The discovery of the hepatitis B advanced beyond protecting people through blood transfusions from hepatitis B to the broader scope of protecting people from the disease. In the late 1960s, virologist Blumberg (Fox Chase Cancer Center (FCCC), Barbara Werner, immunologist, Manfred Bayer electron microscopist, and molecular biologist Lawrence Loeb, vigilantly described the small particles isolated from HBsAg-positive blood and visualized it through the electron microscope.They found out that some particles were whole viruses, others contained no nucleic acid that was the genes responsible for causing infection and the disease (Harford & Cabezon, 234-87).
It is from such assumptions that Hepatitis B virus (HBV) was identified as the causative agent of serum hepatitis. Blumberg first acknowledged this antigen as a serum protein explicit for aborigines in Australia. It was only later that the infectious nature of the antigen was identified, in which case it turned out to be the surface protein of HBV that is secreted into the bloodstream of infected patients in excess over viral particles.
After many centuries, the first licensed vaccines against HBV became accessible in the beginning of 1980s.The vaccine was produced by harvesting and purifying HBsAg from the serum of chronic carriers, given that there was no possibility for proliferation of the virus in vitro (Gleeson & Ortori, 45-76). Even though they were safe and effective, serum-derived vaccines were expensive and in relatively short supply because of shortage of human carrier plasma that met the requirements for the production of the vaccine. Since the 1980s, recombinant hepatitis B vaccines have been used as more practical alternatives with the HBsAg produced in yeast (Harford & Cabezon, 234-87).
HBV was established to be prevalent in many parts of the world, with more than two billion people having had contacted the virus, and more than 350 million people being chronic carriers of the virus.
Hepatitis B Vaccine Production Using Yeast. Yeasts have outstandingly been distinguished as capable of producing a potential vaccine against hepatitis B virus. This is a biological fact that has been founded on the rising track record of the expression platforms in the production of pharmaceuticals. Some of the commercially available, yeast-derived, recombinant pharmaceuticals are inclusive of insulin, the anti-coagulant hirudin, interferon-alpha-2a, and a variety of vaccines used against the hepatitis B virus and papillomavirus infections.
The yeast vaccines are particularly produced in either baker's yeast, known as Saccharomyces cerevisiae, the methylotrophic species Hansenula polymorpha and Pichia pastoris. For the case of this manuscript however, methylotrophs is considered in the production process for hepatitis B vaccines. The reason attached is that Methylotrophs yeast species produce a comparatively high balanced production of both the membrane and the protein component of a recombinant viral particle (Gleeson & Ortori, 45-76).
Among the most significant recombinant pharmaceuticals available were the yeast-derived vaccines that could be used against hepatitis B infections. The vaccines for Hepatitis B were derived from the particles containing hepatitis B surface antigen (HBsAg) inserted into host-derived membranes. The development of effective, yeast-derived recombinant hepatitis B surface proteins was hence the factor behind the success of current vaccination programs against hepatitis B.
In the most recent advancements, yeast-based HepB vaccines are being modified by including substitute adjuvant, in addition to RC-529, a non-toxic lipid, A mimetic35. Other developments incurred along include the coming of large surface antigen also called core protein sequences aimed at reducing the number of non-responders or developing a therapeutic vaccine. Several combination vaccines are also under development, including yeast-derived HepB particles