Detection of HBsAg in a clone derived from the PLC/PRF/5 human hepatoma cell line

A total of 28 clones were established from the PLC/PRF/5 hepatoma cell line by a plating procedure. All clones were found to secrete HBsAg into the supernatant culture fluids. Of these, one clone (No. 23) free of detectable mycoplasma contamination and showing smooth epithelial morphology was selected for further study. Maximum accumulation of HBsAg occurred 9 days after sub-culture and intracellular antigen was detected by indirect immunofluorescence both in the cytoplasm and at the plasma membrane. Granules and perinuclear staining reactions were also observed in clone 23 cells and these findings are compared to the previously published properties of the parental PLC/PRF/5 cell line.