PURIFICATION, CHARACTERIZATION AND IMMUNOGENICITY OF RECOMBINANT VARICELLA-ZOSTER VIRUS GLYCOPROTEIN GE SECRETED BY CHINESE-HAMSTER OVARY CELLS

The gene of the varicella-zoster virus (VZV) glycoprotein gE, engineer ed to code for a truncated molecule lacking the anchor and carboxy-ter minal tail domains, was transfected into Chinese hamster ovary (CHO) c ells via the pEE14 mammalian expression vector. One recombinant cell l ine, CHO-gE-2-9, secreted high levels of truncated gE into the culture medium. The product was purified to near homogeneity by a combination of anion exchange, hydrophobic and metal-chelate chromatographies. Pu rified recombinant gE showed the expected amino-terminal sequence and its glycosylation pattern proved similar to that of the natural produc t. When injected into mice, using either Freund's or alum as adjuvant, the native truncated gE induced complement-dependent neutralizing ant ibodies. In contrast, when the molecule was first: denatured, it lost immunogenicity with alum. These data show that the recombinant gE, alt hough truncated, could potentially be included in a subunit vaccine ag ainst VZV infection.