[Expression and characterization of human vascular endothelial growth factor receptor Flt-1 extracellular domain in...

By inserting VEGF receptor Flt-1(1-3 loop) cDNA into Pichia pastoris expression vector pPIC9K containing AOX1 promotor and the sequences of alpha secreting signal peptides, the expression plasmid pPIC9K/Flt-1(1-3) was constructed and transformed into GS115. The multi-copy insert transformants were selected and cultivated in flasks. After 4 days of 1% methanol induction, the expressed Flt-1(1-3) accumulated up to 30% of total proteins in supernatant. The expressed Flt-1(1-3) was further proved with good antigenicity and high specificity by ELISA and Western blot. They can bind to VEGF and inhibit HUVEC proliferation stimulated by VEGF.