Expression Of Immune Response Genes Research Articles

NF-κB dynamics determine the stimulus specificity of epigenomic reprogramming in macrophages.

The epigenome of macrophages can be reprogrammed by extracellular cues, but the extent to which different stimuli achieve this is unclear. Nuclear factor κB (NF-κB) is a transcription factor that is activated by all pathogen-associated stimuli and can reprogram the epigenome by activating latent enhancers. However, we show that NF-κB does so only in response to a subset of stimuli. This stimulus specificity depends on the temporal dynamics of NF-κB activity, in particular whether it is oscillatory or non-oscillatory. Non-oscillatory NF-κB opens chromatin by sustained disruption of nucleosomal histone-DNA interactions, enabling activation of latent enhancers that modulate expression of immune response genes. Thus, temporal dynamics can determine a transcription factor's capacity to reprogram the epigenome in a stimulus-specific manner.

Acyl-CoA synthetase 6 is required for brain docosahexaenoic acid retention and neuroprotection during aging.

The omega-3 fatty acid docosahexaenoic acid (DHA) inversely relates to neurological impairments with aging; however, limited nondietary models manipulating brain DHA have hindered a direct linkage. We discovered that loss of long-chain acyl-CoA synthetase 6 in mice (Acsl6–/–) depletes brain membrane phospholipid DHA levels, independent of diet. Here, Acsl6–/– brains contained lower DHA compared with controls across the life span. The loss of DHA- and increased arachidonate-enriched phospholipids were visualized by MALDI imaging predominantly in neuron-rich regions where single-molecule RNA in situ hybridization localized Acsl6 to neurons. ACSL6 is also astrocytic; however, we found that astrocyte-specific ACSL6 depletion did not alter membrane DHA because astrocytes express a non–DHA-preferring ACSL6 variant. Across the life span, Acsl6–/– mice exhibited hyperlocomotion, impairments in working spatial memory, and increased cholesterol biosynthesis genes. Aging caused Acsl6–/– brains to decrease the expression of membrane, bioenergetic, ribosomal, and synaptic genes and increase the expression of immune response genes. With age, the Acsl6–/– cerebellum became inflamed and gliotic. Together, our findings suggest that ACSL6 promotes membrane DHA enrichment in neurons, but not in astrocytes, and is important for neuronal DHA levels across the life span. The loss of ACSL6 impacts motor function, memory, and age-related neuroinflammation, reflecting the importance of neuronal ACSL6-mediated lipid metabolism across the life span.

The impact of deoxynivalenol contaminated diet on performance, immune response, intestine morphology and jejunal gene expression in broiler chicken

The aim of this study was to determine the effects of deoxynivalenol (DON) contaminated diet on performance, immune system, gut morphology and jejunal gene expression in broiler chickens. Eighty-one-day old chicks were randomly allotted into two treatments with 4 replicates (10 birds in each replication). Experimental diets were the control diet (maize-soybean meal) and an experimentally contaminated diet with 10 mg/kg DON. The results indicated that DON-challenged birds had decreased (P < 0.05) average feed intake (AFI) during starter period as compared to control group. Also, average daily gain (ADG), AFI and feed conversion ratio (FCR) were not affected (P > 0.05) by inclusion of DON contaminated diet during the whole experimental period. Dietary addition of DON to the basal diet caused Fabricius bursa relative weight reduction, while increased the abdominal fat and serum triglyceride (TG) concentration (P < 0.05). Dietary DON feeding caused an enhancement (P < 0.05) in the blood aspartate aminotransferase (AST) and gamma glutamytransferase (GGT) contents. Moreover, DON decreased the serum total protein (TP) and albumin (ALB) concentrations. Inclusion of DON in diet reduced (P < 0.05) the white blood cell (WBC) count, lymphocyte number and antibody titer against Newcastle disease virus, but increased (P < 0.05) the blood heterophil count. The DON consumption also diminished (P < 0.05) the villus height, villus to crypt ratio, mucosa thickness and villus surface area in the duodenum. Mucin-2 expression was decreased (P < 0.05) by DON consumption, but toll-like receptor-4 (TLR-4) and claudin-5 (CLDN-5) expressions were not affected (P > 0.05) by dietary treatments. In conclusion, although DON could not influence the performance attributes in broiler chickens, it adversely affected the immune response, muc-2 gene expressions in the jejunum and gut morphology, enhanced the liver enzyme indices and lessened the blood protein contents.

Molecular and morphometric changes in the small intestine during hot and cold exposure in thermally manipulated broiler chickens.

Background and Aim:Thermal stress (hot or cold) is one of many environmental stressors that severely affects the health of broiler chickens. One negative effect of thermal stress is the disruption of the intestinal barrier function in broiler chickens. This study aimed to evaluate the effect of thermal manipulation (TM) on the small intestine in terms of histomorphometry as well as junctional, heat-shock, and immune response gene expression during post-hatch exposure to thermal stress.Materials and Methods:The experiment was conducted by dividing 928 fertile Ross eggs into three incubation groups: The control (C) group (incubated at 37.8°C and 56% relative humidity [RH] for the whole incubation period), the TM using low temperature TML group (incubated at 36°C and 56% RH for 18 h/day from embryonic days 7 to 16), and the TM using high temperature (TMH) group (incubated at 39°C and 65% RH for 18 h/day from embryonic days 7 to 16). On post-hatch day 21, 90 chicks were randomly selected from each incubation group and were equally subdivided into three subgroups for the post-hatch thermal stress experiment: The TN subgroup (room temperature maintained at 24°C), the heat stress (HS) subgroup (room temperature maintained at 35°C), and the cold stress (CS) subgroup (room temperature maintained at 16°C). After 1 day of thermal stress exposure (age 22 days), five birds from each subgroup were euthanized and ileum samples were collected to evaluate the transcription of the Claudin (CLDN1), CLDN-5, Occludin, Cadherin-1, heat shock factors (HSF1), HSF3, 70 kilodalton heat shock protein, 90 kilodalton heat shock protein, Interleukin 6 (IL6), IL8, toll-like receptors-2 (TLR2), and TLR4 genes by Real-Time Quantitative Reverse Transcription polymerase chain reaction analysis. Finally, after 4 and 7 days of thermal stress (age 25 and 28 days, respectively), nine chicks were euthanized, and their jejunum and ileum were collected for histomorphometric analysis.Results:After exposure to 1 day of thermal stress, the C subgroups exposed to thermal stress (HS and CS) possessed significantly increased expression of junctional, heat-shock, and immune response genes compared to the C-TN subgroup, and similar results were observed for the TMH. In contrast, thermally stressed TMH subgroups had significantly lower expression of the studied genes compared to C subgroups exposed to thermal stress. Furthermore, no significant changes were detected between the TML subgroups exposed to thermal stress and TML-TN. Moreover, significant alterations in villus height (VH), villus surface area, crypt depth (CD), and VH to CD ratio were observed between the TML, TMH, and C subgroups exposed to CS.Conclusion:It might be suggested that TM may have a protective impact on the small intestine histomorphometry and epithelial integrity of broilers during post-hatch exposure to thermal stress.

Effects of Probiotic and/or Prebiotic Supplementations on Immune Response, Haematology, Oxidant-antioxidant Biomarkers, and Cytokine mRNA Expression Levels in the Caeca of Broilers Infected with Salmonella

The present study was conducted to evaluate the effects of incorporation of the probiotic mix, prebiotic, and synbiotic supplements on immune response, interleukin-6, interleukin-10, and inducible nitric oxide synthase (iNOS) gene expression, hematology, and oxidant-antioxidant biomarkers of broilers infected with Salmonella Enteritidis and Salmonella Typhimurium mixed infection. A total of 273 commercial Cobb 500 chicks were randomly allocated into seven experimental groups, including NC group: fed only a basal diet (negative control), PC group; fed a basal diet and infected with Salmonellae on 3 rd life day (positive control), ProSa group: administrated probiotic mix in drinking water and then infected with Salmonellae, Presa group: fed prebiotic with basal diet and then infected with Salmonellae, SynSa: received probiotic mix and prebiotic (synbiotic) and then infected with Salmonellae, Pro group: given probiotic mix in feed, and Pre group: basal diet supplemented with prebiotic. The probiotic mix, prebiotic, and synbiotic supplementation significantly increased total IgY levels in the sera of infected birds in comparison to those of positive control. Also, the additives significantly downregulated IL-6 and iNOS gene expressions while they significantly upregulated IL-10 gene expression in the caeca of infected birds, in comparison to those of positive control. Also, the supplementary treatments significantly improved Salmonella-induced changes in hematology and oxidant-antioxidant biomarkers of infected groups. Compared with different supplementary treatments, the synbiotic significantly robust immune response of Salmonellainfected birds when compared with single supplementation of probiotic mix or prebiotic. In conclusion, probiotics, prebiotic, and in particular synbiotic supplements improved immune response, hematological and antioxidative biomarkers of birds experimentally infected with mixed Salmonellae.

SARS-CoV-2 infection, neuropathogenesis and transmission among deer mice: Implications for spillback to New World rodents.

Coronavirus disease-19 (COVID-19) emerged in late 2019 in China and rapidly became pandemic. As with other coronaviruses, a preponderance of evidence suggests the virus originated in horseshoe bats (Rhinolophus spp.) and may have infected an intermediate host prior to spillover into humans. A significant concern is that SARS-CoV-2 could become established in secondary reservoir hosts outside of Asia. To assess this potential, we challenged deer mice (Peromyscus maniculatus) with SARS-CoV-2 and found robust virus replication in the upper respiratory tract, lungs and intestines, with detectable viral RNA for up to 21 days in oral swabs and 6 days in lungs. Virus entry into the brain also occurred, likely via gustatory-olfactory-trigeminal pathway with eventual compromise to the blood-brain barrier. Despite this, no conspicuous signs of disease were observed, and no deer mice succumbed to infection. Expression of several innate immune response genes were elevated in the lungs, including IFNα, IFNβ, Cxcl10, Oas2, Tbk1 and Pycard. Elevated CD4 and CD8β expression in the lungs was concomitant with Tbx21, IFNγ and IL-21 expression, suggesting a type I inflammatory immune response. Contact transmission occurred from infected to naive deer mice through two passages, showing sustained natural transmission and localization into the olfactory bulb, recapitulating human neuropathology. In the second deer mouse passage, an insertion of 4 amino acids occurred to fixation in the N-terminal domain of the spike protein that is predicted to form a solvent-accessible loop. Subsequent examination of the source virus from BEI Resources determined the mutation was present at very low levels, demonstrating potent purifying selection for the insert during in vivo passage. Collectively, this work has determined that deer mice are a suitable animal model for the study of SARS-CoV-2 respiratory disease and neuropathogenesis, and that they have the potential to serve as secondary reservoir hosts in North America.

Effect of diet enriched with Agaricus bisporus polysaccharides (ABPs) on antioxidant property, innate-adaptive immune response and pro-anti inflammatory genes expression in Ctenopharyngodon idella against Aeromonas hydrophila

The effect of Agaricus bisporus polysaccharides (ABPs) supplemented diet on growth rate, antioxidant capacity, innate-adaptive immune response, proinflammatory and antiinflammatory genes expression in Ctenopharyngodon idella against Aeromonas hydrophila is reported. In both normal and challenged groups fed with 1.0 and 1.5 mg kg−1 ABPs diets resulted in a significant weight gain and feed intake. The survival was 100% in normal fish fed without or with any ABPs diet; the challenged fish fed with 1.0 mg kg−1 ABPs diet had 98.6% survival. The RBC and WBC counts, Hb, and Hct levels were significant in both normal and challenged groups fed with 1.0 and 1.5 mg kg−1 ABPs diets. A significant increase in total protein and albumin level was observed in both groups fed with 1.0 and 1.5 mg kg−1 ABPs diets. Significant increase in GPx, ROS, GR, GSH, PC, and MnSOD activity was observed in HK of both groups fed with 1.0 and 1.5 mg kg−1 ABPs diets; similarly both groups when fed with the same ABPs diets showed significant Lz, C3, and C4 activity. However, both groups fed with 1.0 mg kg−1 ABPs diet showed significant β-defensin, LEAP-2A, IL-6, and NF-κB P65 mRNA expression. Similarly, IFN-γ2, IL-10, and TNFα mRNA expressions were significant in both groups fed with 1.0 mg kg−1 ABPs diet. The results indicate that both normal and challenged C. idella fed with a 1.0 mg kg−1 ABPs diet had better growth, antioxidant status, immune response, and pro-anti-inflammatory gene modulation against A. hydrophila.

Studying the immune response genes expression regulation of Drosophila melanogaster

The main control of the synthesis of the antimicrobial peptides in the cells of Drosophila melanogaster is carried out by two signalling pathways IMD and Toll, which include the classic transcription factors of the NF-kB family (Dif, Dorsal and Relish). The Toll pathway is activated in response to gram-positive bacteria and fungi, and the IMD pathway is activated in response to gram-negative bacteria. In addition to transcription factors, the transcriptional apparatus of the cells includes the co-activators of transcription, such as the SAYP protein, which was described earlier in our laboratory. Co-activators do not bind directly to DNA, but assemble different parts of the transcriptional complex, which includes chromatin-remodelling complex, the specific transcription factors and the general transcription factors, which bind to RNA Pol II. SAYP homologues were found in the genomes of all multicellular animals. The protein mediates various functions of ontogenesis. We found that knockdown of SAYP leads to a decrease in expression of the specific genes of the IMD and Toll immune response pathways. In addition, the proteomic analysis of proteins associated with SAYP revealed sequences of another transcription factor, which is called DEAF-1. This protein is also involved in the immune response and ontogenesis. These prerequisites determined the task for studying the interactions of SAYP, Dif, Dorsal, Relish and DEAF-1 factors and their influence on the genes expression activation. We have obtained antibodies to the described factors. The most optimal epitopes (presumably exposed and accessible for recognition) were selected; the corresponding fragments of the cDNA genes were inserted into the expression vector and the conditions of expression in E.coli cells were matched. Recombinant proteins were produced and purified by metal-chelate affinity chromatography using Ni-Sepharose. The presence of these proteins in the fractions was confirmed by MALDI. The proteins have been used to immunize rabbits. The antibodies have been affinity purified from sera. The specificity of the antibodies was verified by Western blot analysis of the Drosophila embryonic nuclear extract. We have developed a model system for activating the IMD and Toll pathways. Escherichia coli and Micrococcus luteus cells were grown, washed and resuspended in water. The suspensions were inactivated and added to the S2 D. melanogaster cell cultures. Using qPCR, we have observed the activation of the immune response genes. Using the model system, we checked the recruitment of two model genes (Cecropin A1, Metchnikowin) to the promoters of the studied transcription co-activator. Chromatin immunoprecipitation has shown the binding of studied co-factor to gene promoters upon their activation. Immunoprecipitation using the obtained antibodies to DEAF-1 and SAYP has shown the co-precipitation of DEAF-1 protein with SAYP. This indicates that these proteins may jointly participate in the regulation of the immune response genes expression. We are currently looking for the individual domains of these proteins that mediate their interactions.

Immunogenetic determinants of heterosexual HIV-1 transmission: key findings and lessons from two distinct African cohorts.

Immunogenetic studies in the past three decades have uncovered a broad range of human genetic factors that seem to influence heterosexual HIV-1 transmission in one way or another. In our own work that jointly evaluated both genetic and non-genetic factors in two African cohorts of cohabiting, HIV-1-discordant couples (donor and recipient pairs) at risk of transmission during quarterly follow-up intervals, relatively consistent findings have been seen with three loci (IL19, HLA-A and HLA-B), although the effect size (i.e., odds ratio or hazards ratio) of each specific variant was quite modest. These studies offered two critical lessons that should benefit future research on sexually transmitted infections. First, in donor partners, immunogenetic factors (e.g., HLA-B*57 and HLA-A*36:01) that operate directly through HIV-1 viral load or indirectly through genital co-infections are equally important. Second, thousands of single nucleotide polymorphisms previously recognized as “causal” factors for human autoimmune disorders did not appear to make much difference, which is somewhat puzzling as these variants are predicted or known to influence the expression of many immune response genes. Replicating these observations in additional cohorts is no longer feasible as the field has shifted its focus to early diagnosis, universal treatment and active management of comorbidities.

HRSV nonstructural protein 1 (NS1) binds chromatin at regulatory regions of immune response genes.

Abstract Human respiratory syncytial virus (hRSV) causes severe acute respiratory tract infections in infants, elderly and immunocompromised people worldwide and few effective treatments are available. The hRSV nonstructural protein NS1 is known to inhibit host interferon responses in the cytoplasm. We and others have used in vitro interactome studies to identify host proteins that interact with NS1. Among these is the Mediator complex, a transcriptional coactivator localized in the nucleus, suggesting that NS1 may have a more direct role in modulating IFN-stimulated gene expression. We performed chromatin immunoprecipitation of NS1 or Mediator followed by sequencing (ChIP-seq) to map the genomic localization of hRSV NS1 or Mediator in A549 cells infected with hRSV or exogenously expressing hRSV-NS1. We identified 1756 NS1 binding sites, of which 82% (1442) of these are located within 10 KB of at least one gene. 42% (739 / 1756) of NS1 binding sites coincide with Mediator binding sites identified in the same cells, and 73% (1277 / 1756) overlap a known enhancer element (Enhancer Atlas). Moreover, NS1 binding sites often coincide with transcription factor binding sites in A549 cells (ENCODE). Comparison of RNA-seq from hRSV infected cells showed that nearly one-fourth of NS1 binding sites are located near genes significantly up- or down-regulated by hRSV infection. Moreover, these genes are enriched for IFN response genes. Finally, expression of NS1 reduced reporter gene expression when regulated by NS1-bound genetic elements. Together, our findings suggest that NS1 partially suppresses the expression of IFN immune response genes via directly interfering with transcriptional mechanisms, thereby contributing to immune evasion by hRSV.

The impacts of a fibrolytic enzyme additive on digestibility and performance in the grower and early finisher period, and supplementalSaccharomyces cerevisiaeon performance and rumen health in the late finisher period for feedlot cattle

Two experiments were conducted to determine the effects of a fibrolytic enzyme pretreatment on growth performance, apparent total tract digestibility, and ruminal pH throughout the grower and early finisher period (exp. 1), and to examine the impact of Saccharomyces cerevisiae supplementation on intake, performance, and indicators of gut health in the late finisher period (exp. 2). A total of 54 steers were randomly assigned to a subgroup determining experimental treatment groups. In exp. 1, steers were randomized to control (CON1; no enzyme) or enzyme [ENZ; 0.75 mL·kg−1dry matter (DM) of feed] dietary treatments. Digestibility was improved (P ≤ 0.05) in ENZ steers for DM, crude protein, net energy for gain, and sugars but did not affect (P ≥ 0.12) dry matter intake (DMI), average daily gain (ADG), or reticulo-ruminal pH. In exp. 2, the treatments were control (CON2; no yeast) or yeast (YST; 3.0 g·animal−1daily) supplemented diets. Rumen papillae were collected for mRNA expression of gut barrier function (OCLN, CLDN, ZO1, and ZO2) and immune response (TLR2, TLR4, and FCAR) genes and histological measurements. Yeast supplementation decreased (P &lt; 0.001) DMI by 31%, reduced variation in DMI, and improved feed conversion ratios but did not impact rumen health mRNA expression or histology measures (P ≥ 0.07). Overall, enzyme supplementation improved the digestibility of some nutrients in the grower period, and yeast supplementation improved feed efficiency, without impacting growth performance or gut health.

Cockroach-induced IL9, IL13, and IL31 expression and the development of allergic asthma in urban children

Cockroach-induced IL9, IL13, and IL31 expression and the development of allergic asthma in urban children

Selenium nanoparticle and selenomethionine as feed additives: effects on growth performance, hepatic enzymes' activity, mucosal immune parameters, liver histology, and appetite-related gene transcript in goldfish (Carassius auratus).

The aim of this study was to assess the effects of different dietary selenium sources, selenium nanoparticle (nSe), and selenomethionine (SeMet) as feed additives on growth performance, hepatic enzymes' activity, biochemical, mucosal immune parameters, liver histology, and appetite-related gene transcript in goldfish (Carassius auratus). At first, goldfish juveniles (n=480; mean 4.54 g) were fed dietary selenium nanoparticle at 0, 0.3, 0.6, and 0.9 mg nSe/kg diet and SeMet at 0, 0.3, 0.6, and 0.9 mg Se/kg for 9 weeks. Growth performance was evaluated using standard procedures. Blood, skin mucus, and tissue samples (liver and intestine) were collected for biochemical, mucosal immune response, histology, and ghrelin and insulin-like growth factor-I (IGF-I) gene expression. The results showed that fish fed diets fortified with 0.6 mg nSe/kg and 0.6 mg Se/kg had a significant higher weight gain, specific growth rates (SGR), and lower feed conversion ratios (FCR) than fish fed basal diets (p<0.05). Furthermore, dietary nSe and SeMet enhanced blood biochemical profiles especially alkaline phosphatase (ALP) (p < 0.05) and mucosal immunity than the control group in goldfish. Moreover, the liver histological investigation showed that fish fed 0.9 mg of SeMet and nSe kg-1 diets had higher liver lesion scores such as karyolysis, lipidosis, and hyperemia while fish fed 0, 0.3, and 0.6 mg of SeMet and nSe kg-1 diets had small liver changes at 9 weeks. The study further established that inclusion of nSe and SeMet in the diet of goldfish greatly promoted ghrelin and IGF-1genes expressions (p <0.05). Overall, dietary nSe performs better than SeMet and basal diets. The results evoked that nSe and SeMet stimulate the growth, biochemical, and mucosal immunity in goldfish at 0.6 mg/kg.

Abstract OT-26-04: Solti-1801. Analysis of the efficacy of CDK4/6 inhibitors in combination with hormonal treatment in luminal breast cancer in relation to the intrinsic subtype and markers of immunity (CDK-PREDICT)

Abstract Introduction. The incorporation of cyclin-dependent kinase inhibitors 4 and 6 (CDK4/6 inhibitors) with endocrine therapy in patients with advanced hormone receptor-positive (HR+) breast cancer and without overexpression of the HER2 (HER2-) oncogene has demonstrated its efficacy improving progression-free survival (PFS), overall response rate (ORR) and, more recently, overall survival (OS). However, patients eventually progress due to resistance to treatment. To date, no clinical or molecular markers defining the HR +/HER2- patient population that obtains the greatest benefit from these drugs have been found, apart from estrogen receptor positivity. However, there are data from multiple retrospective analysis suggesting that within HR+/ HER2- disease, the non-luminal intrinsic subtypes (20-30% of these patients) have a worse prognosis and may not benefit from CDK4/6 inhibitors. Furthermore, the prognostic impact of tumor infiltrating lymphocytes (TILs) and gene expression related to the immune response in the context of HR + / HER2- advanced breast cancer have not been deeply investigated. Design. CDK-PREDICT is an observational, non-interventional, multicenter study that will include 114 patients with advanced breast cancer who have received, are receiving or are going to receive endocrine therapy plus a CDK4/6 inhibitor for, at least, 8 weeks as first-line treatment. The primary objective is to correlate the intrinsic subtypes (defined by PAM50) with the efficacy (measured as PFS) of CDK4/6 inhibitors + hormone therapy. As secondary objectives, the correlation of the intrinsic subtypes with ORR and with the histopathological characteristics of the tumor will be analyzed. In addition, the expression of immune response and cell cycle genes, as well as the presence of TILs, will be correlated with the intrinsic subtypes and with PFS and ORR. Overall, we aim to develop a predictive score combining clinical, genomic and immune expression data integrating tumor biology and microenvironment. For inclusion in the study, a metastatic sample taken within 90 days prior to CDK4/6 inhibitors treatment will be required. Once this sample has been collected, registered and assessed for quality, patients will be followed up every 6 months until disease progression, death or withdrawal from the study. This project has received a research grant from “Instituto de Salud Carlos III (ISCIII), Ministerio de Economía y Competitividad” (Spain) awarded within the National Research Program with reference PI 18/01408, co-funded with European Union ERDF funds (European Regional Development Fund). This study is included within the Biomarker program of SOLTI. Recruitment of this study started in June 2020. Citation Format: Pablo Tolosa, Tomás Pascual, Cristina Hernando, Sonia Servitja, María Fernández Abad, Rafael Villanueva, Fernando Henao, Javier Benítez, Laura Lema, Mario Martínez, Yolanda Ruano, Lucía Parrilla, Alejandra Bernardini, Ana María Roncero, Laia Paré, Jordi Canes, Fernando Salvador, Patricia Villagrasa, Aleix Prat, Eva Ciruelos. Solti-1801. Analysis of the efficacy of CDK4/6 inhibitors in combination with hormonal treatment in luminal breast cancer in relation to the intrinsic subtype and markers of immunity (CDK-PREDICT) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-26-04.

Survival and gene expression responses in immune challenged larval lake sturgeon

Larval lake sturgeon, Acipenser fulvescens, reared in hatcheries for stock enhancement of wild populations may be susceptible to early opportunistic bacterial infection. Thus, we examined survival and whole-body mRNA expression of both stress- and immune-related genes (MyD88, IL-1β, StAR, GR1, and HSP70) in 30 days post fertilization larval lake sturgeon following immune challenge with lipopolysaccharides (LPS). Larval sturgeon were exposed to 0, 25, 50, 100, 150, and 200 μg ml−1 LPS and sampled after 30 min, 4 h, and 48 h. Mortality was zero in 0 and 25 μg ml−1 LPS; 37.5% in 50 μg ml−1 LPS and 100% in the higher concentrations. Expression of MyD88 and StAR mRNA were positively correlated and increased with time in the 50 μg ml−1 LPS treatment. There was an influence of both treatment and time on IL-1β mRNA, with expression 10-fold higher than controls after 4 h. Expression of HSP70 mRNA was suppressed within 30 min of 50 μg ml−1 LPS exposure and remained so throughout the time course. Correlated mRNA expression of GR1 with MyD88, StAR and IL-1β suggests a potential relationship between the innate immune and glucocorticoid responses of larval lake sturgeon during this early developmental stage. Data presented suggest that larval lake sturgeon largely responded with predicted changes in gene expression of immune related and stress response genes following LPS challenge. This study provides a foundation for future research examining the effects of hatchery and naturally occurring stressors on the immune responses of larval lake sturgeon.

Metabolic reprogramming and epigenetic changes of vital organs in SARS-CoV-2-induced systemic toxicity.

Extrapulmonary manifestations of COVID-19 are associated with a much higher mortality rate than pulmonary manifestations. However, little is known about the pathogenesis of systemic complications of COVID-19. Here, we create a murine model of SARS-CoV-2–induced severe systemic toxicity and multiorgan involvement by expressing the human ACE2 transgene in multiple tissues via viral delivery, followed by systemic administration of SARS-CoV-2. The animals develop a profound phenotype within 7 days with severe weight loss, morbidity, and failure to thrive. We demonstrate that there is metabolic suppression of oxidative phosphorylation and the tricarboxylic acid (TCA) cycle in multiple organs with neutrophilia, lymphopenia, and splenic atrophy, mirroring human COVID-19 phenotypes. Animals had a significantly lower heart rate, and electron microscopy demonstrated myofibrillar disarray and myocardial edema, a common pathogenic cardiac phenotype in human COVID-19. We performed metabolomic profiling of peripheral blood and identified a panel of TCA cycle metabolites that served as biomarkers of depressed oxidative phosphorylation. Finally, we observed that SARS-CoV-2 induces epigenetic changes of DNA methylation, which affects expression of immune response genes and could, in part, contribute to COVID-19 pathogenesis. Our model suggests that SARS-CoV-2–induced metabolic reprogramming and epigenetic changes in internal organs could contribute to systemic toxicity and lethality in COVID-19.

Protective Effects of Lactoferrin against SARS-CoV-2 Infection In Vitro.

SARS-CoV-2 is a newly emerging virus that currently lacks curative treatments. Lactoferrin (LF) is a naturally occurring non-toxic glycoprotein with broad-spectrum antiviral, immunomodulatory and anti-inflammatory effects. In this study, we assessed the potential of LF in the prevention of SARS-CoV-2 infection in vitro. Antiviral immune response gene expression was analyzed by qRT-PCR in uninfected Caco-2 intestinal epithelial cells treated with LF. An infection assay for SARS-CoV-2 was performed in Caco-2 cells treated or not with LF. SARS-CoV-2 titer was determined by qRT-PCR, plaque assay and immunostaining. Inflammatory and anti-inflammatory cytokine production was determined by qRT-PCR. LF significantly induced the expression of IFNA1, IFNB1, TLR3, TLR7, IRF3, IRF7 and MAVS genes. Furthermore, LF partially inhibited SARS-CoV-2 infection and replication in Caco-2 intestinal epithelial cells. Our in vitro data support LF as an immune modulator of the antiviral immune response with moderate effects against SARS-CoV-2 infection.

Uropathogenic Escherichia coli Virulence Factor α-Hemolysin Reduces Histone Acetylation to Inhibit Expression of Proinflammatory Cytokine Genes.

Urinary tract infections are common and costly diseases affecting millions of people. Uropathogenic Escherichia coli (UPEC) is a primary cause of these infections and has developed multiple strategies to avoid the host immune response. Here, we dissected the molecular mechanisms underpinning UPEC inhibition of inflammatory cytokine in vitro and in vivo. We found that UPEC infection simulates nuclear factor-κB activation but does not result in transcription of cytokine genes. Instead, UPEC-mediated suppression of the metabolic enzyme ATP citrate lyase results in decreased acetyl-CoA levels, leading to reduced H3K9 histone acetylation in the promotor region of CXCL8. These effects were dependent on the UPEC virulence factor α-hemolysin and were reversed by exogenous acetate. In a murine cystitis model, prior acetate supplementation rapidly resolved UPEC-elicited immune responses and improved tissue recovery. Thus, upon infection, UPEC rearranges host cell metabolism to induce chromatin remodeling processes that subvert expression of host innate immune response genes.

The Modulating Effect of Dietary Beta-Glucan Supplementation on Expression of Immune Response Genes of Broilers during a Coccidiosis Challenge

Simple SummaryAvian coccidiosis is the leading parasitic disease in the poultry industry and means to control its damages continue to be explored. This study evaluated the feeding effects of a yeast-derived β-glucan on expression of immune response genes in the spleen, thymus, and bursa of commercial broiler chickens during an Eimeria challenge. The study consisted of two dietary treatments (0% or 0.1% β-glucan) each with or without a coccidiosis challenge. There were significant effects from dietary β-glucan, Eimeria challenge, and their interaction for several gene targets in the spleen, thymus, and bursa on days 10 and 14 of age. Based on the current results, supplementation of dietary β-glucan in Eimeria-challenged birds enhanced and modulated the expression of immune response genes during coccidiosis.This study investigated the effects of a yeast-derived β-glucan (Auxoferm YGT) supplementation on mRNA expression of immune response genes in the spleen, thymus, and bursa of broiler chickens during a mixed Eimeria infection. Day (d)-old chicks (n = 1440) were fed diets containing 0% or 0.1% YGT. On d 8 post-hatch, half the replicate pens (n = 8) were challenged with a mixed inoculum of E. acervulina, E. maxima, and E. tenella. On d 10 and d 14 post-hatch, the spleen, thymus, and bursa were collected to evaluate mRNA abundance by quantitative real-time PCR. Data were analyzed using PROC GLIMMIX model (2-way interaction) and differences were established by LS-MEANS with significance reported at p ≤ 0.05. In spleen tissues at d 10, expression of interleukin (IL)-10 and inducible nitric oxide synthase (iNOS) were elevated in both 0.1% YGT-fed challenged and non-challenged birds. In thymus tissues at d 14, expression of IL-10, IL-17F, interferon (IFN)-γ, iNOS, and macrophage migration inhibitory factor (MIF) were elevated in challenged birds fed 0.1% YGT. In bursal tissues at d 10 and d 14, expression of IL-10, IFN-γ, iNOS (d 10 only), and MIF were elevated in 0.1% YGT-fed challenged and non-challenged birds. Dietary β-glucan supplementation to chicken diets modulated their immune response to the Eimeria challenge.

Comprehensive assessments of germline deletion structural variants reveal the association between prognostic MUC4 and CEP72 deletions and immune response gene expression in colorectal cancer patients

BackgroundFunctional disruptions by large germline genomic structural variants in susceptible genes are known risks for cancer. We used deletion structural variants (DSVs) generated from germline whole-genome sequencing (WGS) and DSV immune-related association tumor microenvironment (TME) to predict cancer risk and prognosis.MethodsWe investigated the contribution of germline DSVs to cancer susceptibility and prognosis by silicon and causal inference models. DSVs in germline WGS data were generated from the blood samples of 192 cancer and 499 non-cancer subjects. Clinical information, including family cancer history (FCH), was obtained from the National Cheng Kung University Hospital and Taiwan Biobank. Ninety-nine colorectal cancer (CRC) patients had immune response gene expression data. We used joint calling tools and an attention-weighted model to build the cancer risk predictive model and identify DSVs in familial cancer. The survival support vector machine (survival-SVM) was used to select prognostic DSVs.ResultsWe identified 671 DSVs that could predict cancer risk. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) of the attention-weighted model was 0.71. The 3 most frequent DSV genes observed in cancer patients were identified as ADCY9, AURKAPS1, and RAB3GAP2 (p < 0.05). The DSVs in SGSM2 and LHFPL3 were relevant to colorectal cancer. We found a higher incidence of FCH in cancer patients than in non-cancer subjects (p < 0.05). SMYD3 and NKD2DSV genes were associated with cancer patients with FCH (p < 0.05). We identified 65 immune-associated DSV markers for assessing cancer prognosis (p < 0.05). The functional protein of MUC4 DSV gene interacted with MAGE1 expression, according to the STRING database. The causal inference model showed that deleting the CEP72 DSV gene affect the recurrence-free survival (RFS) of IFIT1 expression.ConclusionsWe established an explainable attention-weighted model for cancer risk prediction and used the survival-SVM for prognostic stratification by using germline DSVs and immune gene expression datasets. Comprehensive assessments of germline DSVs can predict the cancer risk and clinical outcome of colon cancer patients.