Abstract: Objective To explore the effects of serum concentration on the culture of Lymphatic endothelial cells（LECs） and determine an optimal serum concentration on the culture of LECs.Methods LECs were isolated and identified by immunomagnetic beads sorting method,then divided into 5 experimental groups and cultured with 5 different serum concentrations of EGM-2 respectively（0%,2.5%,5%,7.5% and 10%）.The proliferation and function of the LECs were examined and compared by immuno-fluoresence staining,RT-PCR,flow cytometry,matrigel assay and Dil-Ac-LDL uptake experiment.Results The cells obtained by immunomagnetic beads sorting method demonstrated the specific marks and functions of LECs.There were no significant differences on Dil-Ac-LDL uptake of LECs in each group.The tube-like structure was not found in the 0% serum concentration group.It is revealed that the lymphatic vessels formation and proliferation were the highest in 7.5% serum concentration group.Conclusion The serum plays an important role in LECs culture,especially in cell proliferation and function.The optimal serum concentration is 7.5% serum concentration,which is conducive to the proliferation and function of LECs.

Key words: Serum, Lymphatic endothelial cells, Culture