Chlorpyrifos induces apoptosis in human T cells

Toxicology. 2009 Jan 8;255(1-2):53-7. doi: 10.1016/j.tox.2008.10.003. Epub 2008 Oct 17.

Abstract

It was found previously that organophosphorus pesticides (OPs) significantly inhibited cytotoxic T lymphocyte (CTL) activity. To explore the mechanism of OP-induced inhibition of CTL activity, the present study investigated whether OPs can induce cell death/apoptosis in T cells. Jurkat human T cells were treated with chlorpyrifos at 0-100 ppm for 2, 4, and 6h at 37 degrees C in vitro. It was found that chlorpyrifos induced cell death of Jurkat human T cells in a dose- and time-dependent manner, as shown by MTT and LDH assays. Then, it was investigated if chlorpyrifos-induced cell death consisted of apoptosis, as determined by analysis of Annexin-V staining and the intracellular level of active caspase-3 by flow cytometry, and DNA fragmentation analysis. It was found that chlorpyrifos induces apoptosis in Jurkat T cells in a dose- and time-dependent manner, as determined by analysis of Annexin-V staining. DNA fragmentation was detected when cells were treated with 50 or 100 ppm chlorpyrifos for 4 and 6h. Chlorpyrifos also induced an increase in intracellular active caspase-3 in Jurkat T cells in a dose- and time-dependent manner, and a caspase-3 inhibitor, Z-DEVD-FMK, significantly inhibited chlorpyrifos-induced apoptosis. These findings indicate that chlorpyrifos can induce apoptosis in human Jurkat T cell cells, and this effect is partially mediated by the activation of intracellular caspase-3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Annexin A5
  • Apoptosis / drug effects*
  • Caspase 3 / metabolism
  • Cell Death / drug effects
  • Chlorpyrifos / toxicity*
  • DNA / biosynthesis
  • DNA / isolation & purification
  • DNA Fragmentation / drug effects
  • Fluorescein-5-isothiocyanate
  • Fluorescent Dyes
  • Humans
  • Indicators and Reagents
  • Insecticides / toxicity*
  • Jurkat Cells
  • L-Lactate Dehydrogenase / metabolism
  • T-Lymphocytes / drug effects*
  • Tetrazolium Salts
  • Thiazoles

Substances

  • Annexin A5
  • Fluorescent Dyes
  • Indicators and Reagents
  • Insecticides
  • Tetrazolium Salts
  • Thiazoles
  • DNA
  • L-Lactate Dehydrogenase
  • Caspase 3
  • thiazolyl blue
  • Fluorescein-5-isothiocyanate
  • Chlorpyrifos