Stable HBV surface antigen expression by Vero cell clones after transfection

Area of Science:

• Biotechnology
• Virology
• Cell Biology

Background:

• Hepatitis B virus (HBV) poses a significant global health challenge.
• Developing stable expression systems for HBV antigens is crucial for vaccine and therapeutic research.

Purpose of the Study:

• To establish a stable cell line for hepatitis B surface antigen (HBsAg) expression in mammalian cells.
• To characterize the expression profile and biological properties of HBsAg-producing cells.

Main Methods:

• Vero cells were transfected with plasmids encoding HBsAg and a selectable marker (aminoglycoside 3' phosphotransferase - APH3').
• G418-resistant clones were selected and screened for stable HBsAg expression.
• Characterization included expression levels, stability over time, tumorigenicity in nude mice, and immunogenicity of excreted HBsAg.

Main Results:

• A low percentage (6%) of transfected Vero cell clones exhibited stable HBsAg expression compared to murine cells (65%).
• HBsAg expression peaked at cell confluency and remained stable for months under specific culture conditions.
• The selected clone GAR 1412 was non-tumorigenic in nude mice and produced immunogenic 22 nm spherical HBsAg particles.

Conclusions:

• Stable HBsAg expression can be achieved in Vero cells, albeit with lower efficiency than in murine cells.
• The GAR 1412 clone represents a promising platform for producing immunogenic HBsAg for research and potential vaccine development.
• This system offers a stable and safe source of HBsAg for further immunological studies.