Expression of soluble Toll-like receptors in pleural effusions.
BACKGROUND
The Toll-like receptors (TLRs) represent a group of single-pass transmembrane receptors expressed on sentinel cells that are central to innate immune responses.The aim of this study was to investigate the presence of soluble TLRs in pleural effusions, and the diagnostic values of TLRs for pleural effusion with various etiologies.


METHODS
Pleural effusion and serum samples were collected from 102 patients (36 with malignant pleural effusion, 36 with tuberculous pleural effusion, 18 with bacterial pleural effusion, and 12 with transudative pleural effusion). The concentrations of TLR1 to TLR10 were determined in effusion and serum samples by enzyme linked immunosorbent assay. Four classical parameters (protein, lactate dehydrogenase, glucose and C-reactive protein (CRP)) in the pleural fluid were also assessed. Receiver-operating characteristic curves were used to assess the sensitivity and specificity of pleural fluid TLRs and biochemical parameters for differentiating bacterial pleural effusion.


RESULTS
The concentrations of TLR1, TLR3, TLR4, TLR7 and TLR9 in bacterial pleural effusion were significantly higher than those in malignant, tuberculous, and transudative groups, respectively. Analysis of receiver operating characteristic curves revealed that the area under the curves of TLR1, TLR3, TLR4, TLR7 and TLR9 were 0.831, 0.843, 0.842, 0.883 and 0.786, respectively, suggesting that these TLRs play a role in the diagnosis of bacterial pleural effusion. Also, the diagnostic value of TLRs for bacterial pleural effusions was much better than that of biochemical parameters (protein, lactate dehydrogenase, glucose and CRP).


CONCLUSIONS
The concentrations of TLR1, TLR3, TLR4, TLR7 and TLR9 appeared to be increased in bacterial pleural effusion compared to non-bacterial pleural effusions. Determination of these pleural TLRs may improve the ability of clinicians to differentiate pleural effusion patients of bacterial origin from those with other etiologies.
Yang
Hai-bo
HB
Department of Microbiology, Guangxi Medical University, China.
Xie
Kai-qing
KQ
Deng
Jing-min
JM
Qin
Shou-ming
SM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000378:metabolism* / Q000382:microbiology; D011446:Prospective Studies; D051194:Toll-Like Receptor 1 / Q000378:metabolism; D051196:Toll-Like Receptor 3 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D051199:Toll-Like Receptor 7 / Q000378:metabolism; D051217:Toll-Like Receptor 9 / Q000378:metabolism; D051193:Toll-Like Receptors / Q000378:metabolism*; D055815:Young Adult
D051194:Toll-Like Receptor 1; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4; D051199:Toll-Like Receptor 7; D051217:Toll-Like Receptor 9; D051193:Toll-Like Receptors