Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca<sup>2+</sup>-activated Cl<sup>-</sup> Channels

Leïla Staali; Didier André Colin

doi:doi:10.11648/j.ijmb.20200503.16

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Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca²⁺-activated Cl^- Channels

Leïla Staali, Didier André Colin

Published in International Journal of Microbiology and Biotechnology (Volume 5, Issue 3)

Received: 1 June 2020 Accepted: 15 June 2020 Published: 29 June 2020

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Abstract

The bi-component leukotoxins; γ-hemolysin and Panton and Valentin Leukocidin (PVL) from Staphylococcus aureus induce two independent cellular events 1) the formation of trans-membrane pores not permeable to chloride (Cl^-) ions and 2) the activation of at least, two modes of chloride fluxes (efflux/influx), including pre-existing Ca²⁺-activated Cl^- channels (CaCC) in human polymorphonuclear neutrophils (PMNs). This was investigated by using spectrofluorometry techniques and the chloride-sensitive quencher fluorescent indicator, MQAE (N-(6-methoxyquinolyl) acetoacethyl ester). The ethidium bromide was used as an indicator for the trans-membrane pores formation by staphylococcal leukotoxins. In the absence of extracellular Ca²⁺, HlgA/HlgB, HlgC/HlgB and LukS-PV/LukF-PV leukotoxins from S. aureus induced a massive efflux of chloride (Cl^-) ions. Interestingly, in the presence of extracellular Ca²⁺, the HlgA/HlgB γ-hemolysin provoked a biphasic response of Cl^- movements (efflux/influx). Conversely to HlgA/HlgB and LukS-PV/LukF-PV, HlgC/HlgB leukotoxins did not induce any Cl^- movement under this condition (e.g. in the presence of extracellular Ca²⁺). The potent Cl^- channel inhibitor, DIDS, did inhibit significantly the Cl^- fluxes caused by all pairs of staphylococcal leukotoxins tested in both conditions. In the present study, we found that the inhibitory effect of flufenamic acid, known as a Cl^- channel inhibitor, was restricted only to the Ca²⁺-dependent Cl^- influx triggered only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins. These findings might suggest that, Cl^- fluxes in human neutrophils did involve at least, two different types of Cl^- pathways, depending on the absence or presence of extracellular Ca²⁺. Both Cl^- channels blockers, DIDS and flufenamic acid did not alter the pores formation by staphylococcal leukotoxins. Furthermore, under conditions when the membrane pores formation was blocked by divalent ions (Ca²⁺ and/or Zn²⁺), Cl^- ions movements were still observed. Taken together, our results strongly provide an evidence that: i) trans-membrane pores formed by staphylococcal leukotoxins: HlgA/HlgB, HlgC/HlgB (γ-hemolysin) and LukS-PV/LukF-PV (PVL) do not drive Cl^- ions fluxes ii) at least, two different types of Cl^- ions pathways are activated, depending on the absence or presence of extracellular Ca²⁺, including Ca²⁺-activated Cl^- channels (CaCC) and, iii) Ca²⁺-activated Cl^- channels are mediated only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins.

Published in	International Journal of Microbiology and Biotechnology (Volume 5, Issue 3)
DOI	10.11648/j.ijmb.20200503.16
Page(s)	110-119
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2020. Published by Science Publishing Group

Keywords

Pore-forming Toxin, S. aureus, Leukotoxin, Cl ^- channels, γ-hemolysin, Panton-Valentin Leukocidin, Neutrophils, Spectrofluorometry

References

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[2]	Finck-Barbancon V, Prévost G, Piémont Y (1991) Improved purification of leukocidin from Staphylococcus aureus and toxin distribution among hospital strains. Res. Microbiol. 142: 75-85.
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[6]	Guaduchon V, Werner S, Prévost G, Monteil H, Colin DA (2001) Flow cytometry determination of Panton-Valentin leukocidin S component binding. Infect. Immun. 69: 2390-2395.
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[12]	Staali L, Colin DA (2020) The pore-forming leukotoxins from S. aureus involve Ca²⁺-activated Ca²⁺ channels and other types of Ca²⁺ channels in Ca²⁺ entry into neutrophils. International Journal of Microbiology and Biotechnology. 5 (2): 55-68.
[13]	Colin DA, Monteil H (2003) Control of the oxidative burst of human neutrophils by staphylococcal leukotoxins. Infection and Immunity. 71 (7): 3724-3729.
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[21]	Shimizu Y, Daniels RH, Elmore MA, Finnen MJ, Hill ME, Lackie JM (1993) Agonist-stimuated Cl- efflux from human neutrophils: a common phenomenon during neutrophil activation. Biochem. Pharmacol. 45: 1743-1751.
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[28]	Menegazzi R, Busetto S, Decleva E, Cramer R, Dri P, Patriarca P (1999) Triggering of chloride ion efflux from human neutrophils as a novel function of leukocyte β2 intergrins: relationship with spreading and activation of the respiratory burst. J. immunol. 162: 423-434.
[29]	Engblom AC, Akerman KE (1993) Determination of the intracellular free chloride concentration in rat brain synaptoneurosomes using a chloride-sensitive fluorescent indicator. Biochem. Biophys. Acta 1153 (2): 262-266.
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[33]	Simchowitz L, Bibb JA (1990) Functional analysis of the modes of anion transport in neutrophils and HL-60 cells. Annu. Rev. Physiol. 52: 381-397.
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[36]	Kankaanranta H, Moilanen E (1995) Flufenamic and tolfenamic acids inhibit calcium influx in human polymorphonuclear leukocytes. Mol. Pharmacol. 47: 1006-1013.
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Leïla Staali, Didier André Colin. (2020). Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. International Journal of Microbiology and Biotechnology, 5(3), 110-119. https://doi.org/10.11648/j.ijmb.20200503.16

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Leïla Staali; Didier André Colin. Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. Int. J. Microbiol. Biotechnol. 2020, 5(3), 110-119. doi: 10.11648/j.ijmb.20200503.16

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Leïla Staali, Didier André Colin. Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. Int J Microbiol Biotechnol. 2020;5(3):110-119. doi: 10.11648/j.ijmb.20200503.16

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@article{10.11648/j.ijmb.20200503.16,
  author = {Leïla Staali and Didier André Colin},
  title = {Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels},
  journal = {International Journal of Microbiology and Biotechnology},
  volume = {5},
  number = {3},
  pages = {110-119},
  doi = {10.11648/j.ijmb.20200503.16},
  url = {https://doi.org/10.11648/j.ijmb.20200503.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmb.20200503.16},
  abstract = {The bi-component leukotoxins; γ-hemolysin and Panton and Valentin Leukocidin (PVL) from Staphylococcus aureus induce two independent cellular events 1) the formation of trans-membrane pores not permeable to chloride (Cl-) ions and 2) the activation of at least, two modes of chloride fluxes (efflux/influx), including pre-existing Ca2+-activated Cl- channels (CaCC) in human polymorphonuclear neutrophils (PMNs). This was investigated by using spectrofluorometry techniques and the chloride-sensitive quencher fluorescent indicator, MQAE (N-(6-methoxyquinolyl) acetoacethyl ester). The ethidium bromide was used as an indicator for the trans-membrane pores formation by staphylococcal leukotoxins. In the absence of extracellular Ca2+, HlgA/HlgB, HlgC/HlgB and LukS-PV/LukF-PV leukotoxins from S. aureus induced a massive efflux of chloride (Cl-) ions. Interestingly, in the presence of extracellular Ca2+, the HlgA/HlgB γ-hemolysin provoked a biphasic response of Cl- movements (efflux/influx). Conversely to HlgA/HlgB and LukS-PV/LukF-PV, HlgC/HlgB leukotoxins did not induce any Cl- movement under this condition (e.g. in the presence of extracellular Ca2+). The potent Cl- channel inhibitor, DIDS, did inhibit significantly the Cl- fluxes caused by all pairs of staphylococcal leukotoxins tested in both conditions. In the present study, we found that the inhibitory effect of flufenamic acid, known as a Cl- channel inhibitor, was restricted only to the Ca2+-dependent Cl- influx triggered only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins. These findings might suggest that, Cl- fluxes in human neutrophils did involve at least, two different types of Cl- pathways, depending on the absence or presence of extracellular Ca2+. Both Cl- channels blockers, DIDS and flufenamic acid did not alter the pores formation by staphylococcal leukotoxins. Furthermore, under conditions when the membrane pores formation was blocked by divalent ions (Ca2+ and/or Zn2+), Cl- ions movements were still observed. Taken together, our results strongly provide an evidence that: i) trans-membrane pores formed by staphylococcal leukotoxins: HlgA/HlgB, HlgC/HlgB (γ-hemolysin) and LukS-PV/LukF-PV (PVL) do not drive Cl- ions fluxes ii) at least, two different types of Cl- ions pathways are activated, depending on the absence or presence of extracellular Ca2+, including Ca2+-activated Cl- channels (CaCC) and, iii) Ca2+-activated Cl- channels are mediated only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins.},
 year = {2020}
}

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TY  - JOUR
T1  - Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels
AU  - Leïla Staali
AU  - Didier André Colin
Y1  - 2020/06/29
PY  - 2020
N1  - https://doi.org/10.11648/j.ijmb.20200503.16
DO  - 10.11648/j.ijmb.20200503.16
T2  - International Journal of Microbiology and Biotechnology
JF  - International Journal of Microbiology and Biotechnology
JO  - International Journal of Microbiology and Biotechnology
SP  - 110
EP  - 119
PB  - Science Publishing Group
SN  - 2578-9686
UR  - https://doi.org/10.11648/j.ijmb.20200503.16
AB  - The bi-component leukotoxins; γ-hemolysin and Panton and Valentin Leukocidin (PVL) from Staphylococcus aureus induce two independent cellular events 1) the formation of trans-membrane pores not permeable to chloride (Cl-) ions and 2) the activation of at least, two modes of chloride fluxes (efflux/influx), including pre-existing Ca2+-activated Cl- channels (CaCC) in human polymorphonuclear neutrophils (PMNs). This was investigated by using spectrofluorometry techniques and the chloride-sensitive quencher fluorescent indicator, MQAE (N-(6-methoxyquinolyl) acetoacethyl ester). The ethidium bromide was used as an indicator for the trans-membrane pores formation by staphylococcal leukotoxins. In the absence of extracellular Ca2+, HlgA/HlgB, HlgC/HlgB and LukS-PV/LukF-PV leukotoxins from S. aureus induced a massive efflux of chloride (Cl-) ions. Interestingly, in the presence of extracellular Ca2+, the HlgA/HlgB γ-hemolysin provoked a biphasic response of Cl- movements (efflux/influx). Conversely to HlgA/HlgB and LukS-PV/LukF-PV, HlgC/HlgB leukotoxins did not induce any Cl- movement under this condition (e.g. in the presence of extracellular Ca2+). The potent Cl- channel inhibitor, DIDS, did inhibit significantly the Cl- fluxes caused by all pairs of staphylococcal leukotoxins tested in both conditions. In the present study, we found that the inhibitory effect of flufenamic acid, known as a Cl- channel inhibitor, was restricted only to the Ca2+-dependent Cl- influx triggered only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins. These findings might suggest that, Cl- fluxes in human neutrophils did involve at least, two different types of Cl- pathways, depending on the absence or presence of extracellular Ca2+. Both Cl- channels blockers, DIDS and flufenamic acid did not alter the pores formation by staphylococcal leukotoxins. Furthermore, under conditions when the membrane pores formation was blocked by divalent ions (Ca2+ and/or Zn2+), Cl- ions movements were still observed. Taken together, our results strongly provide an evidence that: i) trans-membrane pores formed by staphylococcal leukotoxins: HlgA/HlgB, HlgC/HlgB (γ-hemolysin) and LukS-PV/LukF-PV (PVL) do not drive Cl- ions fluxes ii) at least, two different types of Cl- ions pathways are activated, depending on the absence or presence of extracellular Ca2+, including Ca2+-activated Cl- channels (CaCC) and, iii) Ca2+-activated Cl- channels are mediated only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins.
VL  - 5
IS  - 3
ER  -

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Leïla Staali
Didier André Colin

Bacteriology Institute of Medical Faculty, Louis Pasteur University, Strasbourg, France

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Leïla Staali, Didier André Colin. (2020). Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. International Journal of Microbiology and Biotechnology, 5(3), 110-119. https://doi.org/10.11648/j.ijmb.20200503.16

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Leïla Staali; Didier André Colin. Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. Int. J. Microbiol. Biotechnol. 2020, 5(3), 110-119. doi: 10.11648/j.ijmb.20200503.16

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AMA Style

Leïla Staali, Didier André Colin. Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels. Int J Microbiol Biotechnol. 2020;5(3):110-119. doi: 10.11648/j.ijmb.20200503.16

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@article{10.11648/j.ijmb.20200503.16,
  author = {Leïla Staali and Didier André Colin},
  title = {Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels},
  journal = {International Journal of Microbiology and Biotechnology},
  volume = {5},
  number = {3},
  pages = {110-119},
  doi = {10.11648/j.ijmb.20200503.16},
  url = {https://doi.org/10.11648/j.ijmb.20200503.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmb.20200503.16},
  abstract = {The bi-component leukotoxins; γ-hemolysin and Panton and Valentin Leukocidin (PVL) from Staphylococcus aureus induce two independent cellular events 1) the formation of trans-membrane pores not permeable to chloride (Cl-) ions and 2) the activation of at least, two modes of chloride fluxes (efflux/influx), including pre-existing Ca2+-activated Cl- channels (CaCC) in human polymorphonuclear neutrophils (PMNs). This was investigated by using spectrofluorometry techniques and the chloride-sensitive quencher fluorescent indicator, MQAE (N-(6-methoxyquinolyl) acetoacethyl ester). The ethidium bromide was used as an indicator for the trans-membrane pores formation by staphylococcal leukotoxins. In the absence of extracellular Ca2+, HlgA/HlgB, HlgC/HlgB and LukS-PV/LukF-PV leukotoxins from S. aureus induced a massive efflux of chloride (Cl-) ions. Interestingly, in the presence of extracellular Ca2+, the HlgA/HlgB γ-hemolysin provoked a biphasic response of Cl- movements (efflux/influx). Conversely to HlgA/HlgB and LukS-PV/LukF-PV, HlgC/HlgB leukotoxins did not induce any Cl- movement under this condition (e.g. in the presence of extracellular Ca2+). The potent Cl- channel inhibitor, DIDS, did inhibit significantly the Cl- fluxes caused by all pairs of staphylococcal leukotoxins tested in both conditions. In the present study, we found that the inhibitory effect of flufenamic acid, known as a Cl- channel inhibitor, was restricted only to the Ca2+-dependent Cl- influx triggered only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins. These findings might suggest that, Cl- fluxes in human neutrophils did involve at least, two different types of Cl- pathways, depending on the absence or presence of extracellular Ca2+. Both Cl- channels blockers, DIDS and flufenamic acid did not alter the pores formation by staphylococcal leukotoxins. Furthermore, under conditions when the membrane pores formation was blocked by divalent ions (Ca2+ and/or Zn2+), Cl- ions movements were still observed. Taken together, our results strongly provide an evidence that: i) trans-membrane pores formed by staphylococcal leukotoxins: HlgA/HlgB, HlgC/HlgB (γ-hemolysin) and LukS-PV/LukF-PV (PVL) do not drive Cl- ions fluxes ii) at least, two different types of Cl- ions pathways are activated, depending on the absence or presence of extracellular Ca2+, including Ca2+-activated Cl- channels (CaCC) and, iii) Ca2+-activated Cl- channels are mediated only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins.},
 year = {2020}
}

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TY  - JOUR
T1  - Bi-component Staphylococcal Leukotoxins Induce Chloride Ions Fluxes in Human Neutrophils: Opening of Ca2+-activated Cl- Channels
AU  - Leïla Staali
AU  - Didier André Colin
Y1  - 2020/06/29
PY  - 2020
N1  - https://doi.org/10.11648/j.ijmb.20200503.16
DO  - 10.11648/j.ijmb.20200503.16
T2  - International Journal of Microbiology and Biotechnology
JF  - International Journal of Microbiology and Biotechnology
JO  - International Journal of Microbiology and Biotechnology
SP  - 110
EP  - 119
PB  - Science Publishing Group
SN  - 2578-9686
UR  - https://doi.org/10.11648/j.ijmb.20200503.16
AB  - The bi-component leukotoxins; γ-hemolysin and Panton and Valentin Leukocidin (PVL) from Staphylococcus aureus induce two independent cellular events 1) the formation of trans-membrane pores not permeable to chloride (Cl-) ions and 2) the activation of at least, two modes of chloride fluxes (efflux/influx), including pre-existing Ca2+-activated Cl- channels (CaCC) in human polymorphonuclear neutrophils (PMNs). This was investigated by using spectrofluorometry techniques and the chloride-sensitive quencher fluorescent indicator, MQAE (N-(6-methoxyquinolyl) acetoacethyl ester). The ethidium bromide was used as an indicator for the trans-membrane pores formation by staphylococcal leukotoxins. In the absence of extracellular Ca2+, HlgA/HlgB, HlgC/HlgB and LukS-PV/LukF-PV leukotoxins from S. aureus induced a massive efflux of chloride (Cl-) ions. Interestingly, in the presence of extracellular Ca2+, the HlgA/HlgB γ-hemolysin provoked a biphasic response of Cl- movements (efflux/influx). Conversely to HlgA/HlgB and LukS-PV/LukF-PV, HlgC/HlgB leukotoxins did not induce any Cl- movement under this condition (e.g. in the presence of extracellular Ca2+). The potent Cl- channel inhibitor, DIDS, did inhibit significantly the Cl- fluxes caused by all pairs of staphylococcal leukotoxins tested in both conditions. In the present study, we found that the inhibitory effect of flufenamic acid, known as a Cl- channel inhibitor, was restricted only to the Ca2+-dependent Cl- influx triggered only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins. These findings might suggest that, Cl- fluxes in human neutrophils did involve at least, two different types of Cl- pathways, depending on the absence or presence of extracellular Ca2+. Both Cl- channels blockers, DIDS and flufenamic acid did not alter the pores formation by staphylococcal leukotoxins. Furthermore, under conditions when the membrane pores formation was blocked by divalent ions (Ca2+ and/or Zn2+), Cl- ions movements were still observed. Taken together, our results strongly provide an evidence that: i) trans-membrane pores formed by staphylococcal leukotoxins: HlgA/HlgB, HlgC/HlgB (γ-hemolysin) and LukS-PV/LukF-PV (PVL) do not drive Cl- ions fluxes ii) at least, two different types of Cl- ions pathways are activated, depending on the absence or presence of extracellular Ca2+, including Ca2+-activated Cl- channels (CaCC) and, iii) Ca2+-activated Cl- channels are mediated only by HlgA/HlgB and LukS-PV/LukF-PV leukotoxins.
VL  - 5
IS  - 3
ER  -

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