title: [Determination and significance of interleukin-16 in tuberculous and malignant pleural effusion].
abstract: OBJECTIVE
  Interleukin-16 (IL-16) is a chemoattractant of CD4+ lymphocytes, and it has been implicated in the pathogenesis of various inflammatory diseases. The aim of the present study was to measure IL-16 in pleural effusions caused by tuberculosis and malignancy and its relationship with cell and differential counts as well as lymphocyte subsets.
  
  
  METHODS
  Pleural effusion and venous blood samples were collected from 32 patients with tuberculous pleuritis and 30 lung cancer patients with malignant effusion. Analysis of pleural effusion for total leukocytes and cell differentials of leukocytes was performed. Three-color flow cytometry was performed to determine T lymphocyte subsets in cell pellets of pleural effusion. The concentration of IL-16 in cell-free supernatants of pleural effusion and sera was measured by a sandwich enzyme-linked immunosorbent assay.
  
  
  RESULTS
  In all the studied patients, the level of IL-16 was significantly higher in pleural effusion than in serum. The levels of IL-16 were significantly higher in tuberculous than in malignant effusions. In pleural effusion, positive correlations were found between the IL-16 levels and total cell counts, lymphocytes, CD3+ T cells, as well as CD4+ T cells.
  
  
  CONCLUSIONS
  Compared to malignant pleural effusion, IL-16 appeared to be increased in tuberculous pleural effusion. The pleural effusion IL-16 levels were positively related to the numbers of CD4+ T cells, suggesting that IL-16 might be capable of inducing CD4+ T cell infiltration into pleural space.
authors.affiliation: People's Hospital of Pingnan, Guangxi 530000, China.
authors.forename: Ze-xin
authors.initials: ZX
authors.lastname: Huang
authors.forename: Huan-zhong
authors.initials: HZ
authors.lastname: Shi
authors.forename: Lan-fu
authors.initials: LF
authors.lastname: Kang
authors.forename: Xue-jun
authors.initials: XJ
authors.lastname: Qin
authors.forename: Wu-ning
authors.initials: WN
authors.lastname: Mo
authors.forename: Yi-qiang
authors.initials: YQ
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D019410:Interleukin-16 / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000276:immunology* / Q000378:metabolism; D016066:Pleural Effusion, Malignant / Q000276:immunology* / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014396:Tuberculosis, Pleural / Q000276:immunology* / Q000378:metabolism
chemical_list: D019410:Interleukin-16