Morphological observation of GFP gene-modified mesenchymal stem cells cultured with PLGA substrate / 中国综合临床

ABSTRACT

Objective To investigate the feasibility of using PLGA loaded with SD rats' mesenchymal stem cells(rMSCs) transfected with green fluorescent protein (GFP) gene as scaffolds for combinations of molecular, cellular, and tissue-level treatments of spinal cord tissue engineering. Methods rMSCs infected with lentiviral vectors (lv-GFP) were seeded onto PLGA at 8000 cell/cm2, rMSCs-GFP grown under similar conditions on tissue culture plastic as control. The morphology of rMSC-GFP was examined by fluorescence microscopic. The activity of MSCs was detected by MTT assay everyday. Cell cycle analysis was performed after a 3-day culture on PLGA using flow cytometry. The rMSCs-GFP seeded on PLGA was identified by FITC-anti CD34,CD90 and PE-anti CD44, CD106,CD45,CDllb at the third day. Results Fluorescence microscopic examination revealed adherence of the cells to the PLGA surface within 24 h of initial plating. After 3 days, GFP cells were spindle shaped. The difference disappeared at 7 days when cells under both conditions had become confluent Cells proliferated at the same rate on the PLGA surface compared to tissue culture plastic. And cell's cycle was unaffected by the transduction process and seeded on PLGA. Cells maintained their stem cell phenotype as judged by expression of CD90, CD44, CD106 markers,and absence of the hematopoietic marker CD45, CD34. This demonstrated that the transduction and the PLGA surface were not adversely affecting the cells. Conclusions MSCs are a good candidate for spinal cord tissue engineering. Cells continued to express green fluorescent protein(GFP)on a long-term basis,and are compatible with polymer surfaces. Morphology,viability,and growth kinetics were maintained when cells were grown on a poly-lactic-co-glycolic acid(PLGA)polymer scaffold. Therefore,they could make further efforts for combinations of molecular, cellular,and tissue-level treatments of spinal cord tissue engineering.