Hepatitis B surface antigen produced by a human hepatoma cell line

Abstract

Summary.-Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46°' of the patients.Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (Cl) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation.

Stable Expression of the Hepatitis B Virus Surface Antigen Containing Pre-S2 Protein in Mouse Cells Using a Bovine Papillomavirus Vector

“…The amount of HBsAg produced and released into the medium was estimated to be 1 to 4~tg/ml/day (18 gg/107 cells/day). The production rate of HBsAg particles from MS 128 cells was 20 to 30 times higher than that of the well-known human hepatoma cell line PLC/PRF/5 (Macnab et al, 1976). Efficient production of HBsAg in mammalian cells (6 to 12 p.g/10 v cells/day) has been reported previously (Hsiung et al, 1984;Michel et al, 1984;Wang et al, 1983); the level of HBsAg production for MS128 cells was equivalent to, or higher than, those reported.…”

Hepatitis-B surface antigen in tumour tissue and non-tumorous liver in black patients with hepatocellular carcinoma

“…The latter conclusion is supported by an HCC growing in tissue culture which is producing HBsAg (Macnab et al, 1976). However, these findings do not answer the key question whether the virus is the cause or the result of the tumour.…”

Expression of Hepatitis B Virus Core Antigen Gene Is Induced in Human Hepatoma Cells by Their Growth in Nude Mice

“…One of them, the human hepatoma cell line PLC/PRF/5 (Macnab et al, 1976), contains HBV DNA specific for the surface antigen (HBsAg) and the core antigen (HBcAg) both extrachromosomally (Zaslavsky et al, 1980;Marquardt et al, 1982) and integrated into chromosomes (Edman et al, 1980;Miller & Robinson, 1983). HBsAg is produced by the cells and functionally active genes were found among the HBV DNA copies integrated into the chromosomes (Dejean et al, 1983;Koshy et al, 1983).…”