Jeffrey S Forrester

Publications (5)87.89 Total impact

• Article: Quantification of diacylglycerol species from cellular extracts by electrospray ionization mass spectrometry using a linear regression algorithm.

  Hannah L Callender, Jeffrey S Forrester, Pavlina Ivanova, Anita Preininger, Stephen Milne, H Alex Brown
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  ABSTRACT: Diacylglycerols (DAGs) play significant roles in both intermediate metabolism and signal transduction. These lipid species are second messengers involved in modulating a plethora of cellular processes. Evaluation of DAG species concentrations has been hampered by the lack of a reliable method for molecular species analysis within a complex mixture of cellular lipids. We describe a new method for quantitative analysis of DAG species from complex biological extracts based on positive mode electrospray ionization mass spectrometry without prior derivatization. Quantification is achieved using internal standards and calibration curves constructed by spiking cell extracts with different concentrations of DAG species containing various acyl chain lengths and degrees of unsaturation. The new mass spectral data processing algorithm incorporates a multiple linear regression model including a factor accountable for possible interactions between experimental preparations and the slope of the curve for the standards, allowing the examinations of the effects of sample origin conditions (such as cell types, phenotypes, etc.) and instrument variability on this slope. Internal standards provide a basis for quantification of 28 DAG molecular species detected in RAW 264.7 cells after stimulation of a G-protein coupled receptor with platelet activating factor. This method displays excellent reproducibility over the established range of concentrations with variations of < or =10% and is highly sensitive with a detection limit of 0.1-0.4 pmol/microL depending upon acyl chain composition. We have shown differential effects on various DAGs in response to a ligand which illustrates the importance of examining lipids at the molecular species level rather than as a single homogeneous entity.
  Analytical Chemistry 01/2007; 79(1):263-72. · 5.86 Impact Factor
• Article: LIPID arrays: new tools in the understanding of membrane dynamics and lipid signaling.

  Pavlina T Ivanova, Stephen B Milne, Jeffrey S Forrester, H Alex Brown
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  ABSTRACT: Phospholipids are the structural building blocks of the membrane bilayer, which retains and regulates intra-cellular content. In addition to creating a protective barrier around the cell, lipids modulate membrane trafficking and are themselves precursors of important intracellular signaling molecules. Identification and quantification of these molecular species is essential for a more complete understanding of cell signaling pathways, and more reliable and sensitive methods are needed for determining membrane phospholipid content. Recent improvements in electrospray ionization mass spectrometry have made possible the direct identification of more than 400 phospholipid species from biological extracts of a single cell type. Changes in the cellular concentration of diverse lipids can be determined by analysis of the mass spectra by statistical algorithms. In the future, lipid arrays will be integrated with other high-throughput profiling technologies, and computational lipidomics will expand our understanding of the molecular basis of cellular processes and diseases.
  Molecular Interventions 05/2004; 4(2):86-96. · 4.59 Impact Factor
• Article: Computational lipidomics: a multiplexed analysis of dynamic changes in membrane lipid composition during signal transduction.

  Jeffrey S Forrester, Stephen B Milne, Pavlina T Ivanova, H Alex Brown
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  ABSTRACT: Recent successes in defining the roles of lipids in cell signaling have stimulated greater interest in these versatile biomolecules. Until recently, analysis of these molecules at the species level has required labor-intensive techniques. The development of electrospray ionization mass spectrometry (ESI-MS) has made possible the detection and identification of thermally labile biological molecules, such as phospholipids. The "soft" ionization does not cause extensive fragmentation, is highly sensitive, accurate, and reproducible. Thus, this method is well suited for analyzing a broad range of phospholipids without elaborate chromatographic separation. Evaluating the vast amounts of data resulting from these measurements is a rate-limiting step in the assessment of phospholipid composition, requiring the development and application of computational algorithms for mass spectrometry data. Here we describe computational lipidomics, a novel analytical technique, coupling mass spectrometry with statistical algorithms to facilitate the comprehensive analysis of hundreds of lipid species from cellular extracts. As a result, lipid arrays are generated to indicate qualitative changes that occur in lipid composition between experimental or disease states, similar to proteomic and genomic analyses. This review presents a methodological strategy for using ESI-MS combined with a high-power computational analysis to profile time-dependent changes in cellular phospholipids after the addition of an agonist or to evaluate changes promoted by pathophysiological processes. As an illustration, we describe the methods and approaches used to generate lipid arrays for The Alliance for Cellular Signaling (AfCS). These arrays are contributing to a more complete understanding of the participants of cellular signaling pathways after activation of cell surface receptors.
  Molecular Pharmacology 05/2004; 65(4):813-21. · 4.88 Impact Factor
• Source

  Available from: Robert S Sinkovits

  Article: Overview of the Alliance for Cellular Signaling.

  Alfred G Gilman, Melvin I Simon, Henry R Bourne, Bruce A Harris, Rochelle Long, Elliott M Ross, James T Stull, Ronald Taussig, Adam P Arkin, Melanie H Cobb, [......], T Kendall Harden, John Doyle, Martha L Gray, Stephen Michnick, Martin A Schmidt, Mehmet Toner, Roger Y Tsien, Madhusudan Natarajan, Rama Ranganathan, Gilberto R Sambrano
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  ABSTRACT: The Alliance for Cellular Signaling is a large-scale collaboration designed to answer global questions about signalling networks. Pathways will be studied intensively in two cells--B lymphocytes (the cells of the immune system) and cardiac myocytes--to facilitate quantitative modelling. One goal is to catalyse complementary research in individual laboratories; to facilitate this, all alliance data are freely available for use by the entire research community.
  Nature 01/2003; 420(6916):703-6. · 36.28 Impact Factor
• Article: introductionOverview of the Alliance for Cellular Signaling

  Alfred G. Gilman, Melvin I. Simon, Henry R. Bourne, Bruce A. Harris, Rochelle Long, Elliott M. Ross, James T. Stull, Ronald Taussig, Adam P. Arkin, Melanie H. Cobb, [......], T. Kendall Harden, John Doyle, Martha L. Gray, Stephen Michnick, Martin A. Schmidt, Mehmet Toner, Roger Y. Tsien, Madhusudan Natarajan, Rama Ranganathan, Gilberto R. Sambrano
  [show abstract] [hide abstract]
  ABSTRACT: The Alliance for Cellular Signaling is a large-scale collaboration designed to answer global questions about signalling networks. Pathways will be studied intensively in two cells — B lymphocytes (the cells of the immune system) and cardiac myocytes — to facilitate quantitative modelling. One goal is to catalyse complementary research in individual laboratories; to facilitate this, all alliance data are freely available for use by the entire research community.
  Nature 12/2002; 420(6916):703-706. · 36.28 Impact Factor