KDR and FLT4 in HDMECs, HUVECs and leukemia cell lines. KDR and FLT4 mRNA expression levels were determined by quantitative real-time PCR and indicated underneath the cell line name. TBP expression was used as endogenous control and cell lines CMK (KDR) and HEL (FLT4) were used for normalization. KDR protein expression levels--determined by Western blot analysis--are higher in HDMECs and HUVECs than in positive cell lines (note 1:10 lysate dilution in primary cells). FLT4 protein expression is higher in HDMECs than in HUVECs (note 1:10 lysate dilution in HDMECs) and in positive cell lines. Protein expression corresponds to mRNA expression pattern.