Understanding HIV and Immune System Impact

The Human Immunodeficiency Virus (HIV) is a serious virus that attacks the body's immune system. The immune system is responsible for defending the body against infections and diseases. When HIV infects a person, it weakens this defense system, making the individual vulnerable to various illnesses that a healthy immune system would normally fight off easily. This advanced stage of HIV infection is known as Acquired Immunodeficiency Syndrome (AIDS).

How HIV Attacks the Immune System Cells

HIV specifically targets certain types of cells in the immune system. The main target of HIV is a type of white blood cell called a lymphocyte, specifically the CD4+ T lymphocyte (also known as CD4 cells or helper T cells). These cells are crucial commanders of the immune response. They help activate other immune cells, like B cells (which make antibodies) and cytotoxic T cells (which kill infected cells).

When HIV enters the body, it binds to and infects these CD4+ T cells. Inside the cells, the virus replicates, creating more copies of itself. Eventually, the infected CD4+ T cells are destroyed by the virus or by other parts of the immune system trying to clear the infection. As the number of CD4+ T cells declines, the immune system becomes progressively weaker, losing its ability to effectively respond to infections.

Analyzing the Options Provided

Let's look at the cells listed in the options and understand their roles in the body and whether they are primary targets of HIV:

Conclusion on HIV and Cell Destruction

Based on the understanding of how HIV works, the virus specifically targets and destroys lymphocytes, particularly the CD4+ T lymphocytes. This destruction is the primary reason for the weakening of the immunity in a person infected with HIV.

Therefore, the cells destroyed by the HIV virus, leading to a weakened immune system, are Lymphocytes.

Revision Table: Key Immune Cells and HIV

Additional Information on HIV and Immune System

• AIDS Defining Illnesses: When the CD4+ T cell count drops below a critical level (usually 200 cells per cubic millimeter of blood), the immune system is severely compromised. This makes the person susceptible to opportunistic infections and cancers that are rare in people with healthy immune systems. These are called AIDS-defining illnesses.
• Antiretroviral Therapy (ART): While HIV targets immune cells, modern treatments called Antiretroviral Therapy (ART) can effectively suppress the virus. ART prevents the virus from replicating and destroying CD4+ T cells, allowing the immune system to recover and preventing the progression to AIDS.
• Transmission: HIV is primarily transmitted through specific body fluids (blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids, breast milk) from an infected person to another. It is commonly spread through unprotected sex, sharing needles, or from mother to child during pregnancy, childbirth, or breastfeeding.