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Analysis of Electrophysiological Properties and Responses of Neutrophils

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Neutrophil Methods and Protocols

Part of the book series: Methods in Molecular Biology ((MIMB,volume 1124))

Abstract

The past decade has seen increasing use of the patch-clamp technique on neutrophils and eosinophils. The main goal of these electrophysiological studies has been to elucidate the mechanisms underlying the phagocyte respiratory burst. NADPH oxidase activity, which defines the respiratory burst in granulocytes, is electrogenic because electrons from NADPH are transported across the cell membrane, where they reduce oxygen to form superoxide anion (O2 −). This passage of electrons comprises an electrical current that would rapidly depolarize the membrane if the charge movement were not balanced by proton efflux. The patch-clamp technique enables simultaneous recording of NADPH oxidase-generated electron current and H+ flux through the closely related H+ channel. Increasing evidence suggests that other ion channels may play crucial roles in degranulation, phagocytosis, and chemotaxis, highlighting the importance of electrophysiological studies to advance knowledge of granulocyte function. Several configurations of the patch-clamp technique exist. Each has advantages and limitations that are discussed here. Meaningful measurements of ion channels cannot be achieved without an understanding of their fundamental properties. We describe the types of measurements that are necessary to characterize a particular ion channel.

AA arachidonic acid, DPI diphenylene iodonium, g H proton conductance, O 2 ●− superoxide anion, pH i intracellular pH, pH o extracellular pH, PKC protein kinase C, PMA phorbol myristate acetate, TEA + tetraethylammonium ion, TMA + tetramethylammonium, ATP adenosine triphosphate, GTPγs guanosine triphosphate γs, V rev reversal potential, V hold holding potential, V threshold channel opening potential, g H proton conductance, τ act time constant of activation, P open open probability, I hold holding current, I e electron current, E H equilibrium potential for protons, γ single channel conductance

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Acknowledgements

This work was supported in part by NIH grants HL61437 and GM087507 and NSF grant MCB-0943362.

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Authors and Affiliations

  1. Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, IL, USA

    Deri Morgan & Thomas E. DeCoursey

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  1. Deri Morgan
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  2. Thomas E. DeCoursey
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Editors and Affiliations

  1. Montana State University Dept. Veterinary Molecular Biology, Bozeman, Montana, USA

    Mark T. Quinn

  2. Lab. Human Bacterial Pathogenesis, National Institutes of Health Nat. Inst. Allergy & Infectious Diseases, Hamilton, Montana, USA

    Frank R. DeLeo

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Morgan, D., DeCoursey, T.E. (2014). Analysis of Electrophysiological Properties and Responses of Neutrophils. In: Quinn, M., DeLeo, F. (eds) Neutrophil Methods and Protocols. Methods in Molecular Biology, vol 1124. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-62703-845-4_9

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