Recombination and purification of IL-23 gene and its effect on immune response to airway inflammation in asthma during pregnancy

Abstract

Aim To investigate the immune regulation of IL-23 fusion gene and the correlation between its biological function and the airway inflammation in asthma during pregnancy. Methods The eukaryotic expression plasmid,which was constructed to express the IL-23p40 + p19 double subunit,was used to transform E.coilBL21 bacteria,and the expression products,which were induced by IPTG,were purified and detected by SDS-PAGE and Western blot. The transfection,mediated by recombinant protein,was identified by fluorescence microscopy and plasmid's Western blot,while DNA binding activity of nuclear proteins was measured by gel electrophoresis. To evaluate the impact of foreign protein in vivo,mouse serum inflammatory cytokines levels and inflammation injury in lung tissue were measured by ELISA method and HE staining. The CD4+T cell subset's proportion of mononuclear cells in peripheral blood was verified by flow cytometry. Results The results showed that soluble exogenous recombinant protein,which was obtained successfully,had the ability of trans-membrane transport and could effectively mediate EGFP into the target cells. Its stable expression and transcriptional activity were higher than those of simple plasmid's effect. The specific binding between GST/pCEP4-IL-23 and plasmid DNA formed macromolecular complexes,which could decrease the mobility of gel. The combined effect with LPS significantly increased the IL-17A levels in serum(P 0. 05) and the inflammation reaction in lung tissue of sensitized mice. Mean while,it also reduced the IFN-γ,Foxp3 level in serum,promoted the activation of IL-4 and IL-17A,and then increased the ratio of Th2/Th1and Th17/Treg(P 0. 05). Conclusions The recombinant IL-23 protein is pathogenic,and it adjusts the inflammation of asthma in pregnancy. The immune imbalance of CD4+T subsets affects the immune tolerance of pregnant body and the development of asthma during pregnancy.