Inhibitory effect of miR-20b on airway inflammation in asthmatic mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect of miR-20b in inhibiting airway inflammation in a mouse model of asthma.</p><p><b>METHODS</b>Female BALB/c mouse models of asthma, established by sensitizing and challenging the mice with a mixture of ovalbumin and aluminum hydroxide, were subjected to intranasal instillation of 20 µg miR-20b mimics or a miR-20b scramble every 3 days. On day 49, bronchoalveolar lavage fluid (BALF) was collected from the mice to examine the counts of total cells and different cell populations; HE staining was used to observe the pathological changes of the lung tissue, and the concentration of vascular endothelial growth factor (VEGF) in BALF was detected by ELISA.</p><p><b>RESULTS</b>Treatment of the asthmatic mice with miR-20b mimics decreased not only the counts of the total leukocytes, neutrophils and eosinophils in the BALF but also mucus secretion in the airway and inflammatory cell infiltration around the bronchus, and lessened thickening of the airway mucosa. Instillation with miR-20b mimics significantly reduced the concentration of VEGF in BALF from 28.55±3.42 pg/mL in the asthma model group to 18.19±3.67 pg/mL (P<0.01).</p><p><b>CONCLUSION</b>MiR-20b can inhibit airway inflammation in asthmatic mice possibly by reducing the expression of VEGF.</p>

Expression of Recombinant sPDGFR?-Fc in CHO and Its Anti-proliferation Analysis / 中国生物工程杂志

Orjective:To obtain recombinant CHO-K1 with expressing sPDGFR? and to identify the biological activities of sPDGFR? secreted in non-serum medium.Methods:Recombinant human sPDGFR? expression vector pIRES-Neo3-sPDGFR?-Fc was constructed and then transfected into CHO-K1 cells by using LipofectamineTM 2000.After screened with G418 in 8 weeks,some monoclone cells were selected randomly to amplify in 96-well-plate to 24-well-plates,and then to identify positive cell clones by RT-PCR.Furthermore,the candidate cell clones were test by Real-Time PCR and Western blot assays.Finally,anti-proliferation activities of the expressed sPDGFR? were analyzed by MTT.Results:sPDGFR?-Fc was cloned into pIRES-Neo3 correctly.The sPDGFR?-Fc expression level in recombinant CHO-K1 cell clones were concordant in between Realtime PCR and Western blot assay.sPDGFR?-Fc obtained from cultured non-serum medium of positive CHO-K1 could significantly inhibit proliferation of vascular endothelial cell.Conclusion:Successed to select recombinant CHO-K1 cell lines with high expressed sPDGFR?-Fc.The sPDGFR?-Fc can inhibit the cell proliferation significantly and it means sPDGFR?-Fc might be a new anti-cancer drug in the future.