Which of the following is not a recombinant protein used in medical practice ?

Options

A. TPA ( tissue plasminogen activator)
B. Interferon ( α,β, and γ)
C. Vaccine (for hepatitis B)
D. Heparin

Answer

To determine which of the following is not a recombinant protein used in medical practice, we will analyze each option provided:

1. **TPA (Tissue Plasminogen Activator)**:
- TPA is a recombinant protein that is used in medical practice primarily for the treatment of blood clots. It works by dissolving clots that can block blood vessels, particularly in cases of heart attacks or strokes. Thus, TPA is a recombinant protein.

2. **Interferons**:
- Interferons are proteins that play a crucial role in the immune response. They are produced using recombinant DNA technology and are used in the treatment of various diseases, including certain types of cancer and viral infections. Therefore, Interferons are also recombinant proteins.

3. **Vaccines**:
- Many vaccines are developed using recombinant DNA technology, which allows for the production of specific antigens that can stimulate an immune response without causing disease. This makes vaccines a category of recombinant proteins used in medical practice.

4. **Heparin**:
- Heparin is an anticoagulant that is used to prevent blood clots. However, it is not produced through recombinant DNA technology. Instead, it is derived from animal sources, such as pig intestines or bovine lungs. Therefore, heparin is not a recombinant protein.

Based on this analysis, the answer to the question is that **Heparin** is not a recombinant protein used in medical practice.

### Final Answer:
**Heparin** is not a recombinant protein used in medical practice.