True statement about hepatitis B vaccine is

Options

A. Produced by recombinant DNA technology
B. Produced in E.coli
C. Formation of antibody polypeptide of pathogen
D. Whole pathogen is given

Answer

### Step-by-Step Solution:

1. **Understanding Hepatitis B and Its Vaccine**:
- Hepatitis B is a viral infection that affects the liver and is caused by the hepatitis B virus (HBV). It can be transmitted through sexual contact, contaminated needles, or from mother to child during childbirth.

2. **Vaccine Type**:
- The hepatitis B vaccine is classified as a subunit vaccine. This means that it contains only specific parts of the virus (subunits) rather than the whole virus.

3. **Production Method**:
- The vaccine is produced using recombinant DNA technology. This involves extracting the gene that codes for the hepatitis B surface antigen (HBsAg), which is a protein found on the surface of the hepatitis B virus.

4. **Use of Yeast in Production**:
- The extracted gene is inserted into a plasmid (a small circular DNA molecule) of a yeast cell, specifically Saccharomyces cerevisiae. This yeast is then cultured to produce the HBsAg protein.

5. **Immune Response**:
- Once the vaccine is administered, the body recognizes the HBsAg as a foreign substance and mounts an immune response. This includes the production of antibodies against the hepatitis B virus, providing immunity.

6. **Evaluating Statements**:
- The statements regarding the hepatitis B vaccine can be evaluated:
- **Produced by recombinant DNA technology**: True.
- **Produced in E. coli**: False, it is produced in Saccharomyces cerevisiae.
- **Formation of antibody polypeptide of pathogen**: False, the vaccine contains the gene for the antigen, not the antibodies themselves.
- **Whole pathogen is given**: False, only a subunit (the HBsAg) is provided.

7. **Conclusion**:
- The true statement about the hepatitis B vaccine is that it is produced by recombinant DNA technology.