Production of functional hepatocyte growth factor (HGF) in insect cells infected with an HGF-recombinant baculovirus in a serum-free medium.
Three insect cell lines, SL-7B cells derived from Spodoptera litura, Sf9, and High Five (Hi-5) cells, were used for the production of pro-hepatocyte growth factor (pro-HGF). Cells were cultured and then infected with a recombinant HGF-containing baculovirus in a serum-free medium. In SL-7B cells, pro-HGF is synthesized and excreted from the cells and late in infection is converted to a heterodimeric form of HGF even when the cells are grown in serum free medium. Conversion of a single-chain form of HGF (pro-HGF) into an HGF heterodimer was unexpected, as pro-HGF is normally cleaved by a serum protease called HGF activator. The proliferation activity of heparin-affinity-purified HGF from serum-free culture supernatant of SL-7B cells is comparable to that obtained from HGF converted by serum proteases, suggesting that SL-7B cells produce a functionally analogous protease to correctly process pro-HGF. This work reports, for the first time, on the feasibility of properly processing pro-HGF to form functional HGF by proteases from invertebrate cells in serum-free media. Avoiding the supplementation of sera provides the advantages of a low production cost, zero contamination of infectious agents from sera, and simple downstream product purification. Experimental results further demonstrate that the conversion of pro-HGF by insect cells is cell-line-dependent, because proteases in Hi-5 or Sf9 cells could not process pro-HGF as efficiently and properly as those in SL-7B cells.
Wang
M Y
MY
Graduate Institute of Agricultural Biotechnology, National Chung Hsing University, Taichung, Taiwan 40227 ROC. mywang@gragon.nchu.edu.tw
Yang
Y H
YH
Lee
H S
HS
Lai
S Y
SY
D000818:Animals; D016367:Baculoviridae / Q000235:genetics*; D001709:Biotechnology / Q000379:methods; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002846:Chromatography, Affinity; D016895:Culture Media, Serum-Free; D005822:Genetic Vectors; D006493:Heparin / Q000378:metabolism; D017228:Hepatocyte Growth Factor / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D015202:Protein Engineering / Q000379:methods*; D011498:Protein Precursors / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D018411:Spodoptera / Q000166:cytology* / Q000235:genetics / Q000821:virology
D016895:Culture Media, Serum-Free; D011498:Protein Precursors; D011994:Recombinant Proteins; D017228:Hepatocyte Growth Factor; D006493:Heparin