OBJECTIVETo investigate the changes of cytokines in induced sputum at different stages of silicosis patients.

METHODSA total of 200 workers from one of the Shandong Province gold mine were chosen as object of observation. Among which 40 patients at silicosis stage I and 40 patients at silicosis stage II were divided into silicosis observed object group, silicosis stage I group, silicosis stage II group, and another 80 workers exposed to silica dust without suffering from silicotic Clinical symptoms, however, were chosen as group of dust exposed, and 40 logistical workers without being exposed and history of silicosis's illness were chosen as control group. And ask their basic information by questionnaire. Then, spray-inhalation the induced sputum and apply the ELISA to assess the level of tumor necrosis factor (TNF), interleukin (IL), macrophage inflammatory protein-1 (MIP-1α), monocyte chemotactic factor-1 (MCP-1), metalloproteinases (MMP), transforming growth factor-β (TGF-β), platelet derived growth factor (PDGF) in induced sputum from subjects.

RESULTSThe level of TGF-β [(901.60 ± 30.09) ng/L] in the induced sputumof patients in silicosis stage I group is lower than that in the observed object group [(913.02 ± 20.51) ng/L], and the level of MMP-9 [(212.49 ± 5.97) ng/L], MCP-1 [(129.91 ± 4.30) ng/L] has various degrees of increase than that in control group, observed object group and dust exposed group. All the differences have statistical significances (P < 0.05). The level of TNF-α [(85.76 ± 3.78) ng/L] in the induced sputum of patients in silicosis stage I group reaches the maximum, there are significant differences comparing with that level in the silica dust exposure group and the control group, whose differences are statistically significant (P < 0.05). Compared with the control group, the level of MMP-2 (427.95 ± 23.64) in the induced sputum of patients in silicosis stage I group has increased, whose differences also have statically significant (P < 0.05). Compared with the control group, silica dust exposed group, the observation group of objects, the pneumosilicosis patients of IL-16 in induced sputum IL-16 (21.40 ± 9.24) decreased, the content of PDGF [(5.96 ± 0.51) ng/L], MMP-2 [(447.86 ± 27.10) ng/L], MMP-9 [(223.91 ± 12.28) ng/L], MCP-1 [(122.87 ± 6.08) ng/L] increased, the differences are statistically significant (P < 0.05).

CONCLUSIONAs silicosis biomarkers, TNF-alpha, TGF-beta, IL-16, PDGF, MMP-2, MMP-9 and MCP-1 have certain significance, further suggesting that early detection rate of patients with silicosis can be improved by employing the multiple indexes discriminate equation.