Expression of Adenovirus-mediated Human Clotting Factor IX Gene in Mouse Adipose-derived Stem Cells

Abstract

To investigate the adenovirus-mediated expression of human clotting factor IX (hFIX) gene in mouse adipose-derived stem cells(ADSC). The mouse ADSC were isolated and cultured in vitro, the morphology of cells was observed and its growth viability was detected by using CCK-8. Cell surface markers CD29,CD90,CD45 were identified by flow cytometry, and its diferentiation ability was identified by adipogenic and osteogenic induction. Morphological changes was observed and the growth curve should be drawn after transfecting ADSC with adenovirus containing hFIX gene. The expression of hFIX gene was detected by RT-PCR. The expression of hFIX protein in ADSC or in culture supernatant was detected by Western blot. hFIX protein in the supernatant was measured by ELISA, and the clotting factor activity of hFIX in culture supernatant was measured by one-stage method. The in vitro cultured mouse ADSC displayed microspherical shape and strong refractive property. Anchoring growth was lasted for 4-6 hours after planting into culture flask. After cultured for 72 hours, the cells showed long spindle-shaped fibrous and swirling arrangement. The overall growth trend of the third generation ADSC cultured in vitro was S-shaped. The formation of lipid droplets could be observed in the induced cells with Oil red O staining by inverted microscope. After alizarin red staining, the orange-red calcified bone nodes were observed in the induced cells under inverted phase contrast microscope. CD29 (99.91%) and CD90 (99.02%) highly expressed in the third generation of ADSC, but CD45 (0.94%) almost not expressed. RT-PCR showed the hFIX gene could expressed in mouse ADSC. Western blot showed that hFIX protein expressed in both ADSC and culture supernatant. FIX:Ag in cell supernatant was 21.33±3.93 ng/(106 cells.24 h) on the first day, 12.63±0.86 ng/(106 cells.24 h) on the third day and 12.63±2.36 ng/(106 cells.24 h) on the ninth day. FIX:C in culture supernatant was 8.5%. Adenovirus-carried hFIX gene can effectively transfect ADSC. ADSC modified by hFIX gene can secrete hFIX protein with coagulation activity.