Two step culture for production of recombinant herpes simplex virus type 2 glycoprotein D in immobilized <i>Spodoptera frugiperda</i> cells

Abstract

Herpes simplex virus type 2 (HSV-2) was the major cause of genital herpes in humans. The HSV-2 glycoprotein D (gD2) had been proved to be a potentially effective vaccine for treatment of genital herpes. The present study was to develop a two step culture to express the recombinant gD2 protein using the immobilized Spodoptera frugiperda (Sf9) cells. The first step, Sf9 cells were cultured and harvested in eutrophic medium containing 10% fetal bovine serum. The second step, Sf9 cells were immobilized using silk fibroin hydrogel and cultured in a stirred-tank bioreactor after infection by recombinant baculovirus expressing the full length gD2 gene. The data shows that the maximum yield of recombinant gD2 protein reached the concentration of 135 mg/L. The results reveal that the immobilized cells and two step culture could extend the expression period and significantly raise the production of the recombinant protein.

Key words: Spodoptera frugiperda cells, baculovirus, immobilization, glycoprotein D, silk fibroin hydrogel.