Abstract: To provide seed cells for breeding genetically modified beef cattle and to enrich multi-differentiation potential of the bovine BMSC, immunofluorescence staining and molecular biology technology were used to explore the possibility of BMSC differentiating into mammary gland-like epithelial cells in vitro in the presence of the epidermal growth factor (EGF), insulin, prolactin, progesterone and so on. Purified and stable P4, P8 and P12 generation bovine BMSC were utilized to induce in vitro in medium with different cytokines and different concentrations. We used immunofluorescence and RT-PCR to observate and identify the cells after inducing. The results suggested that some BMSC changed from Spindle-like cells into polygon-like cells after induction;meanwhile they were clearly showed fluorescence by cytokeratin 18 staining. The bovine P4 generation BMSC remarkably differentiated under the action of induction medium Ⅱ. RT-PCR results demonstrated that cells after induction clearly expressed cytokeratin 19 gene, β-casein gene and αs1-casein gene. Consequently, BMSC can differentiate into mammary gland-like epithelial cells by using multi-factor to induce in vitro and the induction medium Ⅱshow good effects.

Key words: Black cattle; bone marrow mesenchymal stem cells; EGF; nsulin; prolactin; progesterone; mammary gland-like epithelial cells