Quantitation of ortho-Cresyl Phosphate Adducts to Butyrylcholinesterase in Human Serum by Immunomagnetic-UHPLC-MS/MS

Details

• Alternative Title:
  J Mass Spectrom
• Personal Author:
  Johnson, Darryl ; Carter, Melissa D. ; Crow, Brian S. ; Isenberg, Samantha L. ; Graham, Leigh Ann ; Erol, H. Akin ; Watson, Caroline M. ; Pantazides, Brooke G. ; van der Schans, Marcel J. ; Langenberg, Jan P. ; Noort, Daan ; Blake, Thomas A. ; Thomas, Jerry D. ; Johnson, Rudolph C.
• Description:
  Tri-ortho-cresyl phosphate (ToCP) is an anti-wear, flame retardant additive used in industrial lubricants, hydraulic fluids and gasoline. The neurotoxic effects of ToCP arise from the liver-activated metabolite 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (cresyl saligenin phosphate or CBDP), which inhibits esterase enzymes including butyrylcholinesterase (BChE). Following BChE adduction, CBDP undergoes hydrolysis to form the aged adduct ortho-cresyl phosphoserine (oCP-BChE), thus providing a biomarker of CBDP exposure. Previous studies have identified ToCP in aircraft cabin and cockpit air, but assessing human exposure has been hampered by the lack of a laboratory assay to confirm exposure. This work presents the development of an immunomagnetic-UHPLC-MS/MS method for the quantitation of unadducted BChE and the long-term CBDP biomarker, oCP-BChE, in human serum. The method has a reportable range from 2.0 ng/ml to 150 ng/ml, which is consistent with the sensitivity of methods used to detect organophosphorus nerve agent protein adducts. The assay demonstrated high intraday and interday accuracy (≥85%) and precision (RSD ≤ 15%) across the calibration range. The method was developed for future analyses of potential human exposure to CBDP. Analysis of human serum inhibited in vitro with CBDP demonstrated that the oCP-BChE adduct was stable for at least 72 h at 4, 22 and 37 °C. Compared to a previously reported assay, this method requires 75% less sample volume, reduces analysis time by a factor of 20 and demonstrates a threefold improvement in sensitivity. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
• Subjects:
  Butyrylcholinesterase Chromatography, High Pressure Liquid Humans Immunomagnetic Separation Limit Of Detection Reproducibility Of Results Tandem Mass Spectrometry Tritolyl Phosphates
• Keywords:
  Butyrylcholinesterase Cresyl Saligenin Phosphate Jamaica Ginger Paralysis Organophosphate-induced Delayed Neuropathy Tri-ortho-cresyl-phosphate
• Source:
  J Mass Spectrom. 50(4):683-692
• Pubmed ID:
  26149113
• Pubmed Central ID:
  PMC5713888
• Document Type:
  Journal Article
• Funding:
  CC999999/Intramural CDC HHSUnited States/
• Volume:
  50
• Issue:
  4
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:146b6983fb86cacaa3c467a6a65e3cb0646f49e5c9576ecfae6e76e200c4556f
• Download URL:
  https://stacks.cdc.gov/view/cdc/50475/cdc_50475_DS1.pdf
• File Type:
  [PDF - 962.50 KB ]