Britannica Sources used in this answer

How are genetically modified yeast cells used to make hepatitis B vaccine?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Rows of genetically modified barley plants grow in an outdoor test plot in Germany, with a yellow marker labeled 3 and protective netting overhead. — genetically modified organism Genetically modified crops are assessed for their impact on environmental factors such as soil quality.

Genetically modified yeast cells are used to produce the hepatitis B vaccine through recombinant DNA technology.1

In this process, researchers identify the specific genes of the hepatitis B virus that encode for the antigen—the surface protein that stimulates an immune response. This genetic material is inserted into the genome of yeast cells, such as Hansenula polymorpha, creating a genetically modified organism (GMO).231

These modified yeast cells act as biological factories; as they grow in fermentation media, they synthesize the viral surface protein. The resulting subunit vaccine is then purified from the yeast culture. Because the vaccine contains only these specific proteins and no live virus or infectious genetic material, it is a safe and effective way to confer immunity without the risk of causing the disease.32