This study was aimed to investigate the transfection efficacy of recombinant adeno-associated virus 2/1 (rAAV2/1) on bone marrow mesenchymal stem cells (BMMSCs) at different multiplicities of infection (MOI) and time, and effect of transfection on growth of rat BMMSCs. The rat BMMSCs cultured in vitro were transfected by using rAAV2/1 with enhanced green fluorescent protein (rAAV2/1-EGFP) at MOI of 1 x 10(4), 1 x 10(5) and 1 x 10(6); the EGFP expression was observed by fluorescent microscopy at 3, 7 and 14 days. The viability, proliferation multiple, differentiation ability of daughter cells were detected for evaluating the effect of rAAV2/1 on survival, proliferation and differentiation of BMMSCs and the fluorescence index (FI) were determined by flow cytometry. The results indicated that after transfection with rAAV2/1 for 24 hours the green fluorescence in BMMSCs were observed, but also the fluorescence gradually was enhanced along with prolonging of time, and reached to steady level after 7 days; the viability, proliferation multiple, differentiation ability of BMMSCs transfected by rAAV2/1-EGFP at different MOI showed no significant changes at 3,7 and 14 days (p > 0.05), meanwhile at same MOI the proliferation multiple obviously increased in comparison between 7 day vs 3 day and 14 days vs 7 days (p < 0.01). The flow cytometric detection showed that the transfection efficacy of rAAV2/1-EGFP on BMMSCs and FI increased significantly as the multiplicity of infection and culture time increased (p < 0.05). It is concluded that rAAV2/1-EGFP is able to transfect into BMMSCs effectively, but the transfection efficiency and fluorescence index increase significantly along with increase of multiplicity of infection and culture time. rAAV2/1-EGFP do not affect viability, proliferation multiple and differentiation ability of BMMSCs. rAAV2/1 is a kind of active vector for gene transfer to reform BMMSCs.
Animals ; Bone Marrow Cells ; cytology ; Dependovirus ; genetics ; Genetic Vectors ; Male ; Mesenchymal Stromal Cells ; cytology ; Rats ; Rats, Sprague-Dawley ; Transfection

Objective The aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells ( MSCs) with tumor cells can promote tumor angiogensis.Methods Human glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene.Bone marrow mesenchymal stem cells ( MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression.Then the two kinds of cells were co-cultured in vitro.At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors.The co-cultured cells, GFP/RFP double positive ( yellow ) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope.Results After five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105.CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas.When MSCs were co -cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7%of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells.Conclu sion Cell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.

Objective The aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells ( MSCs) with tumor cells can promote tumor angiogensis.Methods Human glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene.Bone marrow mesenchymal stem cells ( MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression.Then the two kinds of cells were co-cultured in vitro.At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors.The co-cultured cells, GFP/RFP double positive ( yellow ) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope.Results After five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105.CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas.When MSCs were co -cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7%of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells.Conclu sion Cell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.