title: Native soluble carcinoembryonic antigen is not involved in the impaired activity of CD56 natural killer cells in malignant pleural effusion.
abstract: BACKGROUND
  Natural killer (NK) cells are lymphocytes of the innate immune system that play a crucial role in tumor immune surveillance. Accumulated data indicated that NK cells in the tumor microenvironment often display a suppressed function. However, the mechanism is not clear.
  
  
  OBJECTIVE
  In this study, the effects and relative mechanisms of malignant pleural effusion (MPE) from patients with lung cancer on NK cells were researched.
  
  
  METHODS
  MPE and peripheral blood (PB) samples were collected from patients with lung cancer. The cytotoxic activity of CD56(dim) NK cells in PB and MPE mononuclear cells was analyzed by ﬂow cytometry.
  
  
  RESULTS
  It was observed that the percentages of total NK cells and a CD56(dim) NK subset in MPE reduced accompanying impaired cytotoxic activity compared with that in paired PB. Cell-free MPE treatment reduced both the proportion and cytotoxic activity of CD56(dim) NK cells in PB from healthy donors. The suppression effects were not based on soluble carcinoembryonic antigen and the inhibitory cytokines interleukin-10 and transforming growth factor-β1, but were dependent on the factor with a molecular weight >100 kDa.
  
  
  CONCLUSIONS
  These results demonstrated that native soluble carcinoembryonic antigen does not suppress the activity of NK cells, and an unknown factor with a molecular weight >100 kDa plays a critical role in the impairment of CD56(dim) NK cells in MPE, which might lead to tumor progression.
authors.affiliation: Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Qi
authors.forename: Daling
authors.initials: D
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.forename: Shuo
authors.initials: S
authors.lastname: Yang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Su
authors.forename: Min
authors.initials: M
authors.lastname: Fang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Tan
authors.forename: Huanzhong
authors.initials: H
authors.lastname: Shi
authors.forename: XiYun
authors.initials: X
authors.lastname: Yan
authors.forename: Feili
authors.initials: F
authors.lastname: Gong
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019002:CD56 Antigen / Q000378:metabolism; D002272:Carcinoembryonic Antigen / Q000502:physiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D016753:Interleukin-10 / Q000502:physiology; D007694:Killer Cells, Natural / Q000378:metabolism / Q000473:pathology / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016066:Pleural Effusion, Malignant / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D053773:Transforming Growth Factor beta1 / Q000502:physiology
chemical_list: D019002:CD56 Antigen; D002272:Carcinoembryonic Antigen; C508609:IL10 protein, human; C522918:NCAM1 protein, human; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10