Construction of eukaryotic expres sion vector for α-Fodrin siRNA and evaluation of its therapeutic effects on NOD mice / 中华风湿病学杂志

ABSTRACT

Objective To construct two vectors of small interfering RNA (siRNA) expressing α-Fodrin and investigate its therapeutic effects on mice model with primary Sj(o)gren's syndrome (non-obese diabetic mice,NOD mice).Methods Sixteen 8-week-old NOD mice were randomly divided into four groupsthe control group,the vector group,the α-Fodrin-siRNA1 group and α-Fodrin-siRNA2 group,4 mice in each group.Four template DNA of α-Fodrin siRNA were chemically synthesized and annealed to two double stranded (dsDNA),then digested by BamH Ⅰ and Hind Ⅲ.The digested double strands oligos were inserted into the downstream of U6 promoter of linearized pGFP-V-RS vector.Recombinant were confirmed by restrictive enzyme digestion and sequencing.Then the vectors were injected throughtail veil once a week,two times in total,while mice in the control group were injected with the same dose of phosphate buffer saline (PBS)and the vector group were injected with the same dose of vector vehicle.pGFP-V-RS was labeled by green fluorescent protein(GFP) and lacriminal glands underwent pathological examination.In addition,the expression of α-Fodrin mRNA in lung were detected by reverse transcription-polymerase chain reaction (RTPCR),and α-Fodrin protein in lacriminal glands and lung were detected by immuno-histochemistry.Serum interferon (IFN-γ),interleukin-17 (IL-17) concentrations in each group were detected by enzyme linked immunosorbent assay (ELISA) in order to observe changes in cytokine levels.At the same time,the pathological changes of the lacriminal glands and organs with hematoxylin-eosin (HE) staining were observed.The repeat ANOVA was used for statistical analysis.Results ① We constructed two siRNA eukaryotic expression vector successfully; ② α-Fodrin-siRNA could target to the lacriminal glands.③ Compared with the control group and vector vehicle group,the expression of α-Fodrin mRNA and protein were significantly decreased in the treatment groups.④ Compared with the control group [(11.73±2.73) pg/ml] and vector vehicle group [(15.40±1.99) pg/ml],serum IL-17 levels in the treatment groups were [α-Fodrin-siRNA 1 group (4.38±1.02) pg/ml; α-Fodrin-siRNA 2 group (4.55±0.06) pg/ml] significantly decreased (P＜0.05),but IFN-γ levels in the αt-Fodrin-siRNA group were not decreased significantly (P＞0.05).⑤ Compared with the control group and vector vehicle group,lymphocyte infiltration of lacriminal gland and inflammatory cell infiltration of alveolar and interstitial were significantly reduced in α-Fodrin-siRNA groups.Conclusion Specific α-Fodrin siRNA can inhibit the inflammation,and suppress the inflammatory infiltration of lacriminal glands and lung in mice with primary Sj(o)gren's syndrome.So the constructed vectors may slow the progression of pSS.