Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome

Lawrence M Schopfer, Patrick Masson, Patricia Lamourette, Stéphanie Simon, Oksana Lockridge

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Flight crews complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MSMS) on the Triple TOF 5600 mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 (Ser198) was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum, the limit of detection was 0.1% cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2 × 10-9 g in 0.5 ml or 23 × 10-15 moles of inhibited BChE in 0.5 ml of plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels.

Original languageEnglish (US)
Pages (from-to)17-26
Number of pages10
JournalAnalytical Biochemistry
Volume461
DOIs
StatePublished - Sep 15 2014

Fingerprint

Plasma (human)
Butyrylcholinesterase
Phosphates
Plasmas
Mass spectrometry
Ions
Phosphoserine
Cyanogen Bromide
Jet engines
Fumes
Aircraft
Poisons
Pepsin A
Liquid chromatography
Mass spectrometers
Tandem Mass Spectrometry
Liquid Chromatography
Acetic Acid
Sepharose
Serine

Keywords

  • Aerotoxic syndrome
  • Butyrylcholinesterase
  • Mass spectrometry
  • Monoclonal antibody mAb2

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome. / Schopfer, Lawrence M; Masson, Patrick; Lamourette, Patricia; Simon, Stéphanie; Lockridge, Oksana.

In: Analytical Biochemistry, Vol. 461, 15.09.2014, p. 17-26.

Research output: Contribution to journalArticle

@article{4b565618501d497287be8fc6dfabe1b7,
title = "Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome",
abstract = "Flight crews complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MSMS) on the Triple TOF 5600 mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 (Ser198) was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum, the limit of detection was 0.1{\%} cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2 × 10-9 g in 0.5 ml or 23 × 10-15 moles of inhibited BChE in 0.5 ml of plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels.",
keywords = "Aerotoxic syndrome, Butyrylcholinesterase, Mass spectrometry, Monoclonal antibody mAb2",
author = "Schopfer, {Lawrence M} and Patrick Masson and Patricia Lamourette and St{\'e}phanie Simon and Oksana Lockridge",
year = "2014",
month = "9",
day = "15",
doi = "10.1016/j.ab.2014.05.021",
language = "English (US)",
volume = "461",
pages = "17--26",
journal = "Analytical Biochemistry",
issn = "0003-2697",
publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome

AU - Schopfer, Lawrence M

AU - Masson, Patrick

AU - Lamourette, Patricia

AU - Simon, Stéphanie

AU - Lockridge, Oksana

PY - 2014/9/15

Y1 - 2014/9/15

N2 - Flight crews complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MSMS) on the Triple TOF 5600 mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 (Ser198) was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum, the limit of detection was 0.1% cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2 × 10-9 g in 0.5 ml or 23 × 10-15 moles of inhibited BChE in 0.5 ml of plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels.

AB - Flight crews complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MSMS) on the Triple TOF 5600 mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 (Ser198) was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum, the limit of detection was 0.1% cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2 × 10-9 g in 0.5 ml or 23 × 10-15 moles of inhibited BChE in 0.5 ml of plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels.

KW - Aerotoxic syndrome

KW - Butyrylcholinesterase

KW - Mass spectrometry

KW - Monoclonal antibody mAb2

UR - http://www.scopus.com/inward/record.url?scp=84898469759&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84898469759&partnerID=8YFLogxK

U2 - 10.1016/j.ab.2014.05.021

DO - 10.1016/j.ab.2014.05.021

M3 - Article

C2 - 24892986

AN - SCOPUS:84898469759

VL - 461

SP - 17

EP - 26

JO - Analytical Biochemistry

JF - Analytical Biochemistry

SN - 0003-2697

ER -