Expression and characterization of glycoprotein gp35 of hepatitis C virus using recombinant vaccinia virus

Kohara, Michinori, Tsukiyama-Kohara, Kyoko, Maki, Noboru, Asano, Kaori, Yamaguchi, Kenjiro, Miki, Keizaburo, Tanaka, Satoshi, Hattori, Nobu, Matsuura, Yoshiharu, Saito, Izumu, Miyamura, Tatsuo, Nomoto, Akio

Abstract

^¹ Fundamental Research Laboratory, Corporate Research and Development Laboratory, Tonen Co. Nishi-Tsurugaoka, Ohi-machi, Iruma-gun, Saitama 354
^² Department of Microbiology, The Tokyo Metropolitan Institute of Medical Science
and The^³ Tokyo Metropolitan Komagome Hospital, Honkomagome, Bunkyo-ku, Tokyo 113
^⁴ Department of Veterinary Science
and^⁵ Department of Enteroviruses, National Institute of Health, Kamiosaki, Shinagawa-ku, Tokyo 141, Japan

Complementary DNA clones corresponding to one of the putative structural regions of the hepatitis C virus (HCV) genome were obtained from sera of non-A non-B hepatitis patients. The putative envelope gene was expressed by using a recombinant vaccinia virus carrying this region of the HCV genome. In cells infected with the recombinant vaccinia virus, a glycosylated protein with an M_r of about 35K (gp35) was specifically detected by convalescent sera from hepatitis C patients. The sera from rabbits immunized with this recombinant vaccinia virus reacted to the gp35 produced in insect cells and also to gp35 which was translated in vitro in the glycosylated and processed form. The gp35 was used to detect antibodies in sera of only 7 to 23% of HCV patients at various stages of HCV disease. These results suggest that the gp35 of HCV may not have high antigenicity in humans.