Home

Applications

APPLICATIONS OVERVIEW
DRUG DISCOVERY
ADME-Tox
Biochemical Assays
Cell-based Assays
HTS and Secondary Screening
Microsampling
Protein Crystallography
RNAi
Sample Management
CANCER RESEARCH
Personalized Medicine
Functional Screening / DSRT
RNAi
Sequencing
Single-cell Genomics
GENOMIC RESEARCH
Gene Expression
Genotyping
Microbiome
qPCR
Sequencing
Single-cell Genomics
Synthetic Biology

Products

LIQUID HANDLING
LIQUID HANDLERS OVERVIEW
Echo® 525 Liquid Handler
Echo® 555 Liquid Handler
Echo® 550 Liquid Handler
Echo® 520 Liquid Handler
AUTOMATION
AUTOMATION OVERVIEW
Access™ Laboratory Workstation
Tempo™ Automation Control Software
SOFTWARE APPLICATIONS
SOFTWARE OVERVIEW
Echo® Array Maker
Echo® Cherry Pick
Echo® Combination Screen
Echo® Compliance Manager
Echo® Dose-Response
Echo® Plate Audit
Echo® Plate Reformat
CONSUMABLES
CONSUMABLES OVERVIEW
Echo® Qualified Microplates
Labcyte® Assay Microplates
MicroClime® Environmental Lid
Echo® Qualified Reservoir

Technology

Echo® Acoustic Liquid Handling
Dynamic Fluid Analysis™
Acoustic Mass Spectrometry
Direct Dilution

News / Events

Labcyte BLOG
Upcoming Events
Press Releases
Labcyte in the News
Labcyte Community

Resources

JALA Special Issue
Publications
Articles and Other Media
Application Notes
Posters
Webinars
Videos
Customer Profiles
Core Labs

Support

Brochures
Web Documentation*
User Guides*
Quick Start Guides*
Specification Sheets
Site Prep Guides
Service and Maintenance
Request Information

Company

About Us
Echo® Acoustic Technology
Leadership Team
Meet Labcyte
Careers
Contact and Location
Privacy Policy

featuring the Echo® Acoustic Technology
PUBLICATIONS

by scientists and researchers like you

103 Total Publications
HOME | RESOURCES | Publications

PUBLICATIONS

103 Total Publications

REFINE YOUR SEARCH



TITLES and AUTHORS Year Link PDF + Abstract
  • Identification and Characterization of Novel Human Glucose-6-Phosphate Dehydrogenase Inhibitors Preuss J, Richardson A D, Pinkerton A, Hedrick M, Sergienko E, Rahlfs S, Becker K, Bode L

    Institution: University of California, Sanford-Burnham Medical Research Institute, Justus Liebig University

    Publication: Journal of Biomedical Screening, September 2012

    2013 abstract

    Glucose-6-phosphate dehydrogenase (G6PD) is the key enzyme of the pentose phosphate pathway, converting glucose-6-phosphate to 6-phosphoglucono-δ-lactone with parallel reduction of NADP+. Several human diseases, including cancer, are associated with increased G6PD activity. To date, only a few G6PD inhibitors have been available. However, adverse side effects and high IC50 values hamper their use as therapeutics and basic research probes. In this study, we developed a high-throughput screening assay to identify novel human G6PD (hG6PD) inhibitors. Screening the LOPAC (Sigma-Aldrich; 1280 compounds), Spectrum (Microsource Discovery System; 1969 compounds), and DIVERSet (ChemBridge; 49 971 compounds) small-molecule compound collections revealed 139 compounds that presented ≥50% hG6PD inhibition. Hit compounds were further included in a secondary and orthogonal assay in order to identify false-positives and to determine IC50 values. The most potent hG6PD inhibitors presented IC50 values of <4 µM. Compared with the known hG6PD inhibitors dehydroepiandrosterone and 6-aminonicotinamide, the inhibitors identified in this study were 100- to 1000-fold more potent and showed different mechanisms of enzyme inhibition. One of the newly identified hG6PD inhibitors reduced viability of the mammary carcinoma cell line MCF10-AT1 (IC50 ~25 µM) more strongly than that of normal MCF10-A cells (IC50 >50 µM).

    Publication / Type:
    Journal of Biomedical Screening, September 2012
    Related Subject:
    Novel Human Glucose-6-Phosphate Dehydrogenase Inhibitors
    Link:
    http://jbx.sagepub.com/content/18/3/286
  • Analysis of Compound Weighing Precision in Drug Discovery Popa-Burke I, Novick S, Mantilla M, McGrath K

    Institution: GlaxoSmithKline, North Carolina State University

    Publication: Journal of Biomedical Screening, September 2012

    2013 abstract

    Early drug discovery laboratories often call for the precise weighing of 1- to 5-mg solids into 4- to 5-g glass vials. For the balance used in this study (Mettler Toledo XP205), the manufacturer rates its accuracy at ±0.01 mg over the working range of 1 mg to 220 g and its precision or repeatability at 0.015 mg for 10-g weights. The manufacturer ratings were confirmed using standard steel weights, but these calibrators do not well represent the weighing precision of drug compound. For example, when pre-taring a 4- to 5-g vial on the balance and then weighing 1- to 5-mg calibration weights, although no bias was observed, precision dropped appreciably. When measuring solid sample in the range of 1 to 5 mg, deviation of the measured weight from the actual (true) weight was even worse, in the range of ±20% to 50%. Balance settings and environmental factors exert a strong influence on weighing precision. Although most environmental factors, such as air draughts, temperature, vibrations, and levelness, can be optimized to the extent practical in laboratory settings, problems due to static electricity are often overlooked. By controlling static electricity, we demonstrate how we optimized the process to where measurements were within ±10% of actual weight when weighing solid sample in the range of 2 to 5 mg and ±20% when weighing 1 mg into a 4- to 5-g vial. Our weighing process and method to calculate actual weight are given in detail.

    Publication / Type:
    Journal of Biomedical Screening, September 2012
    Related Subject:
    Compound Weighing Precision Drug Discovery
    Link:
    http://jbx.sagepub.com/content/18/3/331
  • High-Precision, Room Temperature Screening Assay for Inhibitors of Microsomal Prostaglandin E Synthase-I Anderson S, Norman M, Olsson R, Smith R, Liu G, Nord J

    Institution: AstraZeneca

    Publication: Journal of Biomolecular Screening 17(10) 1372–1378 © 2012 SLAS

    2012 abstract

    Microsomal prostaglandin E synthase-1 (mPGES-1) is the major enzyme catalyzing the isomerization of prostaglandin (PG) H2 to PGE2. Here we report the development of a robust and practical automated assay in a 384-well format for room temperature screening of mPGES-1 inhibitors with high precision and low reagent consumption. The assay should enable precise structure-activity relationship development. It uses acetonitrile as solvent for PGH2, FeCl2/citrate as stop reagent, and a short reaction time. Combined with high-precision liquid transfer and extensive mixing after addition of reactants, these properties let the assay reach Z' > 0.7 and high reproducibility of inhibitor IC50 values. Thorough investigation of the quality of mixing in all liquid transfer steps proved crucial for reaching high-precision performance.

    Publication / Type:
    Journal of Biomolecular Screening 17(10) 1372–1378 © 2012 SLAS
    Related Subject:
    automation or robotics, liquid handling, enzyme assays or enzyme kinetics, fluorescence methods, inflammation, autoimmune diseases, Room Temperature Microsomal Prostaglandin E Synthase-I
    Link:
    http://jbx.sagepub.com/content/17/10/1372
  • 3D Imaging by Mass Spectrometry: A New Frontier Seeley E H, Caprioli R M

    Institution: Vanderbilt University

    Publication: Anal Chem. 2012 Mar 6;84(5):2105-10. doi: 10.1021/ac2032707

    2012 abstract

    Imaging mass spectrometry can generate three-dimensional volumes showing molecular distributions in an entire organ or animal through registration and stacking of serial tissue sections. Here, we review the current state of 3D imaging mass spectrometry as well as provide insights and perspectives on the process of generating 3D mass spectral data along with a discussion of the process necessary to generate a 3D image volume.

    Publication / Type:
    Anal Chem. 2012 Mar 6;84(5):2105-10. doi: 10.1021/ac2032707
    Related Subject:
    3D Imaging Mass Spectrometry
    Link:
    http://pubs.acs.org/doi/pdf/10.1021/ac2032707
  • Dual Analysis for Mycobacteria and Propionibacteria in Sarcoidosis BAL Oswald-Richter K A, Beachboard D C, Seeley E H, Abraham S, Shepherd B E, Jenkins C A, Culver D A, Ca

    Institution: Vanderbilt University

    Publication: J Clin Immunol. 2012 October; 32(5): 1129–1140.  doi:  10.1007/s10875-012-9700-5

    2012 abstract

    Purpose
    Sarcoidosis is a non-caseating granulomatous disease for which a role for infectious antigens continues to strengthen. Recent studies have reported molecular evidence of mycobacteria or propionibacteria. We assessed for immune responses against mycobacterial and propionibacterial antigens in sarcoidosis bronchoalveolar lavage (BAL) using flow cytometry, and localized signals consistent with microbial antigens with sarcoidosis specimens, using matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS).

    Methods
    BAL cells from 27 sarcoidosis, 14 PPD- controls, and 9 subjects with nontuberculosis mycobacterial (NTM) infections were analyzed for production of IFN-γ after stimulation with mycobacterial ESAT-6 and Propionibacterium acnes proteins. To complement the immunological data, MALDI-IMS was performed to localize ESAT-6 and Propionibacterium acnes signals within sarcoidosis and control specimens.

    Results
    CD4+ immunologic analysis for mycobacteria was positive in 17/27 sarcoidosis subjects, compared to 2/14 PPD- subjects, and 5/9 NTM subjects (p = 0.008 and p = 0.71 respectively, Fisher’s exact test). There was no significant difference for recognition of P. acnes, which occurred only in sarcoidosis subjects that also recognized ESAT-6. Similar results were also observed for the CD8+ immunologic analysis. MALDI-IMS localized signals consistent with ESAT-6 only within sites of granulomatous inflammation, whereas P. acnes signals were distributed throughout the specimen.

    Conclusions
    MALDI-IMS localizes signals consistent with ESAT-6 to sarcoidosis granulomas, whereas no specific localization of P. acnes signals is detected. Immune responses against both mycobacterial and P. acnes are present within sarcoidosis BAL, but only mycobacterial signals are distinct from disease controls. These immunologic and molecular investigations support further investigation of the microbial community within sarcoidosis granulomas.

    Publication / Type:
    J Clin Immunol. 2012 October; 32(5): 1129–1140.  doi:  10.1007/s10875-012-9700-5
    Related Subject:
    Mycobacteria Propionibacteria Sarcoidosis BAL
    Link:
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3526106/
  • A Cell-Based High-Throughput Screening Assay to Measure Cellular Histone H3 Lys27 Trimethylation with a Modified Dissociation-Enhanced Lanthanide Fluorescent Immunoassay Xie W, Ames R S, Li H

    Institution: GlaxoSmithKline

    Publication: J Biomol Screen January 2012 vol. 17 no. 1 99-107

    2012 abstract

    Histone proteins are subject to several modifications, including phosphorylation, acetylation, methylation, sumoylation, and ubiquitination. These posttranslational modifications play critical roles in chromatin structure and gene transcription. Because of their involvement in the progression of a variety of diseases, histone modifications are attracting increased attention. We report herein a high-throughput DELFIA assay to quantify H3K27me3 in the prostate cancer cell line, PC3. Using a high binding MaxiSorp plate, we were able to eliminate the need for the capture antibody. We also developed an effective method, a combination of “freeze-thaw” and 0.2 N HCl, to extract histone proteins in PC3 cells cultured in a 384-well plate. To compensate for cell viability change, we normalized H3K27me3 signal to the total amount of H3 in each sample well. As a result, we show that the assay has a good dynamic range with a robust assay window. Using a methlytransferase inhibitor, DZNep, we show that the change of H3K27me3 signal is target specific. This method simplifies the logistics in screening and profiling and reduces the cost per well to an acceptable level for high-throughput screening. The findings presented here should be applicable to other assays involving binding and extraction of histone proteins.

    Publication / Type:
    J Biomol Screen January 2012 vol. 17 no. 1 99-107
    Related Subject:
    Cellular Histone H3 Lys27 Trimethylation Modified Dissociation-Enhanced Lanthanide Fluorescent Immunoassay
    Link:
    http://jbx.sagepub.com/content/17/1/99.abstract
  • Enabling Lead Discovery for Histone Lysine Demethylases by High-Throughput RapidFire Mass Spectrometry Hutchinson S E, Leveridge M V, Heathcote M L, Francis P, Williams L, Gee M, Munoz-Muriedas J, Leaven

    Institution: GlaxoSmithKline

    Publication: J Biomol Screen January 2012 vol. 17 no. 1 39-48

    2012 abstract

    A high-throughput RapidFire mass spectrometry assay is described for the JMJD2 family of Fe2+, O2, and α-ketoglutarate-dependent histone lysine demethylases. The assay employs a short amino acid peptide substrate, corresponding to the first 15 amino acid residues of histone H3, but mutated at two positions to increase assay sensitivity. The assay monitors the direct formation of the dimethylated-Lys9 product from the trimethylated-Lys9 peptide substrate. Monitoring the formation of the monomethylated and des-methylated peptide products is also possible. The assay was validated using known inhibitors of the histone lysine demethylases, including 2,4-pyridinedicarboxylic acid and an α-ketoglutarate analogue. With a sampling rate of 7 s per well, the RapidFire technology permitted the single-concentration screening of 101 226 compounds against JMJD2C in 10 days using two instruments, typically giving Z′ values of 0.75 to 0.85. Several compounds were identified of the 8-hydroxyquinoline chemotype, a known series of inhibitors of the Lys9-specific histone demethylases. The peptide also functions as a substrate for JMJD2A, JMJD2D, and JMJD2E, thus enabling the development of assays for all 3 enzymes to monitor progress in compound selectivity. The assay represents the first report of a RapidFire mass spectrometry assay for an epigenetics target.

    Publication / Type:
    J Biomol Screen January 2012 vol. 17 no. 1 39-48
    Related Subject:
    Histone Lysine Demethylases High-Throughput RapidFire Mass Spectrometry
    Link:
    http://jbx.sagepub.com/content/17/1/39.abstract
  • Design of an Automated Enhanced-Throughput Platform for Functional Characterization of Positive Allosteric Modulator-Induced Leftward Shifts in Apparent Agonist Potency In Vitro Hendricson A, Matchett M, Ferrante M, Ferrante C, Hunnicutt E, Westphal R, Kostich W, Huang Y, Masia

    Institution: Bristol-Myers Squibb Company

    Publication: Journal of Laboratory Automation April 2012 vol. 17 no. 2 104-115

    2012 abstract

    Prosecution of positive allosteric modulator (PAM) targets demands a specialized assay toolset. Many GPCR or ion channel targets are adaptable to functional assays whereby PAM efficacy can be inferred from left or rightward shifts in the concentration-response curves of orthosteric agonist. The inherent emphasis on throughput and occasional paucity of radioligands for a diverse array of allosteric modulator targets yields a need for an enhanced throughput agonist potency shift assay. Here, we describe a process by which such an assay was automated with robust, reproducible in vitro pharmacology. In direct comparison with a manual CRC shift assay, the enhanced throughput automated platform described here delivered near identical rank orders (r2 = 0.75) at ~4-fold throughput/assay iteration. Correspondingly, average cycle time/plate decreased from 104 to 72 minutes. We also observed reductions in assay interference associated with compounds exhibiting ago-allosterism, which we attribute to preread compound incubation periods which are more precisely time-constrained under automation control. By leveraging automated laboratory technology, we have achieved meaningful throughput with no sacrifice of precision. Rather than to be target-class specific, the present process was specifically designed to serve as a platform template for a variety of cell-based functional allosteric modulation assays.

    Publication / Type:
    Journal of Laboratory Automation April 2012 vol. 17 no. 2 104-115
    Related Subject:
    Allosteric Agonist Potency In Vitro
    Link:
    http://jla.sagepub.com/content/17/2/104.abstract
  • Resorufin Butyrate as a Soluble and Monomeric High-Throughput Substrate for a Triglyceride Lipase Lam V, Henault M, Khougaz K, Fortin L-J, Ouellet M, Melnyk R, Partridge A

    Institution: Merck Frosst Centre for Therapeutic Research

    Publication: J Biomol Screen February 2012 vol. 17 no. 2 245-251

    2012 abstract

    Triglyceride lipases such as lipoprotein lipase, endothelial lipase, and hepatic lipase play key roles in controlling the levels of plasma lipoprotein. Accordingly, small-molecule modulation of these species could alter patient lipid profiles with corresponding health effects. Screening of these enzymes for small-molecule therapeutics has historically involved the use of lipid-based particles to mimic native substrates. However, particle-based artifacts can complicate the discovery of therapeutic molecules. As a simplifying solution, the authors sought to develop an approach involving a soluble and monomeric lipase substrate. Using purified bovine lipoprotein lipase as a model system, they show that the hydrolysis of resorufin butyrate can be fluorescently monitored to give a robust assay (Z′ > 0.8). Critically, using parallel approaches, they show that resorufin butyrate is soluble and monomeric under assay conditions. The presented assay should be useful as a simple and inexpensive primary or secondary screen for the discovery of therapeutic lipase modulators.

    Publication / Type:
    J Biomol Screen February 2012 vol. 17 no. 2 245-251
    Related Subject:
    Resorufin Butyrate Monomeric High-Throughput Substrate Triglyceride Lipase
    Link:
    http://jbx.sagepub.com/content/17/2/245.abstract
  • Case Studies of Minimizing Nonspecific Inhibitors in HTS Campaigns That Use Assay-Ready Plates Liu Y, Beresini M H, Johnson A, Mintzer R, Shah K, Clark K, Schmidt S, Lewis C, Liimatta M, Elliott

    Institution: Genentech, Inc.

    Publication: J Biomol Screen February 2012 vol. 17 no. 2 225-236

    2012 abstract

    Identifying chemical lead matter by high-throughput screening (HTS) has been a common practice in early stage drug discovery. Evolution of small-molecule library composition to include more drug-like molecules with desirable physical chemical properties combined with improving assay technologies has vastly enhanced the capability of HTS. However, HTS campaigns can still be plagued by false positives arising from nonspecific inhibitors. The generation of assay-ready plates has permitted an incremental advancement to the speed and efficiency of HTS but has the potential to enhance the occurrence of nonspecific inhibitors. A subtle change in the order of reagent addition to the assay-ready plates can greatly alleviate false-positive inhibition. Our case studies with six different kinase and protease targets reveal that this type of inhibition affects targets regardless of enzyme class and is unpredictable based on protein construct or inhibitor chemical scaffold. These case studies support a model where a diversity set of compounds should be tested first for hit rates as a function of order of addition, carrier protein, and relevant mechanistic studies prior to launch of the HTS campaign.

    Publication / Type:
    J Biomol Screen February 2012 vol. 17 no. 2 225-236
    Related Subject:
    Nonspecific Inhibitors HTS Assay-Ready Plates
    Link:
    http://jbx.sagepub.com/content/17/2/225.abstract
EXPAND ABSTRACTS




Featured Labcyte Downloads
For Research Use Only Not for use in Diagnostics
TOP