OBJECTIVETo investigate the activation of Toll like receptor 4 (TLR4) on passively sensitized human airway smooth muscle cells (HASMCs) proliferation and the synthesis and secretion function.

METHODSThrough the cultivation of primary HASMCs, we studied TLR4 expression on cell surface, cell proliferation and transformation of parturient factor-beta1 (TGF-beta1) in asthma under the condition of synthesis and secretion level by passively sensitized HASMCs with asthma serum.

RESULTSCompared with the control group, in passive sensitized group and TNF-alpha group TLR4 expression were significantly increased (P < 0.01), significantly enhanced proliferation (P < 0.01), total protein concentration, IgE secretion and TGF-beta1 were significantly higher (P < 0.01); and all the above parameters were increased more significantly in TNF group compared with those in the target effect of passively group; and those parameters were significantly reduced in anti-TLR4 antibody group compared with those in the target effect both of passively sensitized group and TNF-alpha group.

CONCLUSIONTLR4 on passively sensitized HASMCs activated can induce the excessive proliferation of HASMCs and a large number of synthesis and secretion of TGF-beta1, resulting in changing airway micro-environment, which involved in airway remodeling in asthma.