A model of lung eosinophilia based on the repeated exposure of mice to aerosolized OVA has been used to identify C-C chemokine genes expressed at stages of massive eosinophil infiltration. We describe the identification and cloning of a cDNA that encodes a mouse C-C chemokine with 68% amino acid identity to guinea pig Eotaxin. The recombinant protein encoded by this gene displays potent and specific chemotactic activity for eosinophils, both in vivo and in vitro. Its mRNA levels parallel the kinetics of eosinophil accumulation in the lung during the experimentally induced eosinophilia and it is mainly produced by type I alveolar epithelial cells. The mRNA expression of mouse Eotaxin is not restricted to Th2 T cells in vitro and is independent of the development of a Th2-type response during N. brasiliensis infection, in vivo.

SummaryWe have cloned a novel mouse CC chemokine cDNA from the lung during an allergic inflammatory reaction. The protein encoded by this cDNA is chemotactic for eosinophils, monocytes, and lymphocytes in vitro and in vivo. Based on its similarities in sequence and function with other CC chemokines, we have named it mouse monocyte chemotactic protein-5 (mMCP-5). Under noninflammatory conditions, expression of mMCP-5 in the lymph nodes and thymus is constitutive and is generally restricted to stromal cells. Neutralization ofmMCP-5 protein with specific antibodies during an allergic inflammatory reaction in vivo resulted in a reduction in the number of eosinophils that accumulated in the lung. Moreover, mMCP-5 mtkNA expression in vivo is regulated differently from that of other major CC chemokines in the lung during the allergic reaction, including Eotaxin. The presence oflymphocytes is essential for expression of mMCP-5 by alveolar macrophages and smooth muscle cells in the lung, and the induction of mMCP-5 RNA occurs earlier than that of the eosinophil chemokine Eotaxin during allergic inflammation. In contrast to Eotaxin, mR.NA for mMCP-5 can be produced by mast cells. From these results, we postulate that mMCP-5 plays a pivotal role during the early stages of allergic lung inflammation.

This study was based on network pharmacology and molecular docking combined with experiments in vitro to explore the potential anti-inflammatory mechanism of Portulaca oleracea L. flavone (POL-F). First, the core targets of inflammation in purslane were screened through various databases and software, GO and KEGG analysis and molecular docking were performed. Then, mouse macrophage RAW264.7 was selected as the study object, and the safe experimental concentration of POL-F was confirmed by CCK-8 assay. The cells were divided into a control group, an LPS inflammatory cell model group, and an LPS inflammatory cell model group treated with different concentrations of POL-F. The secretion of NO in each group was detected by the Griess method. The expressions of IL-1β, IL-7, and TNF-α in the supernatant were detected by ELISA. The regulatory effects of POL-F on p-PI3K and PAKT signaling pathway proteins in cells of each group were detected by Western blot. The results showed that Pol-F treated with 100, 200, and 400 μg/ mL had no toxic effect on cells. The three concentrations of POL-F showed inhibitory effect on NO secretion of inflammatory cells, and the inhibitory activity was the best at 400 μg/ml. The expression of p-PI3K and PAKT protein was also inhibited after POL-F treatment. In conclusion, POL-F has a significant inhibitory effect on inflammatory response in vitro.