[Correlation analysis between cytokines levels in serum and bronchoalveolar lavage fluid, blood T cell subsets and pneumoconiosis severity].

Objective To analyze the correlation between the pneumoconiosis severity and the cytokines levels in serum and bronchoalveolar lavage fluid (BALF) or blood T cell subsets.Methods The subjects were divided into five groups:control group (6 cases),group exposed to dusts (6 cases) and 3 pneumoconiosis groups (36 in stage I,12 in stage Ⅱ and 10 in stage Ⅲ).ELISA was used to detect IL-6,sIL-2R and TNF-α levels in serum and BALF.The subsets of blood T cells were classified by flow cytometer.Results As compared with control group and group exposed to dusts,the levels of serum IL-6 and sIL-2R in patients with Ⅱ or Ⅲ stages significandy increased,which were positively correlated with pneumoconiosis stages (r1=0.74,r2=0.81,P＜0.05).The level of serum TNF-α significantly decreased in patients with Ⅲ stages,as compared with control group and group exposed to dusts.There was a negative correlation between serum TNF-α level and pneumoconiosis severity (r=-0.58,P＜0.05 ).There was a positive correlation between the levels of IL-6、sIL-2R and TNF-o in BALF and the levels of IL-6 、sIL-2R and TNF-α in serum (r1=0.77,r2=0.96 and r3=0.88,P＜0.05).The proportion of CD4+T cells and the ratio of CD4+/CD8+ deceased dramatically in patients with Ⅱ and Ⅲ stages.But there was no correlation between these values and disease severity.Conclusion The immune function in Th cell was inhibited.The levels of IL-6,sIL-2R and TNF-α in serum and BALF were associated with the severity of pneumoconiosis. Key words: Pneumoconiosis;  Interleukin-6;  Tumor necrosis factor α, T-lymphocyte subsets