Hole forming-proteins called 'perforins' are produced by

Options

A. helper T cells
B. regularotry cells
C. cytotoxic T cells
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the production of hole-forming proteins known as 'perforins'. We need to identify which type of immune cell produces these proteins.

2. **Analyzing the Options**:
- **Option A: Helper T cells**: These cells play a crucial role in the immune response but do not produce perforins. Their primary function is to assist other immune cells.
- **Option B: Regulatory T cells**: These cells are involved in suppressing the immune response and do not produce perforins either.
- **Option C: Cytotoxic T cells**: These cells are known for their ability to kill infected or cancerous cells. They produce perforins, which are cytolytic proteins that create pores in the target cell membranes.
- **Option D: All of the above**: Since only cytotoxic T cells produce perforins, this option is incorrect.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Option C: Cytotoxic T cells**. These cells are responsible for producing perforins.

4. **Conclusion**: The hole-forming proteins called perforins are produced by cytotoxic T cells, which are essential for the immune system's ability to eliminate infected or malignant cells.

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