Lipid analysis by multiple "omic" mass spectrometry platforms Where we ve been, where we are, and where we re going

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1 Lipid analysis by multiple "omic" mass spectrometry platforms Where we ve been, where we are, and where we re going Jeff McDonald Department of Molecular Genetics UT Southwestern Medical Center Dallas, TX LIPID MAPS Glue Grant NIH U54 GM 69338

2 Lipidome of Human Plasma 588

3 Lipids in Human Serum pg/ml Wikipedia : Reference ranges for blood tests - by mass.svg mg/ml Total cholesterol ~ 2 mg/ml > 6 orders of magnitude Trace oxysterols < 2 ng/ml Triglycerides ~ 1 mg/ml Phospholipids ~ 2 mg/ml Sphingolipids ~ 0.5 mg/ml mg/ml Cholesterol Cholesteryl ester

4 General Steps of Lipid Extraction and Purification 1) Solvent extraction (DCM/MeOH) 2) Base hydrolysis 200μL serum + standards KOH, 60 C Organic-soluble (lipids) Insoluble material/ proteins 4) Solid phase extraction Condition With Load sample hexane in hexane Hexane rinse 23:1 CHCl 3 :MeOH 3) Liquid-Liquid Extraction 5) LC-MS Aqueous (MeOH/H 2 O) Organic (lipids) (DCM/MeOH) Non polar lipids Sterols + oxysterols

5 Analytical Separation and Detection of Lipids HPLC Normal Phase Reverse Phase HELIC Mass Spectrometry Triple Quadrupole (MRM) Neutral Loss Scan Precursor Ion Scan GC DB5-MS 40m 0.18mm i.d. o H 2 carrier gas DB5-MS 30m 0.25 o He Carrier gas Mass Spectrometry Electron Ionization Electron-Capture Negative Ionization o Methane

6 Measurement of the Plasma Lipidome Neutral Lipids 3 Samples 2 Extractions 1 LC, 3 MS Analysis Sterols/Oxysterol 4 Samples 4 Extractions 2 LC-MS Analysis 2 GC-MS Analysis Prenols/Cardiolipins 3 Samples 1 Extraction 3 LC-MS Analysis Phospholipids 2 Samples 2 Extractions 2 LC-MS Analysis Human Plasma Lipidome Fatty Acids/ Eicosanoids 2 Samples 2 Extractions 1 LC-MS Analysis 1 GC-MS Analysis Sphingolipids 1 Sample 3 Extractions 5 LC-MS Analysis Summary 15 Samples 14 Extractions 14 LC-MS methods 3 GC-MS methods 100 s standards 7 Expert Centers $ Millions/many hours

7 The Workhorses of Lipid Analysis AB Sciex Triple Quadrupole Mass Spectrometers Agilent GC-MS

8 Analytical Standards Generated by Avanti Polar Lipids >650 analytical lipid standards 300 new lipid standards Primary, deuterated, odd-chain Purity and stability Packaging, storage, shelf-life In-house analytical expertise

9 Eicosanoids and Fatty Acids from Cayman Chemical 100+ eicosanoid

10 MS-Based Methods Developed by LM Cores lipidmaps.org

11 A Ten-Year Timeline of Lipidomics LIPID MAPS pioneers and advances speciated, quantitative LC/GC-MS methods for lipids Shotgun Lipidomics introduced and implemented by Hann and Gross Broad-scale, targeted and untargeted LC-MS Omics approaches flourish Suizdak, Fiehn, Sumner, Newgard, Roddy, etc Advanced, infusion-based lipidomic methods introduced

12 One Sample, Many Choices Sterols Sphingolipids Phospholipids Neutral Lipids Prenols Eicosanoids/Fatty Acids

13 One Sample, Many Choices Ursus Analyticus Thanks Avanti!

14 Infusion-Based MS Platform for Lipidomic Analysis 1) Sample Extraction (CH 2 Cl 2 /MeOH) 20uL human plasma Small molecule metabolome Insoluble material/ proteins LEAP Robotic Infusion System AB SCIEX TripleTOF MS with SelexION

15 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis

16 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis Plasma+Stds Aqueous Organic (lipids)

17 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis

18 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis CE TOF Scan Da 30-40K resolution < 2ppm mass accuracy PC Cholesterol PE SM TG DG

19 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis m/z 666 CE 18:2

20 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis m/z 369 Product-ion m/z 666 m/z 666 CE 18:2 Neutral Loss 379 = FA 18:2 m/z 666

21 Workflow for Infusion-Based Global Lipidomics B/D Extraction of plasma Infuse into MS Acquire TOF Acquire MS/MS ALL Data Analysis 30 minutes 5 minutes Hour Time Scale

22 Mining the Dataset Post-Acquisition MS/MS ALL identifies 800+ MS features Lipids that contain a 18:1 fatty acid (NL 281Da) Cholesteryl ester C18:1 Triacylglycerol with FA 18:1 Lipids that contain a PC head group (Prec 184 Da) Lyso Phosphatidylcholines Phosphatidylcholine Lipids that contain a PE head group (NL 141 Da) Lyso Phosphatidylethanolamine Phosphatidylethanolamine

23 PCA Analysis MS/MS ALL Data Liver Plasma Blank MarkerView (AB Sciex)

24 Can Infusion-Based Metabolomics be Quantitative? TAG 54:3 LPC 18:0 C 36:2 DAG

25 The Future of Lipidomics Chromatograhic-based quantitative analysis HPLC resolving power and efficiency MS sensitivity MS acquisition speed Flexible, parallel acquisition Infusion-based analysis Resolution, mass accuracy, linearity Data analysis software Off-line HPLC followed by infusion-based MS Ion-mobility Accessibility to standards Class-specific mixtures (primary and internal)

26 Acknolwedgements LIPID MAPS community Phil Sanders Eli Lilly Brigitte Simons AB Sciex Jennifer Krone Mark Cafazzo Lyle Burton AB-Sciex Academic Partnership Program