AimTo investigate effects of advanced glycation end products (AGE) modified albumin (AGE-albumin) on functions of late endothelial progenitor cell (EPC) derived from human umbilical cord blood and its mechanisms.MethodsMononuclear cells from human umbilical cord blood were cultured by using EGM-2-MV (Clonetics).Expression of CD45, CD146, and CD105 were detected by fluorescence-activated cell sorter analysis (FACS), vWF was detected by immunocytochemistry.Uptake of acetylated low density lipoprotein (ac-LDL) and binding to Ulex European Agglatinin (UEA-1) were used for fluorescent labeling of EPC.Late EPC were incubated with different concentrations of AGE-albumin which were similar to the diabetic serum for 24 h.MTT was used for EPC proliferation assay.To measure the apoptosis, Annexin V＋/PI－ cells were detected by FACS analysis.Boyden chamber assay was used to detect the migration by vascular endothelial growth factor (VEGF).Tube formation on ECMatrix-gel was performed to assess the capacity for vasculogenesis.The mRNA and protein expression of AGE receptor (RAGE) were evaluated by reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blotting, respectively.ResultsThere were two types of cells appeared in the culture system.After 3 to 5 d, attached cells appeared and appeared to be clusters.Their number increased for 2 weeks.Thereafter, they did not replicate in vitro and gradually disappeared.We observed another population of cells with different morphology and growth pattern.These appeared in 10 to 15 d after plating, with