Original Research ARTICLE

Front. Oncol., 10 January 2012 | http://dx.doi.org/10.3389/fonc.2011.00053

Decreased numbers of CD4+ naive and effector memory T cells, and CD8+ naïve T cells, are associated with trichloroethylene exposure

H. Dean Hosgood III1*, Luoping Zhang2, Xiaojiang Tang3*, Roel Vermeulen4, Chuangyi Qiu3, Min Shen1, Martyn T. Smith2, Yichen Ge3, Zhiying Ji2, Jun Xiong5, Jian He6, Boris Reiss4, Songwang Liu7, Yuxuan Xie3, Weihong Guo2, Noe Galvan2, Laiyu Li3, Zhenyue Hao8†, Nathaniel Rothman1†, Hanlin Huang3† and Qing Lan1†
  • 1 Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
  • 2 School of Public Health, University of California at Berkeley, Berkeley, CA, USA
  • 3 Guangdong Poison Control Center, Guangdong, China
  • 4 Utrecht University, Utrecht, Netherlands
  • 5 Dongguan Center for Disease Control and Prevention, Guangdong, China
  • 6 Zhongshan Center for Disease Control and Prevention, Guangdong, China
  • 7 Qiaotou Hospital, Dongguan, China
  • 8 The Campbell Family Institute for Cancer Research, University Health Network, Toronto, ON, Canada

Trichloroethylene (TCE) is a volatile chlorinated organic compound that is commonly used as a solvent for lipophilic compounds. Although recognized as an animal carcinogen, TCE’s carcinogenic potential in humans is still uncertain. We have carried out a cross-sectional study of 80 workers exposed to TCE and 96 unexposed controls matched on age and sex in Guangdong, China to study TCE’s early biologic effects. We previously reported that the total lymphocyte count and each of the major lymphocyte subsets (i.e., CD4+ T cells, CD8+ T cells, natural killer cells, and B cells) were decreased in TCE-exposed workers compared to controls, suggesting a selective effect on lymphoid progenitors, and/or lymphocyte survival. To explore which T lymphocyte subsets are affected in the same study population, we investigated the effect of TCE exposure on the numbers of CD4+ naïve and memory T cells, CD8+ naïve and memory T cells, and regulatory T cells by FACS analysis. Linear regression of each subset was used to test for differences between exposed workers and controls adjusting for potential confounders. We observed that CD4+ and CD8+ naïve T cell counts were about 8% (p = 0.056) and 17% (p = 0.0002) lower, respectively, among exposed workers. CD4+ effector memory T cell counts were decreased by about 20% among TCE-exposed workers compared to controls (p = 0.001). The selective targeting of TCE on CD8+ naive and possibly CD4+ naive T cells, and CD4+ effector memory T cells, provide further insights into the immunosuppression-related response of human immune cells upon TCE exposure.

Keywords: trichloroethylene, lymphocyte, CD4, CD8, naïve, memory

Citation: Hosgood III HD, Zhang L, Tang X, Vermeulen R, Qiu C, Shen M, Smith MT, Ge Y, Ji Z, Xiong J, He J, Reiss B, Liu S, Xie Y, Guo W, Galvan N, Li L, Hao Z, Rothman N, Huang H and Lan Q (2012) Decreased numbers of CD4+ naive and effector memory T cells, and CD8+ naïve T cells, are associated with trichloroethylene exposure. Front. Oncol. 1:53. doi: 10.3389/fonc.2011.00053

Received: 29 July 2011; Accepted: 04 December 2011;
Published online: 10 January 2012.

Edited by:

Mohandas K. Mallath, Tata Memorial Centre, India

Reviewed by:

Wagner Ricardo Montor, Faculdade de Ciências Médicas da Santa Casa de São Paulo, Brazil
Jie Lin, The University of Texas MD Anderson Cancer Center, USA

Copyright: © 2012 Hosgood III, Zhang, Tang, Vermeulen, Qiu, Shen, Smith, Ge, Ji, Xiong, He, Reiss, Liu, Xie, Guo, Galvan, Li, Hao, Rothman, Huang and Lan. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.

*Correspondence: H. Dean Hosgood III, Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Blvd., EPS 8120, MCS 7240, Bethesda, MD 20892-7240, USA. e-mail: hosgoodd@mail.nih.gov; Xiaojiang Tang, Guangdong Medical Laboratory Animal Center, 119 Poyang Road, Nanhai District, Foshan, Guangdong 528248, China. e-mail: river-t@126.com

Zhenyue Hao, Nathaniel Rothman, Hanlin Huang and Qing Lan have contributed equally to this work.