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Abstract

Introduction

Protocol

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Materials

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Chemistry

HPLC-based Assay to Monitor Extracellular Nucleotide/Nucleoside Metabolism in Human Chronic Lymphocytic Leukemia Cells

Published: July 20th, 2016

DOI:

10.3791/54124

1Department of Medical Sciences, Human Genetics Foundation (HuGeF), University of Turin

The protocol described here represents an easy and reproducible method that employs reverse phase high-performance liquid chromatography (RP-HPLC) to measure purine metabolism on chronic lymphocytic leukemia (CLL) cells cultured under different conditions.

This method describes a sensitive, specific, reliable and reproducible reverse phase high-performance liquid chromatography (RP-HPLC) assay developed and validated for the quantification of extracellular purine nucleotides and nucleosides produced by purified chronic lymphocytic leukemia (CLL) cells under different culture conditions. The chromatographic separation of adenosine 5'-monophosphate (AMP), adenosine (ADO) and inosine (INO) is performed at RT on a silica-based, reversed-phase column that is used for polar compound retention. The method includes a binary mobile phase, which consists of 7 mM ammonium acetate and acetonitrile with a flow rate of 1.00 ml/min. The eluates are monitored using a Photodiode Array UV detector set at 260 nm. A standard calibration curve is generated to calculate the equation for the analytical quantification of each purine compound. System control, data acquisition and analysis are then performed. Applying this protocol, AMP, INO and ADO elute at 7, 11 and 11.9 min, respectively, and the total run time for each sample is 20 min. This protocol may be applied to different cell types and cell lines (both suspension and adherent), using culture media as matrix. The advantages are easy and fast sample preparation and the requirement of a small amount of supernatant for analysis. Furthermore, the use of a serum-free medium allows skipping the protein precipitation step with acetonitrile that impacts the final concentration of purine compounds. One of the limitations of the method is the requirement of the equilibration column run before each single sample run, making the total run time of the experiment longer and preventing high throughput screening applications.

Adenosine (ADO) is a purine nucleoside with an adenine molecule attached to a ribose sugar molecule moiety through a glycosidic bond. When present in the extracellular environment, it protects cells from excessive damage by the action of the immune system. This role has been highlighted using different disease models, such as colitis1, diabetes2, asthma3, sepsis4, and ischemic injury5. One of the main ADO functions is the inhibition of immune responses in the tumor microenvironment, contributing to tumor immune evasion6. For this reason, the mechanisms involved in ADO formation and signaling are of cons....

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CLL blood samples are obtained in accordance with Institutional Guidelines and Declaration of Helsinki.

1. Isolation of Leukemic Lymphocytes from Blood Samples of CLL Patients 

  1. Collect blood sample in sodium heparin (green-top) tube17.
  2. Make 1: 3 dilution of whole blood with RT 1x phosphate buffered saline (PBS).
  3. Purify peripheral blood mononuclear cells (PBMC) from blood samples by density gradient centrifugation.
    1. Underlay 5 ml of density centrifugation m.......

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To evaluate the percentage (%) of leukemic cells in freshly purified PBMCs from a representative CLL patient, cells are marked with anti-CD19 and anti-CD5 antibodies. The left panel of Figure 3 represents a cytofluorimetric dot plot with a selective gate on live cells. Figure 3 shows an example of PBMC from a CLL patient before (middle panel) and after (right panel) B cell purification.

An examp.......

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The protocol described here permits to evaluate the activity of the CD39/CD73 adenosinergic machinery in cell culture media from purified human leukemic cells. Through this HPLC method we can follow and quantitatively measure the enzymatic generation of ADO (CD73-dependent) and its subsequent degradation to INO (CD26/ADA dependent). The use of enzyme inhibitors allows to control the protocol and to have internal controls. The advantages and novelties of this protocol are that i) it may be applied to cells that are growin.......

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This work is supported by Associazione Italiana Ricerca Cancro (IG #12754).

....

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Name Company Catalog Number Comments
Human blood
Milli-Q water Millipore double deionised water
Ficoll-Paque Plus GE-Healthcare 17-1440-03
purified anti-CD3, -CD14, -CD16 made in-house mouse monoclonal
PE-labeled anti-CD19 Miltenyi Biotec 120-014-229
FITC-labeled anti-CD5 Miltenyi Biotec 130-096-574
Dynabeads sheep anti-mouse IgG Invitrogen 11031
Phosphate-buffered saline (PBS) Amresco E404-200TABS tablets
bovine serum albumin (BSA) ID bio 1000-70 standard grade
isolation buffer PBS 0.1 % BSA 2 mM EDTA, pH 7.4
AIM V serum free medium GIBCO 12055-091 liquid (research grade)
adenosine 5’-diphosphate (ADP) Sigma-Aldrich A2754
adenosine 5’-monosphate (AMP) Sigma-Aldrich A1752
adenosine (ADO) Sigma-Aldrich A9251
inosine (INO) Sigma-Aldrich I4125
α,β-methylene-ADP (APCP) Sigma-Aldrich M8386 CD73 inhibitor
EHNA hydrochloride Sigma-Aldrich E114 adenosine deaminase inhibitor
Deoxycoformycin (dCF) Tocris 2033 adenosine deaminase inhibitor
Dimethyl sulfoxide (DMSO) Sigma-Aldrich D2650
Dipyridamole Sigma-Aldrich D9766 nucleoside transporter inhibitor
acetonitrile (CHROMASOLV Plus) Sigma-Aldrich 34998 HPLC-grade
ammonium acetate Sigma-Aldrich 9688 7 mM, pH 3.0
hydrochloric acid Sigma-Aldrich 30721-1L min. 37 %
Name Company Catalog Number Comments
Equipment
Bürker cell counter VWR 631-0920 hemocytometer
DynaMag-15 Magnet Invitrogen 12301D Dynal magnetic bead separator
microcentrifuge safe-lock tubes Eppendorf 030-120-0086 1.5 ml
PET centrifuge tubes Corning 430053/430304 15 – 50 ml
Minisart RC4 syringe filters Sartorius Stedim Biotech 17821 membrane 0.2 µm
short thread vials VWR 548-0029 1.5 ml/glass
micro-inserts VWR 548-0006 0.1 ml/glass
screw caps VWR 548-0085 9 mm/PP blue
Atlantis dC18 Column Waters 186001344 5 µm, 4.6 x 150 mm
Atlantis dC18 Guard Column Waters 186001323 5 µm, 4.6 x 20 mm
Waters Alliance 2965 Separations Module Waters HPLC separation module
Waters 2998 Photodiode Array (PDA) Detector Waters UV detector
Waters Empower2 software Waters

  1. Naganuma, M., Wiznerowicz, E. B., Lappas, C. M., Linden, J., Worthington, M. T., Ernst, P. B. Cutting edge: Critical role for A2A adenosine receptors in the T cell-mediated regulation of colitis. J Immunology. 177 (5), 2765-2769 (2006).
  2. Nemeth, Z. H., et al. Adenosine receptor activation ameliorates type 1 diabetes. FASEB J. 21 (10), 2379-2388 (2007).
  3. Fan, M., Jamal Mustafa, S. Role of adenosine in airway inflammation in an allergic mouse model of asthma. Int Immunopharmacol. 6 (1), 36-45 (2006).
  4. Csoka, B., et al. A2B adenosine receptors protect against sepsis-induced mortality by dampening excessive inflammation. J Immunol. 185 (1), 542-550 (2010).
  5. Peart, J. N., Headrick, J. P. Adenosinergic cardioprotection: multiple receptors, multiple pathways. Pharmacol Ther. 114 (2), 208-221 (2007).
  6. Ohta, A., et al. A2A adenosine receptor protects tumors from antitumor T cells. Proc Natl Acad Sci U S A. 103 (35), 13132-13137 (2006).
  7. Hasko, G., Linden, J., Cronstein, B., Pacher, P. Adenosine receptors: therapeutic aspects for inflammatory and immune diseases. Nat Rev Drug Discov. 7 (9), 759-770 (2008).
  8. Cronstein, B. N. Adenosine, an endogenous anti-inflammatory agent. J Appl Physiol (1985). 76 (1), 5-13 (1994).
  9. Molina-Arcas, M., Casado, F. J., Pastor-Anglada, M. Nucleoside transporter proteins. Curr Vasc Pharmacol. 7 (4), 426-434 (2009).
  10. Deaglio, S., et al. Adenosine generation catalyzed by CD39 and CD73 expressed on regulatory T cells mediates immune suppression. J Exp Med. 204 (6), 1257-1265 (2007).
  11. Linden, J. Regulation of leukocyte function by adenosine receptors. Adv Pharmacol. 61, 95-114 (2011).
  12. Antonioli, L., Blandizzi, C., Pacher, P., Hasko, G. Immunity, inflammation and cancer: a leading role for adenosine. Nat Rev Cancer. 13 (12), 842-857 (2013).
  13. Antonioli, L., Csoka, B., Fornai, M., et al. Adenosine and inflammation: what's new on the horizon. Drug Discov Today. 19 (8), 1051-1068 (1051).
  14. Chiorazzi, N., Rai, K. R., Ferrarini, M. Chronic lymphocytic leukemia. N Engl J Med. 352 (8), 804-815 (2005).
  15. Abousamra, N. K., Salah El-Din, M., Hamza Elzahaf, E., Esmael, M. E. Ectonucleoside triphosphate diphosphohydrolase-1 (E-NTPDase1/CD39) as a new prognostic marker in chronic lymphocytic leukemia. Leuk Lymphoma. 56 (1), 113-119 (2015).
  16. Serra, S., et al. CD73-generated extracellular adenosine in chronic lymphocytic leukemia creates local conditions counteracting drug-induced cell death. Blood. 118 (23), 6141-6152 (2011).
  17. Chen, L. S., Keating, M. J., Gandhi, V. Blood collection methods affect cellular protein integrity: implications for clinical trial biomarkers and ZAP-70 inn CLL. Blood. 124 (7), 1192-1195 (2014).
  18. Kalina, T., et al. EuroFlow standardization of flow cytometer instrument settings and immunophenotyping protocols. Leukemia. 26 (9), 1986-2010 (2012).
  19. Deaglio, S., et al. CD38 and ZAP-70 are functionally linked and mark CLL cells with high migratory potential. Blood. 110 (12), 4012-4021 (2007).
  20. Sachsenmeier, K. F., et al. Development of a novel ectonucleotidase assay suitable for high-throughput screening. J Biomol Screen. 17 (7), 993-998 (2012).

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