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Dominguez MH, Chattopadhyay PK, Ma S, Lamoreaux L, McDavid A, Finak G, Gottardo R, Koup RA, Roederer M. Highly multiplexed quantitation of gene expression on single cells. J Immunol Methods 2013; 391:133-45. [PMID: 23500781 DOI: 10.1016/j.jim.2013.03.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/04/2013] [Accepted: 03/04/2013] [Indexed: 01/12/2023]
Abstract
Highly multiplexed, single-cell technologies reveal important heterogeneity within cell populations. Recently, technologies to simultaneously measure expression of 96 (or more) genes from a single cell have been developed for immunologic monitoring. Here, we report a rigorous, optimized, quantitative methodology for using this technology. Specifically: we describe a unique primer/probe qualification method necessary for quantitative results; we show that primers do not compete in highly multiplexed amplifications; we define the limit of detection for this assay as a single mRNA transcript; and, we show that the technical reproducibility of the system is very high. We illustrate two disparate applications of the platform: a "bulk" approach that measures expression patterns from 100 cells at a time in high throughput to define gene signatures, and a single-cell approach to define the coordinate expression patterns of multiple genes and reveal unique subsets of cells.
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Affiliation(s)
- Maria H Dominguez
- ImmunoTechnology Section, Vaccine Research Center, NIAID, NIH, United States
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McDavid A, Finak G, Chattopadyay PK, Dominguez M, Lamoreaux L, Ma SS, Roederer M, Gottardo R. Data exploration, quality control and testing in single-cell qPCR-based gene expression experiments. ACTA ACUST UNITED AC 2012; 29:461-7. [PMID: 23267174 PMCID: PMC3570210 DOI: 10.1093/bioinformatics/bts714] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Motivation: Cell populations are never truly homogeneous; individual cells exist in biochemical states that define functional differences between them. New technology based on microfluidic arrays combined with multiplexed quantitative polymerase chain reactions now enables high-throughput single-cell gene expression measurement, allowing assessment of cellular heterogeneity. However, few analytic tools have been developed specifically for the statistical and analytical challenges of single-cell quantitative polymerase chain reactions data. Results: We present a statistical framework for the exploration, quality control and analysis of single-cell gene expression data from microfluidic arrays. We assess accuracy and within-sample heterogeneity of single-cell expression and develop quality control criteria to filter unreliable cell measurements. We propose a statistical model accounting for the fact that genes at the single-cell level can be on (and a continuous expression measure is recorded) or dichotomously off (and the recorded expression is zero). Based on this model, we derive a combined likelihood ratio test for differential expression that incorporates both the discrete and continuous components. Using an experiment that examines treatment-specific changes in expression, we show that this combined test is more powerful than either the continuous or dichotomous component in isolation, or a t-test on the zero-inflated data. Although developed for measurements from a specific platform (Fluidigm), these tools are generalizable to other multi-parametric measures over large numbers of events. Availability: All results presented here were obtained using the SingleCellAssay R package available on GitHub (http://github.com/RGLab/SingleCellAssay). Contact:rgottard@fhcrc.org Supplementary information:Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Andrew McDavid
- Department of Statistics, University of Washington, Seattle, WA 98195, USA
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Lamoreaux L, Koup RA, Roederer M. OMIP-009: Characterization of antigen-specific human T-cells. Cytometry A 2012; 81:362-3. [DOI: 10.1002/cyto.a.22042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 01/04/2012] [Accepted: 02/26/2012] [Indexed: 11/07/2022]
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Zarkowsky D, Lamoreaux L, Chattopadhyay P, Koup RA, Perfetto SP, Roederer M. Heavy metal contaminants can eliminate quantum dot fluorescence. Cytometry A 2011; 79:84-9. [PMID: 21182185 DOI: 10.1002/cyto.a.20986] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Quantum dots (QD) are fluorescent nanocrystals that are highly useful in imaging and flow cytometric analyses. During routine use of monoclonal antibody conjugates of QD, we have occasionally seen partial or total loss of fluorescence when using certain lots of fixative solutions. We hypothesized that a low level contamination with heavy metal cations was responsible, since low level metal contaminants are not uncommon in formalin solutions. By titrating known concentrations of heavy metal cations into staining solutions, we found that millimolar concentrations of ferrous and zinc ions, and as low as 50 nanomolar cupric ions, completely eliminated QD fluorescence. By mass spectroscopic quantification of metals in commercial fixative solutions previously shown to perform poorly or well with regard to QD fluorescence, we confirmed that the presence of copper in solution was correlated with poor performance. Notably, prior addition of EDTA to chelate the divalent cations in these solutions prevented the inhibition of QD fluorescence. Finally, the copper-induced loss of QD fluorescence is irreversible: cells labeled with QD are highly fluorescent and can be rendered nonfluorescent by the addition of cupric sulfate, even after washing extensively. Indeed, these cells can then be successfully stained with other QD reagents, providing a method for immunofluorescence restaining of cells without contaminating fluorescence from the first stain.
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Affiliation(s)
- David Zarkowsky
- Laboratory of Immunology, Vaccine Research Center, NIAID, NIH, Bethesda, Maryland USA
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Perfetto SP, Chattopadhyay PK, Lamoreaux L, Nguyen R, Ambrozak D, Koup RA, Roederer M. Amine-reactive dyes for dead cell discrimination in fixed samples. ACTA ACUST UNITED AC 2010; Chapter 9:Unit 9.34. [PMID: 20578108 DOI: 10.1002/0471142956.cy0934s53] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Amine-reactive dyes, also known as LIVE/DEAD fixable dead cell stains, are a class of viability dyes suitable for identifying dead cells in samples that will be fixed. These dyes cross the cell membranes of dead cells, and react with free amines in the cytoplasm. Live cells exclude these dyes because their cell membranes are intact, and free dye is washed away after staining. Notably, the reaction is irreversible; therefore, when cells are fixed and permeabilized (as with intracellular staining procedures), the bound dye remains associated with the dead cells (unlike other viability dyes). Since amine-reactive dyes are fluorescent when excited by lasers, dead cells can be identified by flow cytometry. This unit describes procedures, troubleshooting, and outcomes for using the two most commonly used amine-reactive dyes, ViViD and Aqua Blue.
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Freel SA, Chattopadhyay PK, Lamoreaux L, Zarkowsky D, Overman RG, Ochsenbauer-Jambor C, Kappes JC, Cunningham CK, Denny TN, Weinhold KJ, Ferrari G, Koup RA, Graham BS, Haynes BF, Roederer M, Tomaras GD. S01-04 OA. Phenotypic analyses of CD8+ T cells that mediate virus inhibition from HIV-1 vaccinees and HIV-1+ virus controllers. Retrovirology 2009; 6 Suppl 3:O1-52, P1-425. [PMID: 19849813 PMCID: PMC2767529 DOI: 10.1186/1742-4690-6-s3-o1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Daucher M, Price DA, Brenchley JM, Lamoreaux L, Metcalf JA, Rehm C, Nies-Kraske E, Urban E, Yoder C, Rock D, Gumkowski J, Betts MR, Dybul MR, Douek DC. Virological outcome after structured interruption of antiretroviral therapy for human immunodeficiency virus infection is associated with the functional profile of virus-specific CD8+ T cells. J Virol 2008; 82:4102-14. [PMID: 18234797 PMCID: PMC2292997 DOI: 10.1128/jvi.02212-07] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Accepted: 01/19/2008] [Indexed: 12/11/2022] Open
Abstract
A clear understanding of the antiviral effects of CD8(+) T cells in the context of chronic human immunodeficiency virus (HIV) infection is critical for the development of prophylactic vaccines and therapeutics designed to support T-cell-mediated immunity. However, defining the potential correlates of effective CD8(+) T-cell immunity has proven difficult; notably, comprehensive analyses have demonstrated that the size and shape of the CD8(+) T-cell response are not necessarily indicative of efficacy determined by measures of plasma viral load. Here, we conducted a detailed quantitative and qualitative analysis of CD8(+) T-cell responses to autologous virus in a cohort of six HIV-infected individuals with a history of structured interruption of antiretroviral therapy (ART) (SIT). The magnitude and breadth of the HIV-specific response did not, by themselves, explain the changes observed in plasma virus levels after the cessation of ART. Furthermore, mutational escape from targeted epitopes could not account for the differential virological outcomes in this cohort. However, the functionality of HIV-specific CD8(+) T-cell populations upon antigen encounter, determined by the simultaneous and independent measurement of five CD8(+) T-cell functions (degranulation and gamma interferon, macrophage inflammatory protein 1beta, tumor necrosis factor alpha, and interleukin-2 levels) reflected the emergent level of plasma virus, with multiple functions being elicited in those individuals with lower levels of viremia after SIT. These data show that the quality of the HIV-specific CD8(+) T-cell response, rather than the quantity, is associated with the dynamics of viral replication in the absence of ART and suggest that the effects of SIT can be assessed by measuring the functional profile of HIV-specific CD8(+) T cells.
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Affiliation(s)
- Marybeth Daucher
- National Institute of Allergy and Infectious Diseases, Bldg. 10/Rm. 11B13, Bethesda, MD 20892, USA.
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Abstract
We describe here a method for optimizing the use of polychromatic flow cytometry (with up to 17 fluorochromes simultaneously) in surface and intracellular staining of human T lymphocytes. We will highlight and discuss how to procedurally optimize key steps in the experimental process before an intracellular cytokine staining assay protocol is finalized. These include but are not limited to the titration of monoclonal antibodies, use of a dead-cell discriminator and 'dump' channel, selection of a cytokine secretion inhibitor, selection of fixation and permeabilization reagents, and inclusion of compensation controls. Building on this basic protocol, we then establish a polychromatic assay designed to detect five separate functions of T lymphocytes (production of three cytokines and one chemokine, and degranulation) while simultaneously identifying multiple surface markers on the responding cells.
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Affiliation(s)
- Laurie Lamoreaux
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Disease, National Institutes of Health, 40 Convent Drive, Bethesda, Maryland 20892, USA.
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Graham BS, Koup RA, Roederer M, Bailer RT, Enama ME, Moodie Z, Martin JE, McCluskey MM, Chakrabarti BK, Lamoreaux L, Andrews CA, Gomez PL, Mascola JR, Nabel GJ. Phase 1 safety and immunogenicity evaluation of a multiclade HIV-1 DNA candidate vaccine. J Infect Dis 2006; 194:1650-60. [PMID: 17109336 PMCID: PMC2428069 DOI: 10.1086/509259] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Accepted: 06/26/2006] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Gene-based vaccine delivery is an important strategy in the development of a preventive vaccine for acquired immunodeficiency syndrome (AIDS). Vaccine Research Center (VRC) 004 is the first phase 1 dose-escalation study of a multiclade HIV-1 DNA vaccine. METHODS VRC-HIVDNA009-00-VP is a 4-plasmid mixture encoding subtype B Gag-Pol-Nef fusion protein and modified envelope (Env) constructs from subtypes A, B, and C. Fifty healthy, uninfected adults were randomized to receive either placebo (n=10) or study vaccine at 2 mg (n=5), 4 mg (n=20), or 8 mg (n=15) by needle-free intramuscular injection. Humoral responses (measured by enzyme-linked immunosorbant assay, Western blotting, and neutralization assay) and T cell responses (measured by enzyme-linked immunospot assay and intracellular cytokine staining after stimulation with antigen-specific peptide pools) were measured. RESULTS The vaccine was well tolerated and induced cellular and humoral responses. The maximal CD4(+) and CD8(+) T cell responses occurred after 3 injections and were in response to Env peptide pools. The pattern of cytokine expression by vaccine-induced HIV-specific T cells evolved over time, with a diminished frequency of interferon- gamma -producing T cells and an increased frequency of interleukin-2-producing T cells at 1 year. CONCLUSIONS DNA vaccination induced antibody to and T cell responses against 3 major HIV-1 subtypes and will be further evaluated as a potential component of a preventive AIDS vaccine regimen.
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MESH Headings
- AIDS Vaccines/administration & dosage
- AIDS Vaccines/adverse effects
- AIDS Vaccines/immunology
- Adolescent
- Adult
- Antibodies, Viral/blood
- Antibody Specificity
- Blotting, Western
- CD4-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/immunology
- Cytokines/analysis
- Cytokines/biosynthesis
- Double-Blind Method
- Enzyme-Linked Immunosorbent Assay
- Female
- Fusion Proteins, gag-pol/genetics
- Fusion Proteins, gag-pol/immunology
- Gene Products, nef/genetics
- Gene Products, nef/immunology
- Genetic Vectors
- HIV Infections/blood
- HIV Infections/immunology
- HIV-1/immunology
- Humans
- Immunization Schedule
- Injections, Intramuscular
- Male
- Neutralization Tests
- Plasmids
- Vaccination
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/adverse effects
- Vaccines, DNA/immunology
- Viral Envelope Proteins/genetics
- Viral Envelope Proteins/immunology
- nef Gene Products, Human Immunodeficiency Virus
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Affiliation(s)
- Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-3017, USA.
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10
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Perfetto SP, Chattopadhyay PK, Lamoreaux L, Nguyen R, Ambrozak D, Koup RA, Roederer M. Amine reactive dyes: An effective tool to discriminate live and dead cells in polychromatic flow cytometry. J Immunol Methods 2006; 313:199-208. [PMID: 16756987 DOI: 10.1016/j.jim.2006.04.007] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2006] [Accepted: 04/04/2006] [Indexed: 11/19/2022]
Abstract
Membrane-damaged cells caused by either mechanical trauma or through normal biological processes can produce artifacts in immunophenotyping analysis by flow cytometry. Dead cells can nonspecifically bind monoclonal antibody conjugates, potentially leading to erroneous conclusions, particularly when cell frequencies are low. To date, DNA intercalating dyes (Ethidium monoazaide (EMA), Propidium Iodide, 7AAD, etc.) or Annexin V have been commonly used to exclude dead cells; however, each suffer from technical problems. The first issue with such dyes is the dependence on a consistent dead cell source for fluorescence compensation. Another major issue is the stability of the staining; except for EMA, fixation and permeablization used for intracellular staining procedures can cause loss of fluorescence. EMA requires a UV exposure to covalently bond to DNA; while this dye is effective and is not affected by intracellular treatments it is weakly fluorescent. Here we report on the optimization of a new class of viability dyes, the amine reactive viability dyes (ViD) as a dead cell exclusion marker. The inclusion of ViD into the staining panel was found to be simple, reproducible and can have a significant benefit on the accuracy of identifying appropriate cell populations. We show the fluorescence of cells stained with these dyes correlates with traditional dead cell discriminating markers, even after fixation and permeabilization. Amine reactive viability dyes are a powerful tool for fluorescence immunophenotyping experiments.
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Affiliation(s)
- Stephen P Perfetto
- Immunology Laboratory, Vaccine Research Center, NIAID, NIH, 40 Convent Dr, Room 5509, Bethesda, MD 20892, USA
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11
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Sullivan NJ, Geisbert TW, Geisbert JB, Shedlock DJ, Xu L, Lamoreaux L, Custers JHHV, Popernack PM, Yang ZY, Pau MG, Roederer M, Koup RA, Goudsmit J, Jahrling PB, Nabel GJ. Immune protection of nonhuman primates against Ebola virus with single low-dose adenovirus vectors encoding modified GPs. PLoS Med 2006; 3:e177. [PMID: 16683867 PMCID: PMC1459482 DOI: 10.1371/journal.pmed.0030177] [Citation(s) in RCA: 169] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Accepted: 02/14/2006] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Ebola virus causes a hemorrhagic fever syndrome that is associated with high mortality in humans. In the absence of effective therapies for Ebola virus infection, the development of a vaccine becomes an important strategy to contain outbreaks. Immunization with DNA and/or replication-defective adenoviral vectors (rAd) encoding the Ebola glycoprotein (GP) and nucleoprotein (NP) has been previously shown to confer specific protective immunity in nonhuman primates. GP can exert cytopathic effects on transfected cells in vitro, and multiple GP forms have been identified in nature, raising the question of which would be optimal for a human vaccine. METHODS AND FINDINGS To address this question, we have explored the efficacy of mutant GPs from multiple Ebola virus strains with reduced in vitro cytopathicity and analyzed their protective effects in the primate challenge model, with or without NP. Deletion of the GP transmembrane domain eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of magnitude. In contrast, a point mutation was identified that abolished this cytopathicity but retained immunogenicity and conferred immune protection in the absence of NP. The minimal effective rAd dose was established at 10(10) particles, two logs lower than that used previously. CONCLUSIONS Expression of specific GPs alone vectored by rAd are sufficient to confer protection against lethal challenge in a relevant nonhuman primate model. Elimination of NP from the vaccine and dose reductions to 10(10) rAd particles do not diminish protection and simplify the vaccine, providing the basis for selection of a human vaccine candidate.
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Affiliation(s)
- Nancy J Sullivan
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thomas W Geisbert
- 2United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Joan B Geisbert
- 2United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, United States of America
| | - Devon J Shedlock
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ling Xu
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Laurie Lamoreaux
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | | | - Paul M Popernack
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Zhi-Yong Yang
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | | | - Mario Roederer
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Richard A Koup
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | | | - Peter B Jahrling
- 4Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Gary J Nabel
- 1Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail:
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Maecker HT, Rinfret A, D'Souza P, Darden J, Roig E, Landry C, Hayes P, Birungi J, Anzala O, Garcia M, Harari A, Frank I, Baydo R, Baker M, Holbrook J, Ottinger J, Lamoreaux L, Epling CL, Sinclair E, Suni MA, Punt K, Calarota S, El-Bahi S, Alter G, Maila H, Kuta E, Cox J, Gray C, Altfeld M, Nougarede N, Boyer J, Tussey L, Tobery T, Bredt B, Roederer M, Koup R, Maino VC, Weinhold K, Pantaleo G, Gilmour J, Horton H, Sekaly RP. Standardization of cytokine flow cytometry assays. BMC Immunol 2005; 6:13. [PMID: 15978127 PMCID: PMC1184077 DOI: 10.1186/1471-2172-6-13] [Citation(s) in RCA: 183] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2004] [Accepted: 06/24/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cytokine flow cytometry (CFC) or intracellular cytokine staining (ICS) can quantitate antigen-specific T cell responses in settings such as experimental vaccination. Standardization of ICS among laboratories performing vaccine studies would provide a common platform by which to compare the immunogenicity of different vaccine candidates across multiple international organizations conducting clinical trials. As such, a study was carried out among several laboratories involved in HIV clinical trials, to define the inter-lab precision of ICS using various sample types, and using a common protocol for each experiment (see additional files online). RESULTS Three sample types (activated, fixed, and frozen whole blood; fresh whole blood; and cryopreserved PBMC) were shipped to various sites, where ICS assays using cytomegalovirus (CMV) pp65 peptide mix or control antigens were performed in parallel in 96-well plates. For one experiment, antigens and antibody cocktails were lyophilised into 96-well plates to simplify and standardize the assay setup. Results ((CD4+)cytokine+ cells and (CD8+)cytokine+ cells) were determined by each site. Raw data were also sent to a central site for batch analysis with a dynamic gating template. Mean inter-laboratory coefficient of variation (C.V.) ranged from 17-44% depending upon the sample type and analysis method. Cryopreserved peripheral blood mononuclear cells (PBMC) yielded lower inter-lab C.V.'s than whole blood. Centralized analysis (using a dynamic gating template) reduced the inter-lab C.V. by 5-20%, depending upon the experiment. The inter-lab C.V. was lowest (18-24%) for samples with a mean of > 0.5% IFNgamma + T cells, and highest (57-82%) for samples with a mean of < 0.1% IFNgamma + cells. CONCLUSION ICS assays can be performed by multiple laboratories using a common protocol with good inter-laboratory precision, which improves as the frequency of responding cells increases. Cryopreserved PBMC may yield slightly more consistent results than shipped whole blood. Analysis, particularly gating, is a significant source of variability, and can be reduced by centralized analysis and/or use of a standardized dynamic gating template. Use of pre-aliquoted lyophilized reagents for stimulation and staining can provide further standardization to these assays.
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Affiliation(s)
| | - Aline Rinfret
- Université de Montreal and CANVAC, the Canadian Network for Vaccines and Immunotherapeutics, Montreal, Canada
| | - Patricia D'Souza
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Janice Darden
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Eva Roig
- Université de Montreal and CANVAC, the Canadian Network for Vaccines and Immunotherapeutics, Montreal, Canada
| | - Claire Landry
- Université de Montreal and CANVAC, the Canadian Network for Vaccines and Immunotherapeutics, Montreal, Canada
| | - Peter Hayes
- Chelsea and Westminster Hospital and IAVI, London, UK
| | | | - Omu Anzala
- Kenya AIDS Vaccine Initiative (KAVI), University of Nairobi, Kenya
| | - Miguel Garcia
- Centre Hospitalier Universitaire Vaudois and EUROVAC, Lausanne, Switzerland
| | - Alexandre Harari
- Centre Hospitalier Universitaire Vaudois and EUROVAC, Lausanne, Switzerland
| | - Ian Frank
- University of Washington and HVTN, Fred Hutchinson Cancer Research Center, Seattle, USA
| | - Ruth Baydo
- University of Washington and HVTN, Fred Hutchinson Cancer Research Center, Seattle, USA
| | - Megan Baker
- Duke University Medical Center and HVTN, Durham, USA
| | | | | | - Laurie Lamoreaux
- Vaccine Research Center, National Institutes of Health, Bethesda, USA
| | | | | | | | | | | | | | | | - Hazel Maila
- National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Ellen Kuta
- Henry Jackson Foundation, Rockville, USA
| | | | - Clive Gray
- National Institute for Communicable Diseases, Johannesburg, South Africa
| | | | | | - Jean Boyer
- University of Pennsylvania, Philadelphia, USA
| | | | | | - Barry Bredt
- University of California, San Francisco, USA
| | - Mario Roederer
- Vaccine Research Center, National Institutes of Health, Bethesda, USA
| | - Richard Koup
- Vaccine Research Center, National Institutes of Health, Bethesda, USA
| | | | - Kent Weinhold
- Duke University Medical Center and HVTN, Durham, USA
| | - Giuseppe Pantaleo
- Centre Hospitalier Universitaire Vaudois and EUROVAC, Lausanne, Switzerland
| | - Jill Gilmour
- Chelsea and Westminster Hospital and IAVI, London, UK
| | - Helen Horton
- University of Washington and HVTN, Fred Hutchinson Cancer Research Center, Seattle, USA
| | - Rafick P Sekaly
- Université de Montreal and CANVAC, the Canadian Network for Vaccines and Immunotherapeutics, Montreal, Canada
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13
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Havens CG, Bryant N, Asher L, Lamoreaux L, Perfetto S, Brendle JJ, Werbovetz KA. Cellular effects of leishmanial tubulin inhibitors on L. donovani. Mol Biochem Parasitol 2000; 110:223-36. [PMID: 11071278 DOI: 10.1016/s0166-6851(00)00272-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To aid our investigation of tubulin as an antileishmanial drug target, the effects of the mammalian antimicrotubule agents ansamitocin P3, taxol, and hemiasterlin on Leishmania donovani promastigotes were described. These drugs affected the assembly of purified leishmanial tubulin and inhibited the growth of L. donovani promastigotes at micromolar concentrations. When promastigotes were treated with these agents, mitotic partitioning of nuclear DNA and cytokinesis were usually inhibited. The spatial orientation of kinetoplasts was often disturbed, suggesting a role for microtubules in the segregation of these organelles during mitosis. Aberrant cell types produced in drug-treated cultures included parasites with one nucleus and two geometrically distinct kinetoplasts, parasites with multiple kinetoplasts, and cytoplasts containing a kinetoplast but no nucleus. A subset of unique cell types, parasites containing two nuclei, a spindle fiber, and two geometrically distinct kinetoplasts, were observed in hemiasterlin-treated cultures. Flow cytometric analysis of L. donovani promastigotes treated with these three drugs indicated a dramatic shift toward the G2 + M phase of the cell cycle, with some cells containing four times the amount of DNA present in G1. These results were used to evaluate the cellular effects of WR85915, an aromatic thiocyanate with in vitro antileishmanial and anti-tubulin activity, on L. donovani. Treatment of parasites with WR85915 did not produce the unusual cell types described above and did not cause the accumulation of parasites in G2 + M, suggesting that WR85915 acts on target(s) in Leishmania in addition to tubulin. These studies validate tubulin as a suitable antileishmanial drug target and provide criteria to assess the cellular mechanism of action of new candidate antileishmanial agents.
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Affiliation(s)
- C G Havens
- Department of Parasitology, Walter Reed Army Institute of Research, Washington, DC 20307, USA
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Harris NL, Smith DA, Lamoreaux L, Purnell M. Central quadriceps tendon for anterior cruciate ligament reconstruction. Part I: Morphometric and biomechanical evaluation. Am J Sports Med 1997; 25:23-8. [PMID: 9006687 DOI: 10.1177/036354659702500105] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We examined the anatomic and biomechanical adequacy of the central quadriceps tendon as an alternative graft source for anterior cruciate ligament reconstruction. Morphometry was performed on 15 preserved and 6 fresh-frozen specimens. Biomechanical testing was performed on the six fresh-frozen specimens. We initially used a triple suture through the tendon construction, and then clamping directly on the tendon. Morphometry yielded the following measurements: length, 6.1 +/- 1.0 cm; width, 2.7 cm (range, 2.1 to 3.7); and thickness, 7 mm (range, 6.4 to 7.8). The thickness was 1.8 times that of the patellar tendon. Biomechanical testing showed that suture failure occurred at 692 +/- 181 N, and tendon failure occurred at 1075 +/- 449 N. The load to tendon failure was 1.36 times that of a comparable-width patellar tendon graft, although the difference was not statistically significant. The failure mode was primarily through partial or complete tendinous avulsion, with only one specimen failing at midsubstance. These findings show the central quadriceps graft is of sufficient size and strength to be used for anterior cruciate ligament reconstruction.
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Affiliation(s)
- N L Harris
- Department of Orthopaedics, CU Sports Medicine Clinic, University of Colorado Health Sciences Center, Denver 80222, USA
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Dimond KR, Pande AC, Lamoreaux L, Pierce MW. Effect of gabapentin (Neurontin) [corrected] on mood and well-being in patients with epilepsy. Prog Neuropsychopharmacol Biol Psychiatry 1996; 20:407-17. [PMID: 8771597 DOI: 10.1016/0278-5846(96)00005-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
1. Global improvement data from five double-blind clinical trials of gabapentin as add-on therapy in patients with epilepsy were reviewed to assess the effects of gabapentin on mood. 2. One hundred and ninety-four (46%) of 423 gabapentin-treated patients reported improvements in general well-being as compared with 79 (29%) of the 271 placebo-treated patients. 3. Findings support anecdotal reports of improved affective status among patients taking gabapentin and suggest that the study of gabapentin in psychiatric populations may be warranted.
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Affiliation(s)
- K R Dimond
- CNS Clinical Research and Development, Parke-Davis Pharmaceutical Research, Division of Warner-Lambert Company, Ann Arbor, MI, USA
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Lamoreaux L, Hoffer MM. The effect of wrist deviation on grip and pinch strength. Clin Orthop Relat Res 1995:152-5. [PMID: 7634628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effect of wrist deviation on grip and pinch strength was evaluated in 12 normal right-handed adults. Wrist positions of neutral, maximal ulnar (average, 41 degrees), and maximal radial deviation (average, 26 degrees) were held in short-arm casts while grip and key and tip pinch were measured. Wrist position was neutral with respect to flexion and extension. A highly significant effect of wrist deviation on grip strength was found (p < 0.0001). The effect on pinch strength was not statistically significant. Wrist deviation deformities arise in several clinical situations, such as radial clubhand and malunions of the distal radius. A loss of grip strength was found in radial deviation in this study. This would support 1 of the premises for surgical correction of such deviation by centralization or osteotomy.
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Affiliation(s)
- L Lamoreaux
- Rancho Los Amigos Medical Center, Downey, CA, USA
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