ABSTRACT
To observe the expression changes of interleukin-11 (IL-11) and its receptor in mice with pulmonary fibrosis. Methods: C57BL/6 mice were randomly divided into a control group and a bleomycin (BLM) group (6 mice per group). BLM was injected into mice to induce idiopathic pulmonary fibrosis, while 50 μL PBS was injected into the control rats. The lung tissue was collected 21 d later. HE staining was used to observe morphological changes in lung tissue. Real-time PCR was used to detect IL-11 and its receptor gene expression. Western blot and immunohistochemical staining were used to detect IL-11 receptor expression. ELISA was used to detect the content of serum IL-11 in mice. In addition, the gene and protein expression of IL-11 receptor in mouse fibroblasts were detected by real-time PCR and Western blot, respectively. Results: HE staining showed a significant change in pulmonary fibrosis in mice 21 d after BLM injection. The IL-11 mRNA expression in lung and IL-11 level in serum were up-regulated. The gene and protein expression of IL-11 receptor in mice with pulmonary fibrosis were significantly increased. The results from the cell experiments showed that the gene and protein expression of IL-11 receptor in mouse fibroblasts were significantly increased by TGF-β1. Conclusion: The expression of IL-11 and its receptor are up-regulated in mice with pulmonary fibrosis induced by BLM, which might be an important mechanism for the development of pulmonary fibrosis.