[The effect of serum high-density lipoprotein on the growth rate of human endothelial progenitor cells].

Objective: To study the effect of high-density lipoprotein (HDL) on the proliferation of endothelial progenitor cells (EPC) isolated from human umbilical cord blood; to further explore its effect on prevention and development of atherogenesis.
Methods: EPC isolated by density gradient centrifugation were cultured in a M200 medium. Immunofluorescence staining for CD133, CD34, KDR and Factor VIII were adopted respectively as the specific markers for identification. The effect of HDL on EPC proliferation was estimated on the 7th day of cell cultivation using MTT assay, confocal microscopy and fluorescence activated cell sorting.
Results: HDL, when incubated with EPC, was able to promote remarkably the proliferation rate of EPC, dose- and time-dependent. HDL participated in the transcriptional regulation of cell cycle by affecting the regulatory proteins such as cyclin D1.
Conclusions: A subtype of progenitor cells was isolated from human cord blood with a potential of differentiating into mature endothelial cells (known as endothelial progenitor cells). HDL plays an important role on EPC fluorescence activated cell sorting differentiation and proliferation. Further studies are required to identify the signal pathway and the molecular mechanism of HDL effect on EPC proliferation.