Which one comes into action during organ transplants?

Options

A. T-cells
B. Phagocytes
C. B-cells
D. Stem cells

Answer

**Step-by-Step Solution:**

1. **Understanding Organ Transplants**: Organ transplants involve the transfer of organs (like kidneys, hearts, etc.) from one individual to another. These organs are made up of tissues, which in turn are composed of cells.

2. **Immune Response in Transplants**: When an organ is transplanted, the recipient's immune system may recognize the new organ as foreign tissue. This can lead to an immune response against the transplanted organ.

3. **Role of T Lymphocytes**: The immune response during organ transplants is primarily mediated by T lymphocytes (T cells). These cells are crucial in identifying and attacking foreign cells.

4. **Types of T Lymphocytes**: There are different types of T lymphocytes involved:
- **T Helper Cells**: Assist other immune cells.
- **T Killer Cells**: Directly attack and destroy infected or foreign cells.
- **T Memory Cells**: Provide long-term immunity by remembering past infections.
- **T Suppressor Cells**: Help regulate and suppress the immune response.

5. **Adaptive Immunity**: T lymphocytes are part of the adaptive (or acquired) immunity, which is specifically tailored to respond to pathogens and foreign tissues.

6. **Exclusion of Other Options**:
- **B Lymphocytes**: These are involved in humoral immunity (antibody-mediated immunity) and are not the primary players in organ transplant rejection.
- **Phagocytes**: While they play a role in the immune system, they are not directly involved in the rejection of transplanted organs.
- **Stem Cells**: These are not directly involved in the immune response during organ transplants.

7. **Conclusion**: The main cells that come into action during organ transplants are T lymphocytes (T cells).

**Final Answer**: T Lymphocytes (T cells) come into action during organ transplants.

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