microbiota associated with asthma activity. METHODS: We performed 16S ribosomal RNA sequencing on nasal swabs obtained from 72 primarily adult subjects with exacerbated asthma (n = 20), nonexacerbated asthma (n = 31), and healthy controls (n = 21). Analyses were performed using Quantitative Insights into Microbial (QIIME); linear discriminant analysis effect size (LEfSe); Phylogenetic Investigation of Communities by Reconstruction of Unobserved States; and Statistical Analysis of Metagenomic Profiles (PICRUSt); and Statistical Analysis of Metagenomic Profiles (STAMP). Species found to be associated with asthma activity were validated using quantitative PCR. Metabolic pathways associated with differentially abundant nasal taxa were inferred through metagenomic functional prediction. RESULTS: Nasal bacterial composition significantly differed among subjects with exacerbated asthma, nonexacerbated asthma, and healthy controls (permutational multivariate ANOVA, P = 2.2 × 10-2). Relative to controls, the nasal microbiota of subjects with asthma were enriched with taxa from Bacteroidetes (Wilcoxon-Mann-Whitney, r = 0.33, P = 5.1 × 10-3) and Proteobacteria (r = 0.29, P = 1.4 × 10-2). Four species were differentially abundant based on asthma status after correction for multiple comparisons: Prevotella buccalis, Padj = 1.0 × 10-2; Dialister invisus, Padj = 9.1 × 10-3; Gardnerella vaginalis, Padj = 2.8 × 10-3; Alkanindiges hongkongensis, Padj = 2.6 × 10-3. These phyla and species were also differentially abundant based on asthma activity (exacerbated asthma vs nonexacerbated asthma vs controls). Quantitative PCR confirmed species overrepresentation in asthma relative to controls for Prevotella buccalis (fold change = 130, P = 2.1 × 10-4) and Gardnerella vaginalis (fold change = 160, P = 6.8 × 10-4). Metagenomic inference revealed differential glycerolipid metabolism (Kruskal-Wallis, P = 1.9 × 10-4) based on asthma activity. CONCLUSIONS: Nasal microbiome composition differs in subjects with exacerbated asthma, nonexacerbated asthma, and healthy controls. The identified nasal taxa could be further investigated for potential mechanistic roles in asthma and as possible biomarkers of asthma activity.

Non-Specific Blocking of miR-17-5p Guide Strand in Triple Negative Breast Cancer Cells by Amplifying Passenger Strand Activity.

Conventional wisdom holds that only one of the two strands in a micro ribonucleic acid (miRNA) precursor duplex is selected as the active miRNA guide strand. The complementary miRNA passenger strand, however, is thought to be inactive. High levels of the oncogenic miRNA (oncomiR) guide strand called miR-17-5p is overexpressed in triple negative breast cancer (TNBC) and can inhibit ribosomal translation of tumor suppressor gene mRNAs, such as programmed cell death 4 (PDCD4) or phosphatase and tensin homolog (PTEN). We hypothesized that knocking down the oncogenic microRNA (oncomiR) miR-17-5p might restore the expression levels of PDCD4 and PTEN tumor suppressor proteins, illustrating a route to oligonucleotide therapy of TNBC. Contrary to conventional wisdom, antisense knockdown of oncomiR miR-17-5p guide strand reduced PDCD4 and PTEN proteins by 1.8±0.3 fold in human TNBC cells instead of raising them. Bioinformatics analysis and folding energy calculations revealed that mRNA targets of miR-17-5p guide strand, such as PDCD4 and PTEN, could also be regulated by miR-17-3p passenger strand. Due to high sequence homology between the antisense molecules and miR-17-3p passenger strand, as well as the excess binding sites for the passenger strand on the 3'UTR of PDCD4 and PTEN mRNAs, introducing a miR-17-3p DNA-LNA mimic to knock down miR-17-5p reduced PDCD4 and PTEN protein expression instead of raising them. Our results imply that therapeutic antisense sequences against miRNAs should be designed to target the miRNA strand with the greatest number of putative binding sites in the target mRNAs, while minimizing affinity for the minor strand.