OBJECTIVETo study whether co-stimulatory molecule CD40 of alveolar macrophage (AM) participated in the occurrence and development of silicosis, and to explore the intervention of Yiqi Huoxue Decoction (YHD) in the fibrosis of silicosis patients.

METHODSTotally 46 silicosis inpatients and outpatients were recruited and randomly assigned to the Western treatment group (A) and the Chinese medicine (CM) treatment group (B), 23 in each group. Patients in Group A received routine symptomatic treatment such as anti-inflammation, phlegm resolving, anti-spasm, and asthma relief, and so on. Patients in Group B additionally took YHD, one dose daily for 14 successive days. Besides, another 18 patients with chronic cough and sense of laryngeal foreign bodies were recruited as the normal control group, who had no obvious lesion confirmed by bronchofi6roscope and clinical diagnosis of the lung. They were treated by symptomatic supporting treatment. The alveolar lavage fluid was collected from all patients and isolated, and AM cells were cultured. The level of CD40 mRNA was detected by RT-PCR. The expression of CD40 protein was detected by Western blot.

RESULTSCompared with the normal control group, expression levels of CD40 mRNA and CD40 protein significantly increased in Group A (P < 0.01). Compared with Group A, expression levels of CD40 mRNA and CD40 protein significantly decreased in Group B (P < 0.01).

CONCLUSIONSHighly expressed co-stimulatory molecule CD40 of AM might participate in pulmonary fibrosis. YHD could hinder its roles, inhibit the progression of fibrosis, thereby playing an interventional role of treatment.