The Construction of Mesenchymal Stem Cells Carrying Angiopoietin 1 and Its Application in Lung Injury

Objective To determine if mesenchymal stem cells (MSCs) could be reconstructed as a vehicle for angiopoietin-1 (Ang1) gene therapy in lung injury. Methods MSCs were obtained from adult male inbred mice and cultured to passage four. The cells were identified by fluorescence-activated cell sorting (FACS) analysis and cell differentiation detection. Lentiviral vectors contained GFP and Ang1 gene were conducted in 293T cells through three plasmids co-transfection method. Then MSCs were transduced with Ang1 gene efficiently through lentiviral vectors. The mRNA expression of Ang1 in MSCs was detected by RT-PCR before and after transfection. Also fluorescence from MSCs was detected by fluorescence microscope every day after transfection. Two hours after LPS inhalation,mice were infused via jugular vein with normal saline (NS group),lentiviral vector carrying Ang1 (Ang1 group),lentiviral vector carrying GFP(MSCs group),and lentiviral vector carrying Ang1/GFP (MSCs-Ang1 group),respectively. Kaplan-Meier survival analysis was performed to compare the effects of MSCs-Ang1 on survival. And ectogenic MSCs origined lung cells were investigated in receipt mice. Results After passaged and purification,MSCs were confirmed to have the potential of differentiation. The lentiviral vectors carrying Ang1 and GFP were also identified. After transfection,the mRNA expression of Ang1 in MSCs was enhanced. Through the fluorescence microscope,MSCs get the most green fluorescence expression five days after the transfection when MOI was 20. Kaplan-Meier survival analysis showed that MSCs-Ang1 infusion had improved survival rates of lung injury rats compared with the control,but it did not reach statistical significance (P=0.066). Cells expressing GFP in lung tissues can be observed after MSCs were transplanted in vivo. Conclusions MSCs expressing Ang1 high can be constructed through lentiviral vector transfer,and MSCs-origined cells can be detected in receipt lungs after transplantation. So MSCs may serve as a vehicle for gene therapy in lung injury.