Human hepatitis B vaccine from recombinant yeast.

Area of Science:

• Biotechnology
• Vaccinology
• Hepatology

Background:

• Hepatitis B virus (HBV) infection is a global health concern causing chronic liver disease, cirrhosis, and liver cancer.
• Current hepatitis B vaccines rely on HBsAg from infected human plasma, facing supply and safety limitations.
• Stringent purification is required to remove infectious agents from plasma-derived vaccines.

Purpose of the Study:

• To develop a safe and scalable hepatitis B vaccine using recombinant DNA technology.
• To express hepatitis B surface antigen (HBsAg) in yeast for vaccine production.
• To evaluate the immunogenicity and efficacy of the yeast-derived HBsAg vaccine.

Main Methods:

• Engineered yeast (Saccharomyces cerevisiae) to express HBsAg using recombinant DNA vectors.
• Purified HBsAg from recombinant yeast cell cultures.
• Formulated the purified antigen with alum for vaccination.
• Tested vaccine efficacy in animal models, including mice, grivet monkeys, and chimpanzees.

Main Results:

• Recombinant HBsAg produced in yeast elicited antibody production in vaccinated animals.
• Vaccinated chimpanzees demonstrated complete protection against homologous and heterologous HBV challenge.
• This marks the first successful recombinant cell-derived vaccine against a human viral infection.

Conclusions:

• Yeast-derived hepatitis B vaccine is immunogenic and protective.
• Recombinant technology offers a safe and scalable alternative to plasma-derived vaccines.
• This advancement has significant implications for global hepatitis B prevention efforts.