The immune system fails to recognize self cells due to this reason

Options

A. production of lymphocytes which recognize foreign antigens
B. genetic defect in which antibodies are produced against self antigens
C. self cells have identical antigens
D. none of the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Immune System**: The immune system is designed to protect the body from pathogens (such as bacteria and viruses) by recognizing foreign antigens and producing antibodies against them.

2. **Self vs. Foreign Cells**: Normally, the immune system can distinguish between self-cells (the body's own cells) and foreign cells (invaders). Self-cells have specific antigens that are recognized by the immune system as "self".

3. **Autoimmunity**: In some cases, the immune system fails to recognize self-cells and mistakenly identifies them as foreign. This leads to the production of auto-antibodies that attack the body's own cells, resulting in autoimmune diseases.

4. **Causes of Autoimmunity**: The exact cause of why the immune system begins to attack self-cells is not fully understood. However, it is believed that genetic defects or mutations can lead to the production of antibodies against self-antigens.

5. **Examples of Autoimmune Diseases**: Conditions such as rheumatoid arthritis, multiple sclerosis, and lupus are examples of autoimmune diseases where the immune system attacks the body's own tissues.

6. **Conclusion**: Therefore, the immune system fails to recognize self-cells primarily due to genetic defects that lead to the production of antibodies against self-antigens.

**Final Answer**: The immune system fails to recognize self-cells due to genetic defects in which antibodies are produced against self-antigens.

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