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1.
PLoS Pathog ; 20(4): e1011939, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38683861

ABSTRACT

Epstein-Barr virus (EBV) persistently infects 95% of adults worldwide and is associated with multiple human lymphomas that express characteristic EBV latency programs used by the virus to navigate the B-cell compartment. Upon primary infection, the EBV latency III program, comprised of six Epstein-Barr Nuclear Antigens (EBNA) and two Latent Membrane Protein (LMP) antigens, drives infected B-cells into germinal center (GC). By incompletely understood mechanisms, GC microenvironmental cues trigger the EBV genome to switch to the latency II program, comprised of EBNA1, LMP1 and LMP2A and observed in GC-derived Hodgkin lymphoma. To gain insights into pathways and epigenetic mechanisms that control EBV latency reprogramming as EBV-infected B-cells encounter microenvironmental cues, we characterized GC cytokine effects on EBV latency protein expression and on the EBV epigenome. We confirmed and extended prior studies highlighting GC cytokine effects in support of the latency II transition. The T-follicular helper cytokine interleukin 21 (IL-21), which is a major regulator of GC responses, and to a lesser extent IL-4 and IL-10, hyper-induced LMP1 expression, while repressing EBNA expression. However, follicular dendritic cell cytokines including IL-15 and IL-27 downmodulate EBNA but not LMP1 expression. CRISPR editing highlighted that STAT3 and STAT5 were necessary for cytokine mediated EBNA silencing via epigenetic effects at the EBV genomic C promoter. By contrast, STAT3 was instead necessary for LMP1 promoter epigenetic remodeling, including gain of activating histone chromatin marks and loss of repressive polycomb repressive complex silencing marks. Thus, EBV has evolved to coopt STAT signaling to oppositely regulate the epigenetic status of key viral genomic promoters in response to GC cytokine cues.


Subject(s)
Epigenesis, Genetic , Epstein-Barr Virus Infections , Gene Expression Regulation, Viral , Germinal Center , Herpesvirus 4, Human , Virus Latency , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/physiology , Humans , Germinal Center/immunology , Germinal Center/virology , Epstein-Barr Virus Infections/virology , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/immunology , Cytokines/metabolism , B-Lymphocytes/virology , B-Lymphocytes/metabolism
2.
Future Oncol ; 18(11): 1391-1402, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35081733

ABSTRACT

Intrahepatic cholangiocarcinoma, a malignancy of the intrahepatic bile ducts, is the second most common primary liver malignancy and has been rising in incidence over the past several decades. Given its poor prognosis and diagnosis at a late stage, novel therapies are urgently needed to improve outcomes. Intrahepatic cholangiocarcinoma harbors a high rate of targetable mutations, spurring an increased interest in drug development in this disease. FGFR2 gene rearrangements occur in approximately 10-16% of these tumors and this underscores the importance of next generation sequencing in this population. There are now several FGFR inhibitors in development, and these agents may help improve outcomes for these patients. However, both primary and secondary resistance remain a challenge.


Intrahepatic cholangiocarcinoma is a type of cancer that occurs in the liver. This type of cancer is becoming increasingly common over the past several decades. New types of treatments are urgently needed to improve outcomes in this disease. Intrahepatic cholangiocarcinomas often have changes in their genetic makeup that may be used to help treat the disease. Changes in the FGFR2 occur in 10­16% of these tumors. There are now several US FDA approved medications that can help target this change in the tumor. However, these drugs may lose effectiveness after several months as the tumor may become resistant to the medication. There are new drugs currently in development that may be able to overcome this problem.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , Bile Duct Neoplasms/drug therapy , Bile Duct Neoplasms/genetics , Bile Ducts, Intrahepatic/pathology , Cholangiocarcinoma/drug therapy , Cholangiocarcinoma/genetics , Gene Rearrangement , Humans , Receptor, Fibroblast Growth Factor, Type 2/genetics
3.
Mol Microbiol ; 107(5): 610-622, 2018 03.
Article in English | MEDLINE | ID: mdl-29266479

ABSTRACT

Lignocellulose degradation by microbes plays a central role in global carbon cycling, human gut metabolism and renewable energy technologies. While considerable effort has been put into understanding the biochemical aspects of lignocellulose degradation, much less work has been done to understand how these enzymes work in an in vivo context. Here, we report a systems level study of xylan degradation in the saprophytic bacterium Cellvibrio japonicus. Transcriptome analysis indicated seven genes that encode carbohydrate active enzymes were up-regulated during growth with xylan containing media. In-frame deletion analysis of these genes found that only gly43F is critical for utilization of xylo-oligosaccharides, xylan, and arabinoxylan. Heterologous expression of gly43F was sufficient for the utilization of xylo-oligosaccharides in Escherichia coli. Additional analysis found that the xyn11A, xyn11B, abf43L, abf43K, and abf51A gene products were critical for utilization of arabinoxylan. Furthermore, a predicted transporter (CJA_1315) was required for effective utilization of xylan substrates, and we propose this unannotated gene be called xntA (xylan transporter A). Our major findings are (i) C. japonicus employs both secreted and surface associated enzymes for xylan degradation, which differs from the strategy used for cellulose degradation, and (ii) a single cytoplasmic ß-xylosidase is essential for the utilization of xylo-oligosaccharides.


Subject(s)
Bacterial Proteins/metabolism , Cellvibrio/enzymology , Cytoplasm/metabolism , Xylans/metabolism , Xylosidases/metabolism , Bacterial Proteins/genetics , Cellvibrio/genetics , Computer Simulation , Escherichia coli/enzymology , Escherichia coli/genetics , Fermentation , Gene Deletion , Gene Expression Profiling , Genes, Bacterial , Sequence Analysis, RNA , Xylosidases/genetics
4.
Clin Genet ; 95(2): 293-301, 2019 02.
Article in English | MEDLINE | ID: mdl-30417332

ABSTRACT

Telephone disclosure of cancer genetic test results is noninferior to in-person disclosure. However, how patients who prefer in-person communication of results differ from those who agree to telephone disclosure is unclear but important when considering delivery models for genetic medicine. Patients undergoing cancer genetic testing were recruited to a multicenter, randomized, noninferiority trial (NCT01736345) comparing telephone to in-person disclosure of genetic test results. We evaluated preferences for in-person disclosure, factors associated with this preference and outcomes compared to those who agreed to randomization. Among 1178 enrolled patients, 208 (18%) declined randomization, largely given a preference for in-person disclosure. These patients were more likely to be older (P = 0.007) and to have had multigene panel testing (P < 0.001). General anxiety (P = 0.007), state anxiety (P = 0.008), depression (P = 0.011), cancer-specific distress (P = 0.021) and uncertainty (P = 0.03) were higher after pretest counseling. After disclosure of results, they also had higher general anxiety (P = 0.003), depression (P = 0.002) and cancer-specific distress (P = 0.043). While telephone disclosure is a reasonable alternative to in-person disclosure in most patients, some patients have a strong preference for in-person communication. Patient age, distress and complexity of testing are important factors to consider and requests for in-person disclosure should be honored when possible.


Subject(s)
Communication , Hereditary Breast and Ovarian Cancer Syndrome/epidemiology , Neoplastic Syndromes, Hereditary/epidemiology , Patient Preference , Truth Disclosure , Adult , Aged , Biomarkers, Tumor , Female , Genetic Counseling/ethics , Genetic Counseling/methods , Genetic Predisposition to Disease , Genetic Testing/ethics , Hereditary Breast and Ovarian Cancer Syndrome/diagnosis , Hereditary Breast and Ovarian Cancer Syndrome/genetics , Humans , Male , Middle Aged , Neoplastic Syndromes, Hereditary/diagnosis , Neoplastic Syndromes, Hereditary/genetics , Outcome Assessment, Health Care , Patient Compliance , Telephone
5.
Breast Cancer Res Treat ; 153(3): 659-67, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26386956

ABSTRACT

Women living in rural areas of the U.S. face disparities in screening mammography and breast cancer outcomes. We sought to evaluate utilization of mammography, awareness of screening guidelines, and attitudes towards screening among rural insured U.S. women. We conducted a cross-sectional self-administered anonymous survey among 2000 women aged 40-64 insured by the National Rural Electric Cooperative Association, a non-profit insurer for electrical utility workers in predominantly rural areas across the U.S. Outcomes included mammographic screening in the past year, screening interval, awareness of guidelines, and perceived barriers to screening. 1588 women responded to the survey (response rate 79.4 %). 74 % of respondents lived in a rural area. Among women aged 40-49, 66.5 % reported mammographic screening in the past year. 46 % received annual screening, 32 % biennial screening, and 22 % rare/no screening. Among women aged 50-64, 77.1 % reported screening in the past year. 63 % received annual screening, 25 % biennial screening, and 12 % rare/no screening. The majority of women (98 %) believed that the mammography can find breast cancer early and save lives. Less than 1 % of younger women, and only 14 % of women over age 50 identified the recommendations of the U.S. Preventative Services Screening Task Force as the current expert recommendations for screening. Screening practices tended to follow perceived guideline recommendations. When rural U.S. women over age 40 have insurance, most receive breast cancer screening. The screening guidelines of cancer advocacy groups and specialty societies appear more influential and widely recognized than those of the U.S. preventative services taskforce.


Subject(s)
Breast Neoplasms/epidemiology , Early Detection of Cancer , Health Knowledge, Attitudes, Practice , Insurance, Health , Mass Screening , Patient Acceptance of Health Care , Practice Guidelines as Topic , Adult , Aged , Cross-Sectional Studies , Culture , Female , Health Surveys , Humans , Mammography , Middle Aged , Perception , Rural Population , Socioeconomic Factors , United States/epidemiology
6.
Diabetologia ; 57(11): 2282-95, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25091629

ABSTRACT

AIMS/HYPOTHESIS: Targeted metabolomic and transcriptomic approaches were used to evaluate the relationship between skeletal muscle metabolite signatures, gene expression profiles and clinical outcomes in response to various exercise training interventions. We hypothesised that changes in mitochondrial metabolic intermediates would predict improvements in clinical risk factors, thereby offering novel insights into potential mechanisms. METHODS: Subjects at risk of metabolic disease were randomised to 6 months of inactivity or one of five aerobic and/or resistance training programmes (n = 112). Pre/post-intervention assessments included cardiorespiratory fitness ([Formula: see text]), serum triacylglycerols (TGs) and insulin sensitivity (SI). In this secondary analysis, muscle biopsy specimens were used for targeted mass spectrometry-based analysis of metabolic intermediates and measurement of mRNA expression of genes involved in metabolism. RESULTS: Exercise regimens with the largest energy expenditure produced robust increases in muscle concentrations of even-chain acylcarnitines (median 37-488%), which correlated positively with increased expression of genes involved in muscle uptake and oxidation of fatty acids. Along with free carnitine, the aforementioned acylcarnitine metabolites were related to improvements in [Formula: see text], TGs and SI (R = 0.20-0.31, p < 0.05). Muscle concentrations of the tricarboxylic acid cycle intermediates succinate and succinylcarnitine (R = 0.39 and 0.24, p < 0.05) emerged as the strongest correlates of SI. CONCLUSIONS/INTERPRETATION: The metabolic signatures of exercise-trained skeletal muscle reflected reprogramming of mitochondrial function and intermediary metabolism and correlated with changes in cardiometabolic fitness. Succinate metabolism and the succinate dehydrogenase complex emerged as a potential regulatory node that intersects with whole-body insulin sensitivity. This study identifies new avenues for mechanistic research aimed at understanding the health benefits of physical activity. Trial registration ClinicalTrials.gov NCT00200993 and NCT00275145 Funding This work was supported by the National Heart, Lung, and Blood Institute (National Institutes of Health), National Institute on Aging (National Institutes of Health) and National Institute of Arthritis and Musculoskeletal and Skin Diseases (National Institutes of Health).


Subject(s)
Exercise/physiology , Mitochondria, Muscle/metabolism , Muscle, Skeletal/metabolism , Adolescent , Adult , Aged , Amino Acids, Branched-Chain/metabolism , Carnitine/analogs & derivatives , Carnitine/metabolism , Female , Humans , Male , Metabolomics , Middle Aged , Succinic Acid/metabolism , Young Adult
7.
bioRxiv ; 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38260430

ABSTRACT

Epstein-Barr virus (EBV) persistently infects 95% of adults worldwide and is associated with multiple human lymphomas that express characteristic EBV latency programs used by the virus to navigate the B-cell compartment. Upon primary infection, the EBV latency III program, comprised of six Epstein-Barr Nuclear Antigens (EBNA) and two Latent Membrane Protein (LMP) antigens, drives infected B-cells into germinal center (GC). By incompletely understood mechanisms, GC microenvironmental cues trigger the EBV genome to switch to the latency II program, comprised of EBNA1, LMP1 and LMP2A and observed in GC-derived Hodgkin lymphoma. To gain insights into pathways and epigenetic mechanisms that control EBV latency reprogramming as EBV-infected B-cells encounter microenvironmental cues, we characterized GC cytokine effects on EBV latency protein expression and on the EBV epigenome. We confirmed and extended prior studies highlighting GC cytokine effects in support of the latency II transition. The T-follicular helper cytokine interleukin 21 (IL-21), which is a major regulator of GC responses, and to a lesser extent IL-4 and IL-10, hyper-induced LMP1 expression, while repressing EBNA expression. However, follicular dendritic cell cytokines including IL-15 and IL-27 downmodulate EBNA but not LMP1 expression. CRISPR editing highlighted that STAT3 and STAT5 were necessary for cytokine mediated EBNA silencing via epigenetic effects at the EBV genomic C promoter. By contrast, STAT3 was instead necessary for LMP1 promoter epigenetic remodeling, including gain of activating histone chromatin marks and loss of repressive polycomb repressive complex silencing marks. Thus, EBV has evolved to coopt STAT signaling to oppositely regulate the epigenetic status of key viral genomic promoters in response to GC cytokine cues.

8.
Cancer Immunol Res ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990554

ABSTRACT

Innate inflammation promotes tumor development, although the role of innate inflammatory cytokines in established human tumors is unclear. Here we report clinical and translational results from a phase Ib trial testing whether IL-1ß blockade in human pancreatic cancer would alleviate myeloid immunosuppression and reveal antitumor T-cell responses to PD-1 blockade. Patients with treatment-naïve advanced pancreatic ductal adenocarcinoma (n=10) were treated with canakinumab, a high-affinity monoclonal human anti-interleukin-1ß (IL-1ß), the PD-1 blocking antibody spartalizumab, and gemcitabine/n(ab)paclitaxel. Analysis of paired peripheral blood from patients in the trial versus patients receiving multiagent chemotherapy showed a modest increase in HLA-DR+CD38+ activated CD8+ T cells and a decrease in circulating monocytic myeloid-derived suppressor cells (MDSCs) by flow cytometry for patients in the trial, but not in controls. Similarly, we used patient serum to differentiate monocytic MDSCs in vitro and showed that functional inhibition of T-cell proliferation was reduced when using on-treatment serum samples from patients in the trial but not when using serum from patients treated with chemotherapy alone. Within the tumor we observed few changes in suppressive myeloid-cell populations or activated T cells as assessed by single-cell transcriptional profiling or multiplex immunofluorescence, although increases in CD8+ T cells suggest that improvements in the tumor immune microenvironment might be revealed by a larger study. Overall, the data indicate that exposure to PD-1 and IL-1ß blockade induced a modest reactivation of peripheral CD8+ T cells and decreased circulating monocytic MDSCs; however, these changes did not lead to similarly uniform alterations in the tumor microenvironment.

9.
Immunotherapy ; 15(7): 541-551, 2023 05.
Article in English | MEDLINE | ID: mdl-37096964

ABSTRACT

Cholangiocarcinoma is an epithelial malignancy originating in the biliary tracts and frequently recurs even with surgical resection. Unresectable disease has a 5-year overall survival of less than 10%. Given this poor prognosis, additional therapies are urgently needed. Chemotherapy has been the mainstay of treatment for many years. However, with the incorporation of immunotherapy into the treatment of other malignancies, there has been a great deal of interest in immunotherapy for biliary cancers. Recently, durvalumab was approved in combination with gemcitabine and cisplatin for the treatment of unresectable cholangiocarcinoma in the first-line setting. However, predicting which patients may respond to immunotherapy remains a challenge due to the lack of a reliable biomarker.


Cholangiocarcinoma is a type of cancer that originates in the bile ducts. Unfortunately, this tumor has a poor prognosis and frequently recurs despite surgical resection. Therefore, there is an urgent need to develop additional therapies. Immunotherapy has been integrated into the treatment of multiple types of cancers, and there is interest in integrating immunotherapy into the treatment of biliary cancers as well. Most recently, the TOPAZ-1 study led to the approval of durvalumab added to gemcitabine and cisplatin chemotherapy. There are additional ongoing studies evaluating the use of combination immunotherapies, local therapies such as radiation plus immunotherapy as well as other multimodality treatments.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , Humans , Immune Checkpoint Inhibitors/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Cholangiocarcinoma/drug therapy , Bile Duct Neoplasms/drug therapy , Bile Ducts, Intrahepatic/pathology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
10.
bioRxiv ; 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37090591

ABSTRACT

The Epstein-Barr virus (EBV) oncogene latent membrane protein 1 (LMP1) mimics CD40 signaling and is expressed by multiple malignancies. Two LMP1 C-terminal cytoplasmic tail regions, termed transformation essential sites (TES) 1 and 2, are critical for EBV transformation of B lymphocytes into immortalized lymphoblastoid cell lines (LCL). However, TES1 versus TES2 B-cell target genes have remained incompletely characterized, and whether both are required for LCL survival has remained unknown. To define LCL LMP1 target genes, we profiled transcriptome-wide effects of acute LMP1 CRISPR knockout (KO) prior to cell death. To then characterize specific LCL TES1 and TES2 roles, we conditionally expressed wildtype, TES1 null, TES2 null or double TES1/TES2 null LMP1 alleles upon endogenous LMP1 KO. Unexpectedly, TES1 but not TES2 signaling was critical for LCL survival. The LCL dependency factor cFLIP, which plays obligatory roles in blockade of LCL apoptosis, was highly downmodulated by loss of TES1 signaling. To further characterize TES1 vs TES2 roles, we conditionally expressed wildtype, TES1 and/or TES2 null LMP1 alleles in two Burkitt models. Systematic RNAseq analyses revealed gene clusters that responded more strongly to TES1 versus TES2, that respond strongly to both or that are oppositely regulated. Robust TES1 effects on cFLIP induction were again noted. TES1 and 2 effects on expression of additional LCL dependency factors, including BATF and IRF4, and on EBV super-enhancers were identified. Collectively, these studies suggest a model by which LMP1 TES1 and TES2 jointly remodel the B-cell transcriptome and highlight TES1 as a key therapeutic target.

11.
mBio ; : e0233823, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38009935

ABSTRACT

IMPORTANCE: Epstein-Barr virus (EBV) causes multiple human cancers, including B-cell lymphomas. In cell culture, EBV converts healthy human B-cells into immortalized ones that grow continuously, which model post-transplant lymphomas. Constitutive signaling from two cytoplasmic tail domains of the EBV oncogene latent membrane protein 1 (LMP1) is required for this transformation, yet there has not been systematic analysis of their host gene targets. We identified that only signaling from the membrane proximal domain is required for survival of these EBV-immortalized cells and that its loss triggers apoptosis. We identified key LMP1 target genes, whose abundance changed significantly with loss of LMP1 signals, or that were instead upregulated in response to switching on signaling by one or both LMP1 domains in an EBV-uninfected human B-cell model. These included major anti-apoptotic factors necessary for EBV-infected B-cell survival. Bioinformatics analyses identified clusters of B-cell genes that respond differently to signaling by either or both domains.

12.
Cancer Med ; 12(3): 2345-2355, 2023 02.
Article in English | MEDLINE | ID: mdl-35906821

ABSTRACT

BACKGROUND: Genetic testing is recommended for all pancreatic ductal adenocarcinoma (PDAC) patients. Prior research demonstrates that multidisciplinary pancreatic cancer clinics (MDPCs) improve treatment- and survival-related outcomes for PDAC patients. However, limited information exists regarding the utility of integrated genetics in the MDPC setting. We hypothesized that incorporating genetics in an MDPC serving both PDAC patients and high-risk individuals (HRI) could: (1) improve compliance with guideline-based genetic testing for PDAC patients, and (2) optimize HRI identification and PDAC surveillance participation to improve early detection and survival. METHODS: Demographics, genetic testing results, and pedigrees were reviewed for PDAC patients and HRI at one institution over 45 months. Genetic testing analyzed 16 PDAC-associated genes at minimum. RESULTS: Overall, 969 MDPC subjects were evaluated during the study period; another 56 PDAC patients were seen outside the MDPC. Among 425 MDPC PDAC patients, 333 (78.4%) completed genetic testing; 29 (8.7%) carried a PDAC-related pathogenic germline variant (PGV). Additionally, 32 (9.6%) met familial pancreatic cancer (FPC) criteria. These PDAC patients had 191 relatives eligible for surveillance or genetic testing. Only 2/56 (3.6%) non-MDPC PDAC patients completed genetic testing (p < 0.01). Among 544 HRI, 253 (46.5%) had a known PGV or a designation of FPC, and were eligible for surveillance at baseline; of the remainder, 15/291 (5.2%) were eligible following genetic testing and PGV identification. CONCLUSION: Integrating genetics into the multidisciplinary setting significantly improved genetic testing compliance by reducing logistical barriers for PDAC patients, and clarified cancer risks for their relatives while conserving clinical resources. Overall, we identified 206 individuals newly eligible for surveillance or genetic testing (191 relatives of MDPC PDAC patients, and 15 HRI from this cohort), enabling continuity of care for PDAC patients and at-risk relatives in one clinic.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Genetic Predisposition to Disease , Pancreatic Neoplasms/pathology , Genetic Testing , Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms
13.
Nat Commun ; 14(1): 797, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36781852

ABSTRACT

The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) is a complex ecosystem that drives tumor progression; however, in-depth single cell characterization of the PDAC TME and its role in response to therapy is lacking. Here, we perform single-cell RNA sequencing on freshly collected human PDAC samples either before or after chemotherapy. Overall, we find a heterogeneous mixture of basal and classical cancer cell subtypes, along with distinct cancer-associated fibroblast and macrophage subpopulations. Strikingly, classical and basal-like cancer cells exhibit similar transcriptional responses to chemotherapy and do not demonstrate a shift towards a basal-like transcriptional program among treated samples. We observe decreased ligand-receptor interactions in treated samples, particularly between TIGIT on CD8 + T cells and its receptor on cancer cells, and identify TIGIT as the major inhibitory checkpoint molecule of CD8 + T cells. Our results suggest that chemotherapy profoundly impacts the PDAC TME and may promote resistance to immunotherapy.


Subject(s)
Adenocarcinoma , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Adenocarcinoma/drug therapy , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Tumor Microenvironment/genetics , Ecosystem , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Sequence Analysis, RNA , Pancreatic Neoplasms
14.
Cell Rep ; 37(2): 109803, 2021 10 12.
Article in English | MEDLINE | ID: mdl-34644581

ABSTRACT

Human respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections in the pediatric, elderly, and immunocompromised individuals. RSV non-structural protein NS1 is a known cytosolic immune antagonist, but how NS1 modulates host responses remains poorly defined. Here, we observe NS1 partitioning into the nucleus of RSV-infected cells, including the human airway epithelium. Nuclear NS1 coimmunoprecipitates with Mediator complex and is chromatin associated. Chromatin-immunoprecipitation demonstrates enrichment of NS1 that overlaps Mediator and transcription factor binding within the promoters and enhancers of differentially expressed genes during RSV infection. Mutation of the NS1 C-terminal helix reduces NS1 impact on host gene expression. These data suggest that nuclear NS1 alters host responses to RSV infection by binding at regulatory elements of immune response genes and modulating host gene transcription. Our study identifies another layer of regulation by virally encoded proteins that shapes host response and impacts immunity to RSV.


Subject(s)
Cell Nucleus/metabolism , Chromatin/metabolism , Dendritic Cells/metabolism , Epithelial Cells/metabolism , Lung/metabolism , Respiratory Syncytial Virus Infections/metabolism , Respiratory Syncytial Virus, Human/metabolism , Transcription, Genetic , Viral Nonstructural Proteins/metabolism , A549 Cells , Animals , Binding Sites , Cell Nucleus/virology , Chromatin/genetics , Chromatin/virology , Dendritic Cells/virology , Epithelial Cells/virology , Female , HEK293 Cells , Host-Pathogen Interactions , Humans , Lung/virology , Mediator Complex/genetics , Mediator Complex/metabolism , Mice, Inbred BALB C , Promoter Regions, Genetic , Respiratory Syncytial Virus Infections/genetics , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Virus, Human/pathogenicity , Viral Nonstructural Proteins/genetics
16.
J Microbiol Methods ; 130: 136-143, 2016 11.
Article in English | MEDLINE | ID: mdl-27664455

ABSTRACT

Physiological studies of recalcitrant polysaccharide degradation are challenging for several reasons, one of which is the difficulty in obtaining a reproducibly accurate real-time measurement of bacterial growth using insoluble substrates. Current methods suffer from several problems including (i) high background noise due to the insoluble material interspersed with cells, (ii) high consumable and reagent cost and (iii) significant time delay between sampling and data acquisition. A customizable substrate and cell separation device would provide an option to study bacterial growth using optical density measurements. To test this hypothesis we used 3-D printing to create biomass containment devices that allow interaction between insoluble substrates and microbial cells but do not interfere with spectrophotometer measurements. Evaluation of materials available for 3-D printing indicated that UV-cured acrylic plastic was the best material, being superior to nylon or stainless steel when examined for heat tolerance, reactivity, and ability to be sterilized. Cost analysis of the 3-D printed devices indicated they are a competitive way to quantitate bacterial growth compared to viable cell counting or protein measurements, and experimental conditions were scalable over a 100-fold range. The presence of the devices did not alter growth phenotypes when using either soluble substrates or insoluble substrates. We applied biomass containment to characterize growth of Cellvibrio japonicus on authentic lignocellulose (non-pretreated corn stover), and found physiological evidence that xylan is a significant nutritional source despite an abundance of cellulose present.


Subject(s)
Bacteria/growth & development , Biomass , Equipment Contamination , Printing, Three-Dimensional/instrumentation , Solubility , Bacteria/metabolism , Carbohydrate Metabolism , Cellulose/metabolism , Cellvibrio/genetics , Cellvibrio/growth & development , Cellvibrio/metabolism , Equipment Design/economics , Equipment Design/instrumentation , Lignin/chemistry , Microbial Viability , Mutation , Nylons/chemistry , Spectrophotometry , Stainless Steel/chemistry , Sterilization , Xylans/metabolism , Zea mays/chemistry
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