RESULTS: ①Subjects (n=58) had divided into simple snoring group (n=10), mild OSAHS group (n=9), moderate OSAHS group (n=4), and severe OSAHS group (n=35), according to polysomnography. ②In OSAHS group and severe OSAHS group, the levels of sTLR2 in plasma were down-regulated. Before sleep VS. after sleep (ng/ml) were 1.041 (0.609,1.997) ng/ml VS. 0.610 (0.580, 0.970) ng/ml, P=0.003; 1.419±1.225 ng/ml VS. 0.620 (0.580, 1.350) ng/ml, P=0.015, respectively. ③In OSAHS group and severe OSAHS group, the surface expressions of TLR2 on neutrophils were up-regulated. Before sleep VS. after sleep (%) were 27.43±14.32 VS 36.10±17.43, P=0.000; 29.83±13.27 VS 39.49±16.75, P=0.001, respectively. ④Linear regression analysis revealed AHI was associated with the levels of sTLR2 in severe OSAHS group before sleep (r=−0.383, P=0.023). The positive correlation was shown between AHI and D-value of sTLR2 through the sleep in severe OSAHS group, with significant statistic (r=0.349, P=0.040).