👤 Olesya Rusyn

Allergen-specific immunotherapy (AIT) is the only disease-modifying treatment in allergic airway diseases. Underlying immunological mechanisms and candidate biomarkers, which may be translated into predictive/surrogate measures of clinical efficacy, remain an active area of research. The aim of this study was to evaluate Pollinex Quattro (PQ) Grass AIT induced immunomodulatory mechanisms, based on transcriptome profiling of peripheral blood mononuclear cells. 119 subjects with grass pollen induced seasonal allergic rhinitis (SAR) were randomized in a 2:2:1:1 ratio to receive a cumulative dose of PQ Grass as a conventional or extended pre-seasonal regimen, placebo, or placebo with MicroCrystalline Tyrosine. Gene expression analysis was an exploratory endpoint evaluated in a subgroup of 30 subjects randomly selected from the four treatment arms. Samples were collected at three time points: screening (baseline), before the start of the grass pollen season and at the end of the season. This study was funded by the manufacturer of PQ. Transcriptome analysis demonstrated that the most significant changes in gene expression, for both treatment regimens, were at the end of the grass pollen season, with the main Th1 candidate molecules (IL-12A, IFNγ) upregulated and Th2 signature cytokines downregulated (IL-4, IL-13, IL-9) (p < .05). Canonical pathways analysis demonstrated Th1, Th2, Th17 and IL-17 as the most significantly enriched pathways based on absolute value of activation z-score (IzI score ≥ 2, p < .05). Upstream regulator analysis showed pronounced inhibition of pro-inflammatory allergic molecules IgE, IL-17A, IL-17F, IL-25 (IL-17E) (IzI score ≥ 2, FDR < 0.05) and activation of pro-tolerogenic molecules IL-12A, IL-27, IL-35 (EBI3) at the end of the grass pollen season. Peripheral blood mononuclear cells transcriptome profile showed an inhibition of Th2, Th17 pro-inflammatory allergic responses and immune deviation towards Th1 responses. PQ Grass extended regimen exhibited a superior mechanistic efficacy profile in comparison with PQ conventional regimen. Show less

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent chronic liver disease, and patient susceptibility to its onset and progression is influenced by several factors. In this study, we investigated whether altered hepatic DNA methylation in liver tissue correlates with the degree of severity of NAFLD-like liver injury induced by a high-fat and high-sucrose (HF/HS) diet in Collaborative Cross (CC) mice. Using genome-wide targeted bisulphite DNA methylation next-generation sequencing, we found that mice with different non-alcoholic fatty liver (NAFL) phenotypes could be distinguished by changes in hepatic DNA methylation profiles. Specifically, NAFL-prone male CC042 mice exhibited more prominent DNA methylation changes compared with male CC011 mice and female CC011 and CC042 mice that developed only a mild NAFL phenotype. Moreover, these mouse strains demonstrated different patterns of DNA methylation. While the HF/HS diet induced both DNA hypomethylation and DNA hypermethylation changes in all the mouse strains, the NAFL-prone male CC042 mice demonstrated a global predominance of DNA hypermethylation, whereas a more pronounced DNA hypomethylation pattern developed in the mild-NAFL phenotypic mice. In a targeted analysis of selected genes that contain differentially methylated regions (DMRs), we identified NAFL phenotype-associated differences in DNA methylation and gene expression of the Show less

Non-alcoholic fatty liver disease (NAFLD), one of the most common forms of chronic liver disease, is characterized by the excessive accumulation of lipid species in hepatocytes. Recent studies have indicated that in addition to the total lipid quantities, changes in lipid composition are a determining factor in hepatic lipotoxicity. Using ultra-high performance liquid chromatography coupled with electrospray tandem mass spectrometry, we analyzed the esterified fatty acid composition in 24 strains of male and female Collaborative Cross (CC) mice fed a high fat/high sucrose (HF/HS) diet for 12 weeks. Changes in lipid composition were found in all strains after the HF/HS diet, most notably characterized by increases in monounsaturated fatty acids (MUFA) and decreases in polyunsaturated fatty acids (PUFA). Similar changes in MUFA and PUFA were observed in a choline- and folate-deficient (CFD) mouse model of NAFLD, as well as in hepatocytes treated in vitro with free fatty acids. Analysis of fatty acid composition revealed that alterations were accompanied by an increase in the estimated activity of MUFA generating SCD1 enzyme and an estimated decrease in the activity of PUFA generating FADS1 and FADS2 enzymes. PUFA/MUFA ratios were inversely correlated with lipid accumulation in male and female CC mice fed the HF/HS diet and with morphological markers of hepatic injury in CFD diet-fed mouse model of NAFLD. These results demonstrate that different models of NAFLD are characterized by similar changes in the esterified fatty acid composition and that alterations in PUFA/MUFA ratios may serve as a diagnostic marker for NAFLD severity. Show less

Toxicogenomic studies are increasingly used to uncover potential biomarkers of adverse health events, enrich chemical risk assessment, and to facilitate proper identification and treatment of persons susceptible to toxicity. Current approaches to biomarker discovery through gene expression profiling usually utilize a single or few strains of rodents, limiting the ability to detect biomarkers that may represent the wide range of toxicity responses typically observed in genetically heterogeneous human populations. To enhance the utility of animal models to detect response biomarkers for genetically diverse populations, we used a laboratory mouse strain diversity panel. Specifically, mice from 36 inbred strains derived from Mus mus musculus, Mus mus castaneous, and Mus mus domesticus origins were treated with a model hepatotoxic agent, acetaminophen (300 mg/kg, ig). Gene expression profiling was performed on liver tissue collected at 24 h after dosing. We identified 26 population-wide biomarkers of response to acetaminophen hepatotoxicity in which the changes in gene expression were significant across treatment and liver necrosis score but not significant for individual mouse strains. Importantly, most of these biomarker genes are part of the intracellular signaling involved in hepatocyte death and include genes previously associated with acetaminophen-induced hepatotoxicity, such as cyclin-dependent kinase inhibitor 1A (p21) and interleukin 6 signal transducer (Il6st), and genes not previously associated with acetaminophen, such as oncostatin M receptor (Osmr) and MLX interacting protein like (Mlxipl). Our data demonstrate that a multistrain approach may provide utility for understanding genotype-independent toxicity responses and facilitate identification of novel targets of therapeutic intervention. Show less

Juvenile neuronal ceroid lipofuscinosis (JNCL) belongs to the neuronal ceroid lipofuscinoses characterized by blindness/seizures/motor/cognitive decline and early death. JNCL is caused by CLN3 gene mutations that negatively modulate cell growth/apoptosis. CLN3 protein (CLN3p) localizes to Golgi/Rab4-/Rab11-positive endosomes and lipid rafts, and harbors a galactosylceramide (GalCer) lipid raft-binding domain. Goals are proving CLN3p participates in GalCer transport from Golgi to rafts, and GalCer deficits negatively affect cell growth/apoptosis. GalCer/mutant CLN3p are retained in Golgi, with CLN3p rescuing GalCer deficits in rafts. Diminishing GalCer in normal cells by GalCer synthase siRNA negatively affects cell growth/apoptosis. GalCer restores JNCL cell growth. WT CLN3p binds GalCer, but not mutant CLN3p. Sphingolipid content of rafts/Golgi is perturbed with diminished GalCer in rafts and accumulation in Golgi. CLN3-deficient raft vesicular structures are small by transmission electron microscopy, reflecting altered sphingolipid composition of rafts. CLN1/CLN2/CLN6 proteins bind to lysophosphatidic acid/sulfatide, CLN6/CLN8 proteins to GalCer, and CLN8 protein to ceramide. Sphingolipid composition/morphology of CLN1-/CLN2-/CLN6-/CLN8- and CLN9-deficient rafts are altered suggesting changes in raft structure/lipid stoichiometry could be common themes underlying these diseases. Show less