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How is genetically engineered yeast used to produce the hepatitis B vaccine?

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Vaccine development — genetic engineering The generation of vaccines relies heavily on techniques in genetic engineering.

The hepatitis B vaccine is produced using recombinant DNA technology, a process that allows researchers to isolate the genes of a pathogen that encode specific immunity-stimulating proteins, known as antigens.12

In this manufacturing process, the genetic material responsible for producing the hepatitis B surface antigen is inserted into yeast cells, such as Saccharomyces cerevisiae or Hansenula polymorpha. These genetically modified yeast cells act as biological factories; as they grow and ferment in a culture medium, they express and produce the viral surface protein.342

Once produced, the antigen is harvested and purified from the yeast cells to create a subunit vaccine. Because the final vaccine contains only the viral protein and not the live virus or its complete genetic material, it is incapable of causing infection while effectively stimulating the human immune system to produce protective antibodies.1