Abstract：Objective: To establish and identify the cysteine-rich 61 (CYR61/CCN1) gene knockout mice via Cre-LoxP conditional gene knockout technology, and to build animal model for researchers to explore the role and mechanism of CCN1 gene in lung inflammation. Methods: The introduced CCN1flox/flox mice and the mice that express pulmonary epithelial cell-specific Cre recombinase were bred and authenticated separately. After successful identification, two kinds of mice were hybridized. The off-spring mice with Cre+/-CCN1flox/flox genotyping were the objective mice. Results: Cre+/-CCN1flox/flox mice were successfully bred and identified. An intraperitoneal injection of tamoxifen was administered to stimulate the experiment group (Cre+/-CCN1flox/flox) and the control group (Cre-/-CCN1flox/flox). RT-PCR, immunofluorescence, immunohistochemical and Western-blot were applied to detect mRNA and protein expression of CCN1 in lung tissue. There was a significant decrease of CCN1 mRNA and protein expression in the lung tissues of experiment group compared with the control group. Conclusion: Based on the Cre-LoxP conditional gene knockout technology, we succeed in building a group of lung epithelial cell-specific CCN1 gene knockout mice which can stably go down to the future generation. This kind of mice would supply a technical basis for animal models in further researches of the regulation and mechanism of CCN1 gene in the inflammation of lung tissues.
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