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Beane J.,Boston University | Vick J.,Boston University | Schembri F.,Boston University | Anderlind C.,Boston University | And 11 more authors.
Cancer Prevention Research | Year: 2011

Cigarette smoke creates a molecular field of injury in epithelial cells that line the respiratory tract. We hypothesized that transcriptome sequencing (RNA-Seq) will enhance our understanding of the field of molecular injury in response to tobacco smoke exposure and lung cancer pathogenesis by identifying gene expression differences not interrogated or accurately measured by microarrays. We sequenced the highmolecular-weight fraction of total RNA (>200 nt) from pooled bronchial airway epithelial cell brushings (n = 3 patients per pool) obtained during bronchoscopy from healthy never smoker (NS) and current smoker (S) volunteers and smokers with (C) and without (NC) lung cancer undergoing lung nodule resection surgery. RNA-Seq libraries were prepared using 2 distinct approaches, one capable of capturing non-polyadenylated RNA (the prototype NuGEN Ovation RNA-Seq protocol) and the other designed to measure only polyadenylated RNA (the standard Illumina mRNA-Seq protocol) followed by sequencing generating approximately 29 million 36 nt reads per pool and approximately 22 million 75 nt paired-end reads per pool, respectively. The NuGEN protocol captured additional transcripts not detected by the Illumina protocol at the expense of reduced coverage of polyadenylated transcripts, while longer read lengths and a paired-end sequencing strategy significantly improved the number of reads that could be aligned to the genome. The aligned reads derived from the two complementary protocols were used to define the compendium of genes expressed in the airway epithelium (n = 20,573 genes). Pathways related to the metabolism of xenobiotics by cytochrome P450, retinol metabolism, and oxidoreductase activity were enriched among genes differentially expressed in smokers, whereas chemokine signaling pathways, cytokine-cytokine receptor interactions, and cell adhesion molecules were enriched among genes differentially expressed in smokers with lung cancer. There was a significant correlation between the RNA-Seq gene expression data and Affymetrix microarray data generated from the same samples (P < 0.001); however, the RNA-Seq data detected additional smoking- and cancer-related transcripts whose expression was were either not interrogated by or was not found to be significantly altered when using microarrays, including smokingrelated changes in the inflammatory genes S100A8 and S100A9 and cancer-related changes in MUC5AC and secretoglobin (SCGB3A1). Quantitative real-time PCR confirmed differential expression of select genes and non-coding RNAs within individual samples. These results demonstrate that transcriptome sequencing has the potential to provide new insights into the biology of the airway field of injury associated with smoking and lung cancer. The measurement of both coding and non-coding transcripts by RNA-Seq has the potential to help elucidate mechanisms of response to tobacco smoke and to identify additional biomarkers of lung cancer risk and novel targets for chemoprevention. ©2011 AACR. Source

Majerczyk C.,University of Washington | Brittnacher M.,University of Washington | Jacobs M.,University of Washington | Armour C.D.,NuGEN | And 5 more authors.
Journal of Bacteriology | Year: 2014

Burkholderia thailandensis contains three acyl-homoserine lactone quorum sensing circuits and has two additional LuxR homologs. To identify B. thailandensis quorum sensing-controlled genes, we carried out transcriptome sequencing (RNA-seq) analyses of quorum sensing mutants and their parent. The analyses were grounded in the fact that we identified genes coding for factors shown previously to be regulated by quorum sensing among a larger set of quorum-controlled genes. We also found that genes coding for contact-dependent inhibition were induced by quorum sensing and confirmed that specific quorum sensing mutants had a contact-dependent inhibition defect. Additional quorum-controlled genes included those for the production of numerous secondary metabolites, an uncharacterized exopolysaccharide, and a predicted chitin-binding protein. This study provides insights into the roles of the three quorum sensing circuits in the saprophytic lifestyle of B. thailandensis, and it provides a foundation on which to build an understanding of the roles of quorum sensing in the biology of B. thailandensis and the closely related pathogenic Burkholderia pseudomallei and Burkholderia mallei. © 2014, American Society for Microbiology. Source

Majerczyk C.D.,University of Washington | Brittnacher M.J.,University of Washington | Jacobs M.A.,University of Washington | Armour C.D.,NuGEN | And 5 more authors.
Journal of Bacteriology | Year: 2014

Burkholderia pseudomallei, Burkholderia thailandensis, and Burkholderia mallei (the Bptm group) are close relatives with very different lifestyles: B. pseudomallei is an opportunistic pathogen, B. thailandensis is a nonpathogenic saprophyte, and B. mallei is a host-restricted pathogen. The acyl-homoserine lactone quorum-sensing (QS) systems of these three species show a high level of conservation. We used transcriptome sequencing (RNA-seq) to define the quorum-sensing regulon in each species, and we performed a cross-species analysis of the QS-controlled orthologs. Our analysis revealed a core set of QS-regulated genes in all three species, as well as QS-controlled factors shared by only two species or unique to a given species. This global survey of the QS regulons of B. pseudomallei, B. thailandensis, and B. mallei serves as a platform for predicting which QS-controlled processes might be important in different bacterial niches and contribute to the pathogenesis of B. pseudomallei and B. mallei. © 2014, American Society for Microbiology. Source

News Article
Site: http://www.nature.com/nature/current_issue/

All mice were maintained on a C57BL/6 background, including ScfGFP (ref. 19), Scffl/+ (ref. 19), Cxcl12DsRed (ref. 18), Cxcl12fl/+ (ref. 18), R26tdTomato (ref. 26), Vav1-cre (ref. 24), Leprcre (ref. 27), Tcf21cre/ER (ref. 21) and α-catulinGFP. To induce Cre/ER activity in Tcf21cre/ER mice, 4–6-week-old mice were administered 2 mg tamoxifen (Sigma) daily by oral gavage for 12 consecutive days. For induction of EMH, mice were injected at day 0 with a single dose of 4 mg cyclophosphamide followed by daily injections of 5 μg G-CSF for 4–21 days. Both male and female mice were used. All mice were housed in the Animal Resource Center at the University of Texas Southwestern Medical Center (UTSW). All procedures were approved by the UTSW Institutional Animal Care and Use Committee. Bone marrow cells were isolated by flushing the femur or tibia with Ca2+- and Mg2+-free HBSS with 2% heat-inactivated bovine serum using a 3 ml syringe fitted with a 25-gauge needle. Spleen cells were obtained by crushing the spleen between two frosted slides. The cells were dissociated to a single-cell suspension by gently passing through the needle several times and then filtering through a 40-μm nylon mesh. Blood was collected by cardiac puncture, and white blood cells were isolated by ficoll centrifugation according to the manufacturer’s instructions (GE Healthcare). The following antibodies were used to isolate HSCs: anti-CD150 (TC15-12F12.2), anti-CD48 (HM48-1), anti-Sca-1 (E13-161.7), anti-c-kit (2B8) and the following antibodies against lineage markers (anti-Ter119, anti-B220 (6B2), anti-Gr-1 (8C5), anti-CD2 (RM2-5), anti-CD3 (17A2), anti-CD5 (53-7.3) and anti-CD8 (53-6.7)). Haematopoietic progenitors were identified by flow cytometry using the following antibodies: anti-Sca-1 (E13-161.7), anti-c-Kit (2B8) and the following antibodies against lineage markers (anti-Ter119, anti-B220 (6B2), anti-Gr-1 (8C5), anti-CD2 (RM2-5), anti-CD3 (17A2), anti-CD5 (53-7.3) and anti-CD8 (53-6.7)), anti-CD34 (RAM34), anti-CD135 (Flt3) (A2F10), anti-CD16/32 (FcγR) (93), anti-CD127 (IL7Rα) (A7R34), anti-CD24 (M1/69), anti-CD43 (1B11), anti-B220 (6B2), anti-IgM (II/41), anti-CD3 (17A2), anti-Gr-1 (8C5), anti-Mac-1 (M1/70), anti-CD41 (MWReg30), anti-CD71 (C2) and anti-Ter119. 4′,6-Diamidino-2-phenylindole (DAPI) was used to exclude dead cells. Antibodies were obtained from eBioscience or BD Bioscience. To isolate bone marrow stromal cells the marrow was gently flushed out of the bone marrow cavity with a 3-ml syringe fitted with a 23-guage needle and then transferred into 1 ml pre-warmed bone marrow digestion solution (200 U ml−1 DNase I (Sigma), 250 μg ml−1 LiberaseDL (Roche) in HBSS plus Ca2+ and Mg2+) and incubated at 37 °C for 30 min with gentle shaking. To isolate splenic stromal cells, the spleen capsule was cut into ~1 mm3 fragments using scissors and then digested as described earlier in spleen digestion solution (200 U ml−1 DNase I, 250 μg ml−1 LiberaseDL, 1 mg ml−1 collagenase, type 4 (Roche) and 500 μg ml−1 collagenase D (Roche) in HBSS plus Ca2+ and Mg2+). After a brief vortex, the spleen fragments were allowed to sediment for ~3 min and the supernatant was transferred to another tube on ice. The sedimented (undigested) spleen fragments were subjected to a second round of digestion. The two fractions of digested cells were pooled and filtered through a 100-μm nylon mesh. Anti-PDGFR-α (APA5), anti-PDGFR-β (APB5), anti-LepR (R&D), anti-CD45 (30F-11) and anti-Ter119 antibodies were used to isolate stromal cells. For analysis of endothelial cells, mice were injected intravenously into the retro-orbital venous sinus with 10 μg Alexa-Fluor-660-conjugated anti-VE-cadherin antibody (BV13) 10 min before being killed. Samples were analysed using a FACSAria or FACSCanto II flow cytometer (BD Biosciences). To assess BrdU incorporation into spleen cells after EMH induction, mice were intraperitoneally injected with a single dose of BrdU (2 mg BrdU per mouse) then maintained on 0.5 mg BrdU per ml drinking water for 7 days. Endothelial cells were labelled by intravenous injection of an anti-VE-cadherin antibody (eBioscience). Enzymatically dissociated spleen cells were stained with antibodies against surface markers and the target cell populations were sorted then resorted to ensure purity. The sorted cells were then fixed, and stained with an anti-BrdU antibody using the BrdU APC Flow Kit (BD Biosciences) according to the manufacturer’s instructions. Adult recipient mice were irradiated using an XRAD 320 X-ray irradiator (Precision X-Ray) with two doses of 540 rad (total 1,080 rad) delivered at least 2 h apart. Cells were injected into the retro-orbital venous sinus of anaesthetized mice. Sorted doses of splenocytes from donor mice with EMH were transplanted along with 3 × 105 recipient bone marrow cells. Recipient mice were bled every 4 weeks to assess the level of donor-derived blood cells, including myeloid, B and T cells for at least 16 weeks. Blood was subjected to ammonium chloride/potassium red cell lysis before antibody staining. Antibodies including anti-CD45.2 (104), anti-CD45.1 (A20), anti-Gr1 (8C5), anti-Mac-1 (M1/70), anti-B220 (6B2) and anti-CD3 (KT31.1) were used for flow cytometric analysis. For bone marrow sections, freshly dissected bones were fixed in 4% paraformaldehyde overnight followed by 3 days of decalcification in 10% EDTA dissolved in PBS. Bones were sectioned using the CryoJane tape-transfer system (Instrumedics). For spleen sections, freshly dissected spleens were fixed in 4% paraformaldehyde for 1 h followed by 1 day incubation in 10% sucrose in PBS. Frozen spleens were sectioned with a cryostat (Leica). For whole mount imaging, spleens were sectioned into ~2 mm pieces. Spleen sections were blocked in PBS with 10% horse serum for 1 h and then stained overnight with chicken-anti-GFP (Aves) and/or rabbit-anti-laminin (Abcam) antibodies. Donkey-anti-chicken Alexa Fluor 488 and/or donkey-anti-rabbit Alexa Fluor 647 were used as secondary antibodies (Invitrogen). Specimens were mounted with anti-fade prolong gold (Invitrogen) and images were acquired with either a Zeiss LSM780 confocal microscope or a Leica SP8 confocal microscope equipped with a resonant scanner. Three-dimensional images were achieved using Bitplane Imaris v.7.7.1 software. Spleens were harvested and fixed for 4 h in 4% PFA at 4 °C. Since the spleen capsule is highly autofluorescent, spleens were sectioned perpendicular to the long axis into 300-μm-thick sections using a Leica VT100S vibrotome. These 300-μm sections were fixed for an additional 2 h in 4% PFA and blocked overnight in staining solution (10% dimethylsulfoxide (DMSO), 0.5% IgePal630 (Sigma) and 5% donkey serum (Jackson Immunoresearch) in PBS). All staining steps were performed in staining solution on a rotator at room temperature. Spleen sections were stained for 3 days in primary antibodies, washed overnight in several changes of PBS then stained for 3 days in secondary antibodies. The stained sections were dehydrated in a methanol dehydration series then incubated for 3 h in 100% methanol with several changes. The methanol was then exchanged with benzyl alcohol:benzyl benzoate 1:2 mix (BABB clearing28). The tissues were incubated in BABB for 3 h to overnight with several exchanges of fresh BABB. Spleen sections were mounted in BABB between two coverslips and sealed with silicone (Premium waterproof silicone II clear; General Electric). We found it necessary to clean the BABB of peroxides (which can accumulate as a result of exposure to air and light) by adding 10 g of activated aluminium oxide (Sigma) to 40 ml of BABB and rotating for at least 1 h, then centrifuging at 2,000 g for 10 min to remove the suspended aluminium oxide particles. Images were acquired using a Zeiss LSM780 confocal microscope with a Zeiss LD LCI Plan-Apo ×25/0.8 multi-immersion objective lens, which has a 570 μm working distance. Images were taken at 512 × 512 pixel resolution with 2 μm Z-steps, pinhole for the internal detector at 47.7 μm. Random spots were inserted into images by generating randomized X, Y, and Z coordinates using the random integer generator at http:// www.random.org. After mouse anaesthesia by ketamine/xylazine, a ventral midline incision was made and the peritoneum was breached. The splenic blood vessels were ligated with an absorbable suture (4-0 vicryl). The splenic vessels were cut distal to the suture and the spleen was removed. The vessels were cauterized and the abdomen was sutured with non-absorbable sutures (3-0 Tevdek III). Buprenorphine was administered every 12 h for 3 days to minimize postoperative pain and mice were maintained with ampicillin-containing water to avoid infection. Complete blood counts were measured one month after the survival surgery. EMH was induced by repeated bleeding over a 2-week period according to a published protocol2. Briefly, 4–6 month-old mice were bled via the tail vein five times, every 3 days, removing approximately 250 μl of blood each time, then the mice were killed for analysis 2 days after the last bleed. Approximately 30,000 CD45−Ter119−VE-cadherin+ splenic endothelial cells were flow cytometrically sorted into 50 μl of 66% trichoracetic acid (TCA) in water. Extracts were incubated on ice for at least 15 min and centrifuged at 16,100 g at 4 °C for 10 min. Precipitates were washed in acetone twice and the dried pellets were solubilized in 9 M urea, 2% Triton X-100, and 1% dithiothreitol (DTT). Samples were separated on 4–12% Bis-Tris polyacrylamide gels (Invitrogen) and transferred to PVDF membrane (Millipore). The blots were incubated with primary antibodies overnight at 4 °C and then with secondary antibodies. Blots were developed with the SuperSignal West Femtochemiluminescence kit (Thermo Scientific). Primary antibodies used: rabbit-anti-SCF (Abcam, 1:1,000) and mouse-anti-actin (Santa Cruz, clone AC-15, 1:20,000). Cells were sorted directly into Trizol (Life Technologies). Total RNA was extracted according to the manufacturer’s instructions. Total RNA was reverse transcribed using SuperScript III Reverse Transcriptase (Life Technologies). Quantitative real-time PCR was performed using SYBR green on a LightCycler 480 (Roche). β-Actin was used to normalize the RNA content of samples. Primers used in this study were Scf: 5′-GCCAGAAACTAGATCCTTTACTCCTGA-3′ and 5′-CATAAATGGTTTTGTGACACTGACTCTG-3′; β-actin: 5′-GCTCTTTTCCAGCCTTCCTT-3′ and 5′-CTTCTGCATCCTGTCAGCAA-3′. Three independent samples of 5,000 spleen Scf-GFP+VE-cadherin− spleen stromal cells and two independent samples of 5,000 unfractionated spleen cells were flow cytometrically sorted into Trizol. Total RNA was extracted, amplified, and sense strand cDNA was generated using the Ovation Pico WTA System V2 (NuGEN) according to the manufacturer’s instructions. cDNA was fragmented and biotinylated using the Encore Biotin Module (NuGEN) according to the manufacturer’s instructions. Labelled cDNA was hybridized to Affymetrix Mouse Gene ST 1.0 chips according to the manufacturer’s instructions. Expression values for all probes were normalized and determined using the robust multi-array average (RMA) method29. Panels in all figures represented multiple independent experiments performed on different days with different mice. Sample sizes were not based on power calculations. No randomization or blinding was performed. No animals were excluded from analysis. Variation is always indicated using standard deviation. For analysis of the statistical significance of differences between two groups we generally performed two-tailed Student’s t-tests. For analysis of the statistical significance of differences among more than two groups, we performed repeated measures one-way analysis of variance (ANOVA) tests with Greenhouse–Geisser correction (variances between groups were not equal) and Tukey’s multiple comparison tests with individual variances computed for each comparison. To assess the statistical significance of differences in fetal mass between paired control and mutant mice (Fig. 5j and Extended Data Fig. 8v), we performed a two-way ANOVA.

Holley T.,Translational Genomics Research Institute | Lenkiewicz E.,Translational Genomics Research Institute | Evers L.,Translational Genomics Research Institute | Tembe W.,Translational Genomics Research Institute | And 16 more authors.
PLoS ONE | Year: 2012

Formalin fixed paraffin embedded (FFPE) tissues are a vast resource of annotated clinical samples. As such, they represent highly desirable and informative materials for the application of high definition genomics for improved patient management and to advance the development of personalized therapeutics. However, a limitation of FFPE tissues is the variable quality of DNA extracted for analyses. Furthermore, admixtures of non-tumor and polyclonal neoplastic cell populations limit the number of biopsies that can be studied and make it difficult to define cancer genomes in patient samples. To exploit these valuable tissues we applied flow cytometry-based methods to isolate pure populations of tumor cell nuclei from FFPE tissues and developed a methodology compatible with oligonucleotide array CGH and whole exome sequencing analyses. These were used to profile a variety of tumors (breast, brain, bladder, ovarian and pancreas) including the genomes and exomes of matching fresh frozen and FFPE pancreatic adenocarcinoma samples. © 2012 Holley et al. Source

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